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376
METHODS FOR LIPID ANALYSIS An Annotated Bibliography
SPECIAL SCIENTIFIC REPORT-FISHERIES Na 376
EXPLANATORY NOTE
The series embodies results of investigations, usually of restricted scope, intended to aid or direct management or utilization practices and as guides for administrative or legislative action. It is issued in limited quantities for official use of Federal, State or cooperating agencies and in processed form for economy and to avoid delay in publication.
United States Department of the Interior, Stewart L. Udall, Secretary- Fish and Wildlife Service, Clarence F. Pautzke, Commissioner Bureau of Sport Fisheries and Wildlife, Daniel H. Janzen, Director
METHODS FOR LIPID ANALYSIS An Annotated Bibliography
By
Alvin L. Jensen-
Special Scientific Report- -Fisheries No. 376
1/ Experimental Zoology Branch, Physiology Division,
Directorate of Medical Research, U.S. Army Chemical Research and Development Laboratories, Army Chemical Center, Maryland, and Western Fish Nutrition Laboratory, U.S. Fish and Wildlife Service Bureau of Sport Fisheries and Wildlife Cook, Washington
Washington, D. C.
June 1961
METHODS FOR LIPID ANALYSIS
Since the early 1930's the field of lipid re- search has grown tremendously. In conjunction with the expansion of our knowledge of lipids, many methods for the determination of these constituents have been published at a pace which makes it difficult for the investigator to keep abreast of developments. This bibliography was compiled in order that references to the many methods might be brought together and made more readily available.
No effort has been made to include papers wherein the method of choice is "standard" or
only slightly modified, or those referred to in the "New Methods" section of the Journal of Lipid Research. Of the methods published before 1930, only the classical ones have been included. The papers are listed alphabetically by first author. Chemical Abstract numbers are included for the less common journals.
The author wishes to thank Dr. Charles G. Wilber and Mr. Paul F. Robinson of the Army Chemical Center for their many helpful sugges- tions .
Key to Symbols:
■^ Separation and purification
# Glycerides, fatty acids and total lipids
^ Phospholipids ■ Cholesterol
Abell, L. L., B. B. Levy, B. B. Brodie, and F. E. Kendall
1952. A simplified method for the esti- mation of total cholesterol in serum and demonstration of its specificity. Journal of Biological Chemistry, 195: 357-366. Serum is treated with alcoholic KOH to hydrolyze the cholesterol esters, the freed cholesterol is extracted into petro- leum ether, and an aliquot of the extract is used for determination of cholesterol by the Liebermann-Burchard color reac- tion.
It is shown by counter -current distri- bution that only about 2% of the material determined as cholesterol by this method is other material. The Schoenheimer- Sperry method produced the same results.
Abu-Nasr, A.M. and R. T. Holman
1954. Highly unsaturated fatty acids . III. Isolation of methyl eicosapen- taenoate, ethyl docosapentaenoate, "k and ethyl docosahexaenoate from
# cod liver oil esters by chromatogra-
phy. Journal of the American Oil Chemists Society, 31: 41-45.
Chemical Abstracts, 48:4229h (1954). Fatty acids from cod liver oil were separated on a Darco G-60 charcoal -Hyflo Supercel column using isopropanol as sol- vent and methyl behenate as displacer .
Abu-Nasr, A.M. and R. T. Holman
1955 . ' Isomerization of polyunsaturated fatty acids and their esters by sodium amide in liquid ammonia . Journal of
# the American Oil Chemists Society, 32: 414-418. Chemical Abstracts, 49:12857d(1955).
Polyenoic acids were isomerized by us- ing sodium amide in liquid ammonia, and determined by ultraviolet and infrared spec- trophotometry .
Ahrens, E. H., Jr. andL. C. Craig
1952. Separation of the higher fatty acids. ■^ Journal of Biological Chemistry, 195:
• 299-310.
Countercurrent distributioji was used to separate a synthetic mixture of lauric, myristic, palmitic, and stearic acids; a synthetic mixture of oleic, linoleic, and linolenic acids; and an unknown mixture of
t±ie fatty acids obtained by hydrolysis of pig mesenteric fat. Separations of saturated or unsaturated groups was good, but over- lapping occurred in mixtures containing both saturated and unsaturated acids.
Ahrens, E. H., Jr.
1955. Application of countercurrent dis- tribution for the study of lipids . _. Proceedings of the International Con-
ference on Biochemical Problems of Lipids, 2nd Ghent . A discussion of the applicability and use of counter-current distribution for lipid studies.
Albers, R. W. andO. H. Lowry
1955. Flourometric determination of 0. 1 to 10 micrograms of cholesterol. Ana-
■ lytical Chemistry, 27: 1829-1831.
The flourescence produced by cholester- ol in a trichloroethane, sulfuric acid, and acetic acid solution is used to measure the cholesterol extracted from 1 to 25 ug. of brain or other tissue. A stable, sensitive and precise method.
Allen, R. J. L.
1940. The estimation of phosphorus. Biochemical Journal, 34: 858-865. A modification of the Fiske-Subbarow reaction which uses amidol-sodium bisul- fite as reducing agent .
Anderson, D. M. W.
1959. Applications of infrared spectro- scopy: the identification and determi- nation of gas -chromatographic frac- tions. Analyst, 84: 50-55. Methods are described for collecting the components of mixtures separated by gas chromatography, and identification and quan- titative determination of the components by vapor-phase infra-red spectroscopy.
Appleton, H. D., B. N. Ladu, B. B. Levy, J. M. Steele, andB. B. Brodie
1953. A chemical method for the deter- mination of free choline in plasma. Journal of Biological Chemistry, 205: 803-813. The method involves extraction of
choline into acetone, evaporation of the acetone, and removal of interfering matter with butanol . After precipitation of choline as enneaiodide, the precipitate is dissolved in ethylene dichloride and measured spectro- photometrically at 365 mp.. As little as 5
jUg. of choline is estimated. The method ap- pears to be specific when used for plasma choline, but material other than choline is
also assayed when the method is used for urine or tissue analyses. Adsorbed iodine does not interfere.
Arcus, A. C.
1959. Nephelometric detection of lipides in chromatographic column effluents. Analytical Chemistry, 31: 1618-1620. A method is described for the rough esti- mation of the quantity of lipid material in ef- fluents from chromatographic columns. The lipid material is precipitated from a meth- anolic solution with water, and the suspension is measured by nephelometry. The method is not specific, and is only applicable to mate- rial soluble in MeOH and insoluble in MeOH-H,0 (1:2).
Armbruster, O. andU. Beiss
1957. Paper chromatography of the phos- . phatides. Naturwissenschaften, 44:
^ 420-421. Chemical Abstracts,
52:10268f (1958). A study of various paper-solvent com- binations with regard to their suitability for separation of phosphatides. Data concerning those combinations found to be acceptable are given.
Artom, C.
1941. Cephalins, choline -containing phos- pholipids, and total phospholipids in normal human plasma. Journal of Biological Chemistry, 139: 65-70. A comparison of methods of extraction and purification of lipids. The methods com- pared were:
1 . Extraction with cold alcohol followed by continuous hot alcohol extraction.
2. Precipitation with ammonium sulfate of the plasma proteins at pH 3, followed by continuous extraction with hot alcohol-
3 . Folch and Van Slyke method (Proceed-
*
ings of the Society of Experimental Bio- logy and Medicine,41: 514, 1939) of precip- itation with "colloidal iron" and magnesium sulfate.
The values that were obtained indicated that extraction of the phospholipids by all the above methods was probably complete, but washing procedures yield final products of slightly different compositions. The Folch and Van Slyke procedure was found to be reliable for routine analyses .
Artom, C.
1945. A quantitative method for ethanol- amine and serine as a basis for the de- termination of phosphatidyl ethanolamine A and phosphatidyl serine in tissues. Jour-
nal of Biological Chemistry, 157: 585- 594^ The method is based on the reaction of an ethanolamine -serine mixture with alkaline periodate before and after ethanolamine is removed by adsorption on Permutit. The NH., produced by the reaction is steam dis- tilled and determined. Conditions for use and limitations of the method are discussed.
Ashley, B. D. andU. Westphal
1955. Separation of small quantities of . saturated higher fatty acids by reversed-
^ phase paper chromatography. Archives
of Biochemistry and Biophysics, 56: 1-10. Fatty acids were separated on paraffin oil- er latex-coated paper with aqueous methanol saturated with cyclohexane or trimethylpen- tane, and aqueous methanol saturated with paraffin oil, respectively. Spots were detec- ted by spraying with bromothymol blue, or immersing in a solution of lead acetate and developing the spots as lead sulfide or rho- dlzonate. Separates 10-50/ig. of C.^-C^^ acids .
Awe, W . and B . Grote
1958. Paper chromatography of thiocyano- . gen derivatives of fatty acids. Fette,
J Seifen, Anstrichmittel, ^: 806-809.
* Chemical Abstracts, 53: 3737h (1959).
Fatty acid cyanogen derivatives are sepa- rated by paper chromatography using an acetic acid-undecane solvent system. The separated derivatives are located by spray-
ing the dried chromatogram with an FeNH4(S04)2 or FeCl3 solution in an ammo- nia atmosphere.
Axelrod, J., J. Relchenthal, andB. B. Brodie 1953. The direct determination of phos- phatidyl ethanolamine and phosphatidyl serine in plasma and red blood cells. Journal of Biological Chemistry, 204: 903-911. Ethanolamine and serine are determined by spectrophotometric measurement of their colored dinitroflourobenzene derivatives.
It was found that sensitivity of the Fiske and Subbarow phosphorus determination (Journal of Biological Chemistry, 66: 375, 1925) was increased 4-fold by heating 10 minutes in a boiling water bath after addition of reagents.
Ayers, C. W.
1956. Estimation of the higher fatty acids ^ Cy-CjQ. Analytlca Chlmica Acta 15:
• 77-83. ~ Methods are described for estimation of
the Cy-Cjg fatty acids as their copper or co- balt soaps. The soaps are dissolved in chlo- roform and the optical density of the solution is measured at 675 m/j. for copper or 525 m^. for cobalt.
Ballance, P. E. and W. M. Crombie
1958. Paper chromatography of saturated -^ and unsaturated fatty acids . Biochem-
# leal Journal, ^: 632-640.
Methods and solvent systems are describ- ed for reversed-phase chromatography of fatty acids on paper impregnated with paraf- fin oil, castor oil, or polythene. Data on the separation of over 40 fatty acids are given.
Bargeton, D., M. E. Trlcand-Redel, and P. Gros
1959. Comparison of results from three methods for the determination of serum cholesterol. Revue francaise d' etudes cllniques et biologiques, 4: 326-334. Chemical Abstracts, 53:18143e (1959).
A comparison of the Schoenheimer-Sperry (Journal of Biological Chemistry, 106: 145, 1934), Grigaut (Compte rendu hebdomadaire des seances et mgmoires de la Socigtg de biologie, 112:34, 1933), Machebouf and
Delsal (Bulletin de la Soci^t6 de chimie bio- logique, 24: 296, 1942), and Abell (Journal of Biological Chemistry, 195: 351, 1952) methods for cholesterol determination. The S-S and Abell methods were found to be superior to the other two methods with regard to the standard error inherent in the method.
Barron, E.J. and D. J. Hanahan
1958. Observations on the silicic acid chromatography of the neutral lipids
1 of rat liver, beef liver, and yeast.
Journal of Biological Chemistry, 231: 493-503. Pigm.ents and hydrocarbons were eluted from a column of silicic acid with hexane, sterol esters with 15% benzene in hexane, triglycerides and free fatty acids with 5% ether in hexane, free sterols with 15-20% ether in hexane, diglycerides with 30% ether in hexane, and monoglycerides with 90-100% ether in hexane.
Barry, G. T., Y. Sato, andL. C. Craig
1951. Distribution studies. XIII. Sep- . aration and estimation of the higher
^ normal fatty acids . Journal of Biologi-
* cal Chemistry, 188: 299-306.
C5 to C^g normal fatty acids were sepa- rated by counter -current distribution in isopropyl ether and 1 M potassium phosphate and estimated by titration .
Bartlett, G. R.
1959. Phosphorus assay in column chro- matography. Journal of Biological Chem-
^ istry, 234: 466-468.
A modified Fiske-Subbarow method which uses heating of the phosphorus reaction mix- ture in H2SO4 to produce an increase in light absorption at 830 mp.. This method permits greater latitude in reagent concen- trations. The color developed is stable for 24 hours .
Bauer, F. C, Jr. and E . F. Hirsch
1949. A new method for the colorimetric determination of the total esterified
# fatty acids in human sera. Archives of Biochemistry, 20: 242-250^
Fatty acid esters are converted to
hydroxamic acids and determined as col- ored ferric salts. A discussion of the pro- cedure and sources of error is included.
Beadle, G. W.
1944. An inositolless mutant strain of
neurospora and its use in bioassays .
Journal of Biological Chemistry, 156:
683-689. A method is described which is suitable for use with concentrations of inositol be- tween 5 and 30 itg.in 20 ml. of medium . A mutant strain of Neurospora crassa which requires inositol for growth is used in the bioassay.
Beattie, F. J. R.
1936. A colorimetric method for the de- termination of choline and acetyl- choline in small amounts. Biochemical Journal, 30: 1554-1559. Choline and acetylcholine are precipitated as their reineckates. The reineckate is dis- solved in acetone and measured colorimetri- cally.
Beerthuis, R. K., G. Dijkstra, J. G. Keppler, and J. H. Recourt
1959. Gas -liquid chromatographic anal- ysis of higher fatty acids and fatty- •h acid methyl esters. Annals of the New
# York Academy of Science, 72(art. 13):
616-632.
Fatty acids were separated by gas chro- matography and the separated acids at the exit of the column were combusted over CuO at 1000° and the evolved CO2 was meas- ured katharometrically.
Benham, G. H. and L. Klee
1950. An improved method for the de- termination of iodine numbers . Jour- nal of the American Oil Chemists Society, 27: 127-129. Chemical Ab- stracts, 44:5119c (1950). A modification of the method of Rosen- mund and Kuhnhenn (Ber . 56: 1262, 1923). The use of Hg acetate permits a determina- tion to be done in 1 minute.
Berenblum, I. andE. Chain A 1938. An improved method for the
colorimetric determination of phos- phate. Biochemical Journal, 32: 295- 298. Organic material is digested with HCIO4 and the phosphorus is converted to phospho- molybdate. The phosphomolybdate is ex- tracted into isobutyl alcohol, reduced with SnClo* and the color is read colorimetri- cally. The method is not subject to most of the interferences which affect the meth- ods of Fiske and Subbarow and Kuttner and Cohen. The standard method will deter- mine 1-lOO^g. of phosphorus, and the micro method 0.1-lOug.
Bergmann, W.
1940. The splitting of digitonides . ■ Journal of Biological Chemistry, 132:
471-472 . Digitonides are split with dry pyridine, the pyridine is distilled off, and the digit- onin is extracted with ether. The residue is steroid in yield of over
Bergstrbm, S. and K. Paabo.
1954. A method for the separation of _. saturated and monoun saturated fatty
^ acids through hydroxylation . Acta
chemica scandinavia, 8: 1486-1487. The fatty acids are hydroxylated with performic acid, methylated, and separated by elution from a silicic acid column.
Berk, L. C, N. Kretchmer, R. T. Holman, and G. O. Burr 1950. Microdetermination of uns'atu- rated fatty acids by alkali isomeriza- * tion. Analytical Chemistry, 22:718-
720. Aqueous alkali and high temperature and pressure are used for isomerization of un- saturated fatty acids . The fatty acids are then determined by ultraviolet spectro- photometry. A discussion of the method and data for linoleic, linolenic, and arachidonic acids are presented.
Bertram^ S. H. and R. Rutgers
1938. The estimation of glycerol and
and some other hydroxylated compounds . Recueil des travaux chimiques des Pays -Bas et de la Belgique, 57: 681-687.
Chemical Abstracts, 32:78575(1938). The copper complex formed with glyc - erol in alkaline solution is acidified, KI is added, and the excess is titrated with thio- sulfate .
Best, M., E.J. VanLoon, J. D. Wathem, and A.J. Seger 1954. Comparison of serum cholesterol methods. American Journal of Medi- ■ cine, 16: 601.
Serum cholesterol was determined by the methods of Schoenheimer-Sperry (Jour- nal of Biological Chemistry, 106: 745, 1934); Abell, et al (Journal of Biological Chemistry, 195: 357, 1952); Gershberg-Forbes (Jour- nal of Laboratory and Clinical Medicine, 27: 1439, 1942); modified Pearson, et al (Analyt- ical Chemistry, 25: 813, 1953); and Zlatkis, Zak, and Boyle (Journal of Laboratory and Clinical Medicine, 41: 486, 1953). The Abell, et al, and Schoenheimer-Sperry methods agreed closely. When compared to the Abell method, the values of the Gershberg-Forbes, Pearson, and Zlatkis methods were higher by 15, 35, and 90 mg. percent, respective- ly. Since an alcohol -acetone extract of se- rum yields similar results by the Schoen- heimer-Sperry and^Zlatkis methods while the Zlatkis method yields values of 90 mg. percent higher when used directly on the same serum, it is suggested that the Zlatkis method measures a non-extractable lipid of protein as well as cholesterol.
Bevan, T. H., G.I. Gregory, T. Malkin, and A. G. Poole 1951. Chromatographic separation of . choline -containing phospholipids from
. phospholipid mixtures. Journal of the
Chemical Society, 841-842. Phospholipids were separated by chroma- tography on cellulose columns or on paper using a chloroform, water, and ethanol mix- ture as solvent. Ethanolamine- and serine- containing phospholipids were located on the developed chromatogram with ninhydrin, and choline -containing phospholipids were located with phosphomolybdic acid- stannous chloride reagent. Choline phospholipids were obtain- ed uncontaminated.
Beveridge, J. M. R. andS. E. Johnson
1949. The determination of phospho- lipid phosphorus. Canadian Journal
^ of Research, 27E: 159-163.
Phospholipid is digested with H2SO4 and color is developed with molybdate -hydra- zine sulfate reagent (Boltz and Mellon, In- dustrial and Engineering Chemistry, Analyt- ical Edition, 19: 873, 1947) and read at 830 mu . Accuracy of the method is within 1% on a 20 ug. sample of phosphorus.
Black, S.
1949. A microanalytical method for the volatile fatty acids . Archives of Bio-
• chemistry, 23: 347-359.
The volatile fatty acids are determined by microdiffusion from an acidified solu- tion into an alkaline solution, and micro- titration of the excess alkali. Range: 0.2-2.0 "equivalents; error: <0.03uequiv- alent .
Blankenhom, D. H. andE. H. Ahrens, Jr.
1955. Extraction, isolation, and identi- 1 fication of hydrolytic products of tri-
^ glyceride digestion ui man. Journal
of Biological Chemistry, 212: 69-81. A description of methods for extraction of lipids from intestinal contents and sepa- ration into fatty acid, bile acid, and mono-, di-, and triglyceride fractions.
BU^, E. G. and W. J. Dyer
1959. A rapid method of total lipid ex- . traction and purification . Canadian
_ Journal of Biochemistry and Physiology,
• 37: 911-917.
A simplification of the method of Folch, et al, (Journal of Biological Chemistry, 191: 833, 1951). Lipids are extracted by homo- genization of tissue with CHCl3-MeOH in such proportions that a miscible system is formed with the water in the tissue. The homogenate is separated into a chloroform layer containing the lipids and a methanoUc layer containing the non-lipid material by addition of chloroform and water . Extrac - tion of the lipids is essentially complete.
Bloor, W. R.
1916. The determination of cholesterol in blood. Journal of Biological Chem- " istry, 24: 227-231."
Blood is extracted with alcohol -ether (3: 1), the extract is evaporated to dryness and the residue is extracted with chloro- form. Cholesterol is then determined colorimetrically using the Liebermann-Bur- chard color reaction.
Bloor, W. R.
1928. The determination of small amounts ^ of lipid in blood plasma . Journal of
Biological Chemistry, 77: 53-73. Nicloux reagent (Ag2Cr207 in H2SO4) is used for oxidation of the extracted lipid, and the excess dichromate is titrated with thio sulfate.
Bloor, W. R.
1929. The oxidative determination of phospholipid (lecithin and cephalin)
A in blood and tissues. Journal of Bio-
logical Chemistry, 82: 273-286. The phospholipids are separated by pre- cipitation with acetone -MgCl2 and determin- ed by oxidation with Nicloux reagent and titration of excess dichromate with thiosul- fate.
Bloor, W. R.
1947. A colorimetric procedure for de- _ termination of fatty acids . Journal of
Biological Chemistry, 170: 671-674. Fatty acids are determined-by colorimet- ric measurement of the color change pro- duced by oxidation with Nicloux reagent. A special colorimeter Is required.
Bohm, P., S. Dauber, andL. Baumelster
1954. Neuraminic acid, its occurrence and its determination in serum . Klin- ische Wochenschrift, ^: 289-292. Chemical Abstracts, 48:7674e (1954). Serum protein is precipitated with tri- chloracetic acid, centrifuged, and washed with water. The precipitate is treated with Bial reagent and heated, and the red-violet reaction product of neuraminic acid is ex- tracted with amyl alcohol and read at 570 mu.
Bohm, P. andG. Richarz
1954. Determination of inositol in phos- phatides. Zeitschrift fiir physiolog- A ische Chemie, 298: 110-120. Chi^-
ical Abstracts, 49:4462d (1955). Lipid material is hydrolyzed with HCl and the hydrolysate is chromatographed on paper. The separated inositol is extracted with water, oxidized with periodate, and measured iodometrically,
Boldingh, J.
1950. Fatty acid analysis by partition chromatography. Recueil des travaux ■^ chimiques des Pays-Bas et de la Belgi-
• que, 69: 247-261 (in English). Chem- ical Abstracts, 44:6348h (1950).
A method is described for separation of C5-C18 saturated n-fatty acids from their mixtures and hydroxy fatty acids from satu- rated n-fatty acids by chromatography on a rubber column.
Boldingh, J.
1953 . Separation of fatty acids by chro- matography. Koninkl. Vlaam. Acad. Wetenschap . , Letter . en Schone » Kunsten Belg., Kl. Wetenschap.,
^ Intern. CoUoquim Biochem . Problem
Lipiden, Brussels, p. 64-81 (in Eng- lish). Chemical Abstracts, 49:2097h (1955). Fatty acids were separated on a column of rubber powder swollen with peanut oil,, with acetone -water -peanut oil as mobile phase .
Borgstrom, B.
1952. Investigation on lipid separation ■ic methods. Separation of phospholipids
# from neutral fat and fatty acids . Acta ^ physiologica Scandlnavica, 25: 101-110.
Acetone-MgCl2 precipitation gives good separation of phospholipids, with about 1% of the phospholipids dissolving in the solu- tion. MgO chromatography gives phospho- Upid-free neutral fat, but poorer purity of phospholipid, and cannot separate free fatty acids from choline -containing phospho- lipids. Non -choline -containing phospho- lipids are not recoverable unchanged. Silic- ic acid chromatography is slower than
acetone -MgCl2 precipitation, but gives best all-around results; neutral fat and free fatty acids are eluted quantitatively with CHCI3, and phospholipids with MeOH.
Borgstrom, B.
1952. Investigation of lipid separation . methods. Separation of cholesterol
^ esters, glycerides, and free fatty acids .
_ Acta physiologica Scandlnavica, 25:
111-119. ~
Silicic acid chromatography is used for separation of cholesterol esters from glyc- erides and free fatty acids. Free fatty acids are separated from glycerides in ab- sence of lower glycerides by extraction of the acids from a petroleum ether solution with alkaline 50% ethanol . In the presence of lower glycerides which would be extract- ed into the alcoholic solution, IRA -400 ion exchanger is used to separate the free fatty acids from the glycerides .
Borgstrom, B.
1954. Investigation on lipid separation . methods. III. Separation of tri-, di-,
_ 1-mono-, and 2-monoglycerides. Acta
physiologica Scandlnavica, 30: 231-239. In the method described, tri-, di-, and monoglycerides are separated from their mixtures by chromatography on silicic acid (2-monoglycerides are partially isomerized). 1-mono- and 2-monoglycerides are separa- ted from tri- and diglycerides by partition chromatography with heptane and 80% aque- ous ethanol as phases. After oxidation of 1 -monoglycerides with periodic acid, the 2-monoglycerides can be isolated by chro- matography on silicic acid.
Boyd, E. M.
1931. Low phospholipid values in dog plasma . Journal of Biological Chem- istry, 91: 1-12. A modification of Bloor's oxidation meth- od (Journal of Biological Chemistry, 82: 273, 1929) for use in determination of low phos- pholipid levels. Essentially the same phos- pholipid values were obtained with or with- out heat in the alcohol -ether extraction of plasma. Substitution of ethyl ether for pe- troleum ether in extraction of the alcohol-
ether residue gave more consistent and slightly higher phospholipid values .
Boyd, E. M.
1933 . A differential lipid analysis of ^ blood plasma in normal young women
by microoxidative methods . Journal " of Biological Chemistry, 101: 323-336.
The oxidative procedure is recommended for determination of various lipids in the same extract as it eliminates the possibil- ity of summation of errors by using differ- ent methods.
Bloor's method (Journal of Biological Chemistry, 77: 53, 1928) is used to deter- mine total fatty acids after saponification of the lipids (99% recovery of known solu- tions and reproducibility of + 2%), and mod- ifications of Yasuda's method (Journal of Biological Chemistry, 92: 303, 1931) for oxidation of cholesterol digitonide (stock determinations reproducible + 2%). Con- firms observations that 1/2 hour heating is necessary for complete oxidation. Boyd's modifications (Journal of Biological Chemistry, 91_: 1, 1931) of Bloor's method are used for phospholipid determination. Free cholesterol is estimated after remov- al of phospholipid. The method checks within experimental error with values from direct precipitation from alcohol-ether ex- tract (96% recovery with + 4.5% agreement on duplicates).
Boyd found difficulty in Okey's method (Journal of Biological Chemistry, 88: 36 7^ 1930) for oxidative determination of choles- terol as the digitonide with respect to repro- ducibility and accuracy. Phospholipids are saponified with NaOH before determination of iodine numbers of phospholipid fatty acids, as direct determinations on whole phospho- lipid according to Yasuda (Journal of Biolog- ical Chemistry, 94: 401, 1931-2) gave erra- tic and variable results .
Boyd, E. M.
1936. The extraction of blood lipids. » Journal of Biological Chemistry, 114:
223-234. Effects of variables on extraction of blood lipids with Bloor's extract (alcohol - ether, 3:1) were studied.
It was found that when the extracts of blood are sufficiently diluted (at least 20: 1) extraction is complete.
Boyd, E. M.
1936. The extraction of lipids from the -^ red blood cells . Journal of Biological A Chemistry, 115: 37-45.
The effects of variables on extraction of blood cell lipids were studied and are dis- cussed.
Incompletely dried acetone used in MgCl2 precipitation gave low phospholipid values .
Boyd, E. M.
1937. The storage of lipid extracts. Journal of Biological Chemistry, 121: 485-496.
A decrease of phospholipid during 1-3 months of storage was observed. After 3-6 months of storage a decrease in cholesterol esters, total cholesterol, and total lipid, in- crease in "neutral fat" and free cholesterol, and no appreciable change in total fatty acids was observed. Changes were generally un- affected by storage conditions of light, tem- perature (refrigerator or room), or solvent (EtOH or EtOH-Petr. ether). See also: Halliday Oournal of Nutrition, 16:285, 1938).
Boyd, E. M.
1937. The oxidative micro-estimation of ^ plasma total lipid. Journal of Labora- * tory and Clinical Medicine, 22: 956-959.
The factor of 3.25 is proposed in place of the factor of 3.7 used by Bloor for conver- sion to total lipid value of the total fatty acid- total cholesterol titration with potassium di- chromate.
Boyd, E . M ,
1938. The oxidative micro -estimation of blood lipids. American Journal of Clin-
9 ical Pathology. Technical Supplement,
2: 77-90. Lipids are extracted with alcohol-ether (3:1), oxidized with Nicloux reagent and K2Cr207, and unreacted dichromate is ti- trated.
Boyd, G. S.
■^ 1954. The estimation of serum lipopro-
teins. A micromethod based on zone electrophoresis and cholesterol esti- mation. Biochemical Journal, 58: 680- 685. A method is described for the separation of serum lipoproteins by paper electro- phoresis. Protein was located by staining with bromophenol blue. Cholesterol was extracted with acetone -ethanol (1: 1) and estimated by the Liebermann-Burchard re- action .
Boyd, M. J. andM. A. Logan
1942. Colorimetric determination of serine. Journal of Biological Chem- istry, 146: 279-287. The formaldehyde formed by the action of periodate on serine is quantitatively distill- ed from the reaction mixture, condensed with 1, 8-dihydroxynaphthalene-3, 6-disul- fonic acid, and measured colorimetrically. Required 1-5 mg. serine. Error 1-2%.
Bradbury, R. G.
1951. Mic redetermination of glycerol. Mikrochemie (vereinigt mit Mikro- • chemica Acta), 38: 114-119. Chemi-
cal Abstracts, 45:6857c (1951). Glycerol is freed from the fat by hydro - lyzing with KOH and converted to isopropyl- iodide by reaction with HI in the presence of propionic acid. TTie I2 freed during the reaction is collected in a solution of Br and sodium acetate in acetic acid, which oxi- dizes the I to IO3-. Excess Br is removed from the solution and I is freed and titrated with Na2S203 .
Bragdon, J. H.
1951. Colorimetric determination of
^ blood Lipides. Journal of Biological
Chemistry, 190: 513-517. A modification of Bloor's dichromate oxidation method (Journal of Biological Chemistry, 170: 671, 1947). K2Cr207 in H2 SO4 is used in place of Ag2Cr207, as Ag may contain CI which would interfere with, colorimetric measurements. Better oxidation is obtained, as well as a straight - line curve of optical density.
Bragdon, J. H.
1956. Lipid nomenclature (recommenda- tions regarding the reporting of serum lipids and lipoproteins). American so- ciety for the study of arteriosclerosis. Circulation Research, 4: 129. The following are recommended:
1. The factor 1.67 be used to convert weight of cholesterol present in esterified form into weight of cholesterol ester. (Kel- sey and Longenecker, Journal of Biological Chemistry, 139: 727, 1949).
2 . The ratio of free cholesterol to total cholesterol be expressed as a decimal.
3 . The factor 25 be used to convert lipid phosphorus to phospholipid.
4. The amount of phosphorus in a Bloor extract be considered the correct lipid phosphorus content of serum . (Van Slyke,. Journal of Biological Chemistry, 200: 525, 1953).
5. Relative amounts of cholesterol and phospholipid be expressed as the ratio of total cholesterol to phospholipid, as a deci- mal . Values used should represent weights, not moles.
6. Triglycerides and fatty acids be re- ported as triglycerides, which predominate. The term "neutral fat" be avoided or spe- cifically defined. Triglycerides be report- ed in milligrams. The term millequivalents be confined to values for fatty acids deter- mined by titration when additional determi- nations are not available for the calculation of triglycerides.
Brand, F . C . and W . M . Sperry
1941. The determination of cerebro- sides. Journal of Biological Chemis- try, 141: 545-553. A modification of the Miller and Van Slyke (Journal of Biological Chemistry, 114: 583, 1936) method for sugar determination. The cerebrosides are hydrolyzed, the freed sug- ars are oxidized with ferricyanide,. and the ferrocyanide formed is titrated with eerie sulfate .
Brante, G.
• 1949. Studies on lipids in the nervous A system with special reference to quan-
■ titative chemical determination. Acta
physiologlca Scandinavica, 18 (suppl .
63): 1-189. Metiiods are described for the determina- tion of total lipids (gravimetric), phospho- lipids (modified Fiske-Subbarow), choline, ethanolamine, amino nitrogen, glycerol, hexose, inositol, and cholesterol.
Breusch, F. L. and E. Ulusoy
1946. Isolation and identification of fatty ^ acids as bis-(p-dimethylaminophenyl)-
J ureides. Archives of Biochemistry, 11:
• 489-498.
Free fatty acids are isolated from fat mix- tures in approximately 80% yield by precipi- tation as ureides from ether solution with bis-(p-dimethylaminophenyl)-urea . The properties, melting points, and solubilities of the ureides of various fatty acids are given.
Brown, F .
1950. Separation of the lower fatty acids ^ as anions by paper chromatography.
# Biochemical Journal, 47: 598-600. The lower fatty acids were separated by
paper chromatography as their Na salts us- ing n-butanol as developer in the presence of ammonia. The spots are revealed by spraying with a solution of bromothymol blue .
Brown, H. H., A. Zlatkis, B. Zak, and A. J. Boyle
1954. Rapid procedure for determination _ of free serum cholesterol. Analytical
Chemistry, 26: 397-399. AICI3 or A1(0H)3 is used to gather digiton- ide precipitate and the color produced with the ferric chloride reagent of Zlatkis, Zak, and Boyle (Journal of Laboratory and Clini- cal Medicine, 41: 486, 1953) is measured colorimetrically .
Brown, M., D. A. Yeadon, L. A. Goldblatt, and J. W. Dieckert
1957. Chromatography of phospholipids and related compounds on glass paper impregnated with silicic acid. Analyt- ical Chemistry, 29: 30-31. A method for the separation and identi- fication of phospholipids and some of their cleavage products is described. A phenol.
•
ethyl ether, acetone, and water solution is used to develop the chromatogram on a silicic acid-impregnated glass paper. Char- ring with sulfuric acid is- used to locate spots on the paper. (Ethanolamine and cho- line chloride are not detectable by this tech- nique.) A modified Dragendorf reagent (Bregoff, et al. Journal of Biological Chem- istry, 205: 565, 1953) or phosphomolybdic acid reagent (Levine and Chargaff, Journal of Biological Chemistry, 192: 465, 1952) is used for identification of quaternary ammo- nium compounds, and Ninhydrin reagent for detection of primary amino compounds .
Briickner, J. 1941.
Estimation of cerebrosides . Zeit-
schrift fijr physiologische Chemie, 268: 163-170. Chemical Abstract^ 35:7436^ (1941). ~
Cerebrosides are hydrolyzed with H2SO4, the fatty acids are removed with CHCI3, and galactose is determined using the orcin rea- gent. Cerebrosides are calculated from the amount of galactose.
Buchanan, M. A.
1959. Paper chromatography of the satu-
■^ rated fatty acids . Analytical Chemistry,
• 31: 1616-1618.
A method is described for chromatography of fatty acids on paper treated with mineral oil. The chromatogram is developed at 37'C with acetic acid - 88% formic acid - 30% hydrogen peroxide (6: 1: 1) for separation of the even-numbered straigjit-chain saturated fatty acids from lauric to lignoceric acid in the presence of large amounts of unsaturated acids. Mercuric acetate and s-diphenylcar- bazide were used for locating spots on the chromatogram .
BuUiard, H., I. Grundland, andM. Maillet 1950. Histochemical detection of cell phosphatides. Compte rendu hebdoma- daire des seances et memoires de la ^ Societg de biologie, 144: 192-194.
Chemical Abstracts, 44:100241(1950). Phosphatides were detected in tissue sec- tions by soaking the formalin -fixed tissue in CdCl2> washing in acetone, and convert- ing the Cd which had combined with the leci-
10
thin into CdS by exposure to H2S .
Burmaster, C. F.
1946. Microdetermination of OtandQ glycerophosphates. Journal of Biolog- ical Chemistry, 164: 233-240. Results of colorimetric measurement of the orthophosphate produced by the reac- tion of periodate on a glycerophosphate fol- lowed by acid hydrolysis agree with those obtained by titration of the reduced period- ate. Microcolorimetric methods suitable for the analysis of sodium glycerophosphate and phosphorus compounds in phospholipid hydrolysates, for inorganic phosphorus, cx phosphorus, (cX + "S" ) phosphorus, and to- tal phosphorus are described.
ing the developed chromatogram with nin- hydrin .
Cahn, T., J. Houget, and R. Agid
1948. The determination of glycerophos- phoric acid. Application to the case of the phosphatides . Bulletin. Societe chimique de France, pp 666-668. Chemical Abstracts, 42: 8860d(1948). Phosphatides are saponified, unsaponifi- ables are removed, the solution is acidi- fied, the fatty acid is removed, glycero- phosphoric acid is precipitated as the Ba salt, and P is determined. Unsaponifiable matter, fatty acids, and glycerophosphoric acid may all be determined on a 0.5 to 1.0 g. sample by this method.
Burmaster, C. F.
1946. The microdetermination of serine and ethanolamine in phospholipide hydro - A lysates. Journal of Biological Chemis -
try, 165: 1-6.
Ethanolamine and serine are determined by microdiffusion of the ammonia produced by periodate in a solution nearly saturated with potassium metaborate. Cephalin nitro- gen can be measured by this method in the presence of all the known components of phospholipid acid hydrolysates . It is a more specific measure of cephalin than the HNO2 method of Van Slyke (Journal of Biological Chemistry, 16:121, 1913-14). No indication was found of the reaction of hydroxylamine with periodate to form NH3 which Nicolet (Journal of the American Chemical Society, 6J.: 1615, 1939; Journal of Biological Chem- istry, 139: 687, 1941) described.
Obtained a better yield than Ramsey (Bio- chemical Journal, 35: 39, 1941), since Ram- sey's addition of K2CO3 to acid solution causes generation of heat and evolution of CO2 and some destruction of NH3 by the hot acid periodate .
Burness, A. T. H. andH. K. King
1958 . Detection of fatty acids on paper ^ chromatograms by means of ninhydrin.
Biochemical Journal, 68: 32P. Ethylamine or ammonia is used in the developing solvent, and the salts formed with the fatty acids are detected by spray-
Candela, A., P. Capella, andG. Jacini 1956. Researches on phosphatidic acids. III. Olii miner ali, grassi e A saponi, colori e vernici, 33: 99-101.
Chemical Abstracts, 50:16887g (1956). Choline, in 65 . 5% yield, was obtained by treatment of egg lecithin with carrot enzymes and a buffer, acidification of the solution with HCl, and extraction with Et20.
Cannon, J. A., K. T. Zilch, andH. J. Dutton 1952. Countercurrent distribution of
if methyl esters of higher fatty acids.
• Analytical Chemistry, 24: 1530-1532.
The methyl esters of the higher fatty acids were separated by countercurrent distribution in a pentane -hexane vs nitroethane-nitromethane solvent system. Applicability of the method is discussed.
Carayon-Gentil, A., andE. Corteglana
1942. Phosphoaminolipides of brain tis- sue. Fractionation and estimation of i choline -containing substances. Bulletin
de la Societe de chimie biologique, 24: 89-96. Chemical Abstracts, 38:6312^ (1944). Free choline, lecithin and cephalin, and sphingomyelin are obtained from brain tis- sue by selective extraction with Me2C0, pe- troleum ether, and MeOH-CHCl3 (3:1), re- spectively. The extracts are hydrolyzed with boiling alcoholic HCl and choline is es- timated by acetylation and estimation by
11
*
action on leech muscle of the acetylcho- line formed.
Cardini, C. E. andM. E. Serantes
1943. Methods of extracting sphingo- myelin. Anales de farmacia y bio- quimica. Buenos Aires, 14: 123-132. Chemical Abstracts, 38:4'6307 (1944). Initial extraction of material by Bloor's method (Tournal of Biological Chemistry, 82: 273, 1929), followed by reextraction of the tissue by the method of Thannhauser (Jour- nal of Biological Chemistry, 129: 709, 1939) is recommended.
Carlson, L. A. and L. B. Wadstrom
1958. A colorimetric method of deter- mining unesterified fatty acids in
^ plasma . Scandinavian Journal of Clin-
ical and Laboratory Investigation, 10: 407-414. ~
The lipids are extracted with chloroform - methanol (2: 1) . Phospholipids are separated on silicic acid, and fatty acids on Amberlite IRA-400 resin. The methylated fatty acids are determined colorimetrically as the hy- droxyamic acids. Two milliliters of plasma may be used for determination of unesteri- fied fatty acids, glycerides, phospholipids, and cholesterol. The method is sensitive to amounts of fatty acid from 0.5 to 4.0 ^equivalents. With 2 . 0 ^ equivalent, re- covery was 97.6% and error + 2.5%.
Carlson, L . A . and L . B . Wadstr'dm
1959. Determination of glycerides in ♦ blood serum . Clinica Chimica Acta,
4: 197-205. Glycerides are separated from phospho- lipids by silicic acid chromatography and saponified. The glycerol is then determin- ed by periodic acid oxidation and estimation of the formaldehyde formed.
Carpenter, K. J., A. Gostis, and D. M. Heg- sted
1957. Estimation of total cholesterol in serum by a micro method. Clinical Chemistry, 3: 233-238. An adaptation of the method of Albers and Lowry (Analytical Chemistry. 27: 1829, 1955) for use in determination of blood serum
cholesterol. H2SO4 is added to a
1, 1, 2-trichloroethane-acetic anhydride solution of cholesterol, and the floures- cence which develops is measured .
Cavanaugh, D. J. and D. Click
1952. Determination of cholesterol in microgram quantities of tissue . Ana- lytical Chemistry, 24: 1839- 1841 ] A microadaptation of the Sperry-Webb method (Journal of Biological Chemistry, 187: 97, 1950), for use in analysis of cholester- ol in microtome sections of tissue. Error of the method ranges from 1.5 to 4.5% de- pending on sample size .
Chapman, R. A. andK. MacKay
1949. The estimation of peroxides in fats and oils by the ferric thiocyanate ^ method. Journal of the American Oil
Chemists Society, 26: 360-363. Chem- ical Abstracts, 43:68"40h (1950). It was found, in agreement with the find- ings of Lea (Journal of the Society of Chem- ical Industry, 64: 106, 1945), that atmos- pheric oxygen interferes with the determina- tion of peroxide by the ferric thiocyanate method. Exclusion of air and use of nitro- gen atmosphere markedly reduced the per- oxide values determined by the ferric thio- cyanate method.
Charlampous, F. C. and P. Abrahams
1957. Biochemical studies on inositol. I. Isolation of myo- inositol from yeast and its quantitative enzymatic estima- tion. Journal of Biological Chemistry, 225: 575-583. Methods for the extraction, purification, and crystallization of myo -inositol from yeast cells are described. A method is described for the colorimetric estima- tion of inositol using the reduction of
2, 6-dichlorophenolindophenol by inositol dehydrogenase in the presence of inositol.
Chargaff, E. 1 1942. A study of Lipoproteins . Journal * of Biological Chemistry, 142: 291-504.
Ether extraction and dialysis were used to remove "lipovitellin" from egg yolk, and from it removed the phosphopha tides.
12
•
▲
Ethanolamine and choline in the phospha- tide fraction were separated as ethanol- amine 3, 5-diiodosalicylate and choline chloride -6 HgCl2 double salt.
Chargaff, E., C. Levine, andC. Green
1948. Technique for the demonstration by chromatography of nitrogenous lipide constituents, sulfur-containing amino acids, and reducing sugars. Journal of Biological Chemistry, 175: 67-71. HCl hydrolysis and paper chromatography were used to separate components. Tested for choline with phosphomolybdic acid, ethan- olamine and serine with ninhydrin, and re- ducing sugars with m-phenylenediamine di- hydrochloride .
Chen, P. S., Jr., T. Y. Toribara, and H. Warner
1956. Micro determination of phosphor- us. Analytical Chemistry, 28: 1756- 1758. A modification of the method of Ammon and Hinsberg (Zeitschrift fiir physiolog- ische Chemie, 239: 207, 1936) for use in determining as little as 0 . 15 ng . of phos - phorus in blood and urine. Ascorbic acid is used to reduce phosphomolybdate . Ef- fects of variables are given. Results are identical with Fiske-Subbarow method. The method is suitable for lipid phosphor- us determination.
Chiamori, N. and R.J. Henry
1959. Study of the ferric chloride meth- od for determination of total cholester- ol and cholesterol esters. American Journal of Clinical Pathology, 31: 305- 309. ~
FeCl3 -acetic acid reagent is used to pre- cipitate serum proteins, and the cholesterol color is developed with H2SO4. Bromine in- terference can be avoided by removing it with an ion -exchange resin.
Traces of digitonide interfered with the determination of cholesterol by the method of Pearson (Analytical Chemistry, 25: 813, 1953), using p-toluenesulfonic acid. Excess silver iodate will interfere with the color reaction (Rice and Lukasiewicz, Clinical
Chemistry, 3: 160, 1957).
Christl, H.
1953. Determination of acetal phospha- tide in tissues. Zeitschrift fiir physio - ▲ logische Chemie, 293: 83-88. Chem-
ical Abstracts, 49: 13346d (1955). A modification of the method of Feulgen (Zeitschrift fiir physiologische Chemie, 287: 90, 1951) for use in the determination of tissue acetal phosphatides.
Clayton, M. M., P. A. Adams, G. B. Mahoney, S. W. Randall, and E. T. Schwartz
1959. Micro methods for the determina- _ tion of chylomicron counts, fatty esters,
lipid phosphorus, and cholesterol in blood serum . Clinical Chemistry, 5: 426-444. Procedures for determination of lipid components on 75yul . samples of blood serum are given. After alcohol -ether ex- traction, the fatty esters are determined by colorimetric measurement of the ferric hydroxamate complex color developed with acidified ferric perchlorate (Hill, Industri- al and Engineering Chemistry, Analytical Edition, 18: 317, 1946, Ibid. 19: 932, 1947, and Bauer and Hirsch, Archives of Biochem- istry, 20: 242, 1949).
Phospholipids are oxidized with H2SO4 and H2O2 and determined by the Fiske- Subbarow colorimetric method. Cholester- ol esters are hydrolyzed with benzyltri- methylammonium hydroxide and total cho- lesterol is determined by color development with H2S04-acetic anhydride.
Cole, P. G., G. H. Lathe, and C . R. J. Ruthven 1953. The application of counter -current methods to the fractionation of lipid ma- terial from brain. Biochemical Journal, 54: 449-457. A water-methanol-carbon tetrachloride solvent system is described for use in coun- ter-current fractionation of brain lipids, and the behavior of the lecithin, cephalin, and sphingomyelin-cerebroside fractions is de- scribed. Variations of the solvent system and its uses are discussed.
•
13
Coleman, CM. and G. Middlebrook
1957. Interface enrichment of methylene ^ blue by fatty acids with micro -analytic
applications. Science, 126: 163. A heptane solution of fatty acids is enrich- ed by methylene blue when in contact with an aqueous solution of the dye. Spectrophoto- metric measurement of the enriched heptane solution is used for determination of the a- mount of fatty acids present.
Collins, F. D. andL. W. Wheeldon
1958. Studies on phospholipids. 4. De- termination of ethanolamine and se- rine. Biochemical Journal, 70: 46-49.
After extraction and dinitrophenylation, the lipids are hydrolyzed in ethanolic HCl . The hydrolysate is dried and dissolved in a solution of dimethylformamide-ethanol-n- butylamine, and tetramethylammonium hy- droxide is added. The ethanolamine and serine values are then determined by differ- ential color measurement at 393 mu. and
500 m
y>,
Collins, F. D.
1959. Studies on phospholipids. 5. The separation of dinitrophenylated and methylated phospholipids by counter - current distribution. Biochemical Journal, 72: 281-287. A method is described for the separa- tion of phospholipids from sheep and rat brain lipids by counter-current distribu- tion of their dinitrophenyl and methyl de- rivatives in several solvent systems.
Colman, D. M. and A. F. McPhee
1956. An improved method for deter- mination of total serum cholesterol. American Journal of Clinical Pathol- ogy, 26: 181-186. Direct saponification of the serum sample, extraction of the cholesterol, precipitation with digitonide, and color development with a modified Liebermann-Burchard reagent are all carried out in the same tube. Accu- racy and precision are good,
Corcoran, G. B.
i^ 1956. Chromatographic separation and
# determination of straight -chain satu-
rated monocarboxylic acids C^ through Cjo ^i^d dicarboxylic acids C, , through
^16- The acids were separated by chromato- graphy on a glycine -buffered column of si- licic acid using a 1-butanol -chloroform mo- bile phase. Accuracy is+ 1%.
Cormier, M. and P. Jouan
1957. Separation of lipides by chroma- tography on paper impregnated with si-
_. licic acid. Bulletin de la Societe de
* chimie biologique, 39: 1321-1327. Chemical Abstracts, 53: 11491a (1959).
A method for the separation of lipids by chromatography on silicic acid-impreg- nated filter paper .
Cormier, M. and P. Jouan
1958. Separation of the total lipides of "^ blood serum by chromatography on
# paper . Bulletin de la Society de chimie A biologique, 40: 171-176. Chemical Ab- ■ stracts, 53:18146b (1959).
A method is described for the separation of serum lipids by chromatography on silic- ic acid impregnated paper. The phospho- lipids are first separated by chromatography with a Et20-petroleum ether -Me2CO(2: 100:50) solvent mixture, and the glycerides, ster- oids, and cholesterol are then separated by using Et20-petroleum ether -heptane (4:50:50).
Cormier, M., P. Jouan, and L. Girre
1959. Separation of lipides by chroma- tography on paper impregnated with si-
. licic acid. II. Possibilities and Umita-
2. tions of the method. Bulletin de la So-
ciete de chimie biologique, 41: 1037- " 1046. Chemical Abstracts, 54:4736e
(1960). Lipids were separated into steroid, tri- glyceride, and mono- and diglyceride groups by chromatography on Si02~ impregnated paper using an ether -petroleum ether -hep- tane (8:50:50) solvent mixture. The appli- cations of the method are discussed.
Comer, M.
1959. Rapid microdetermination of organ- A ically bound halogens, arsenic, phos-
phorus, and boron. Analyst, 84: 41-46.
14
The sample is combusted in O (Schoniger, Helvetica chimica acta, 39: 650, 1956), and phosphorus is precipitated as quino- line molybdophosphate and titrated.
Cotte, J. and E. Kahane
1950. The determination of choline as trimethylamine . Bulletin. Societe chimique de France, 639-648. Chem- ical Abstracts, 45:1641e (1951)"! The method consists of oxidation of cho- line by KMnO- in the presence of Na2S405 and measurement of the formaldehyde for- med.
Courchaine, A. J., W. H. Miller, and D. B. Stein, Jr.
1959. Rapid semimicro procedure for
_ estimating free and total cholesterol.
Clinical Chemistry, 5: 609-614. A modification of the method of Zlatkis, Zak, and Boyle (Journal of Laboratory and Clinical Medicine, 41: 486, 1953). Phos- phoric acid is used as solvent for ferric chloride, giving a stable color reagent. The method compares well with methods of Schoenheimer-Sperry (Journal of Biolog- ical Chemistry, 106: 745, 1934) and Abell, et al (Journal of Biological Chemistry, 195: 357, 1952).
Craig, B. M. and N. L. Murtz
1958. The separation of saturated and k unsaturated fatty acid esters by gas-
^ liquid chromatography. Canadian Jour-
nal of Chemistry, 36: 1297-1301. Fatty acid methyl esters are separated according to chain length on a silicone grease column and according to chain length and degree of unsaturation on a plasticizer column using a firebrick support and helium as the carrier gas.
Crawford, N.
1959. Determination of serum oCand /3 lipoprotein cholesterol. Clinica Chim-
■ ica Acta, 4: 494-502 . Chemical Ab-
stracts, 53: 20208h (1959). Lipoproteins are separated by paper elec- trophoresis and their cholesterol is estima- ted using FeCl3.
Cremer, H. D.
1949. Tetrahydrofuran as extraction agent for lipide determination in blood ■^ and serum . KUnlsche Wochenschrift,
# 27: 755, Chemical Abstracts, 44: 8986d (1950).
A method is described which is similar to Bloor's method, but which uses hot tetra- hydrofuran for extraction of blood or serum lipids . The method gives higher values than Bloor's method.
Crombie, W. M. L., R. Comber, and S. G. Boatman
1955. The estimation of unsaturated _. fatty acids by reversed-phase parti-
tion chromatography. Biochemical
# Journal, 59: 309-316.
Unsaturated fatty acids were sefiarated on paraffin -impregnated kieselguhr using ace- tone-water mixtures for elution. Effects of isomerism and functional groups on the rates of elution are discussed.
Davenport, J. B.
1955. Column partition chromatography ^ of the fatty hydroxamic acids. Chem-
# istry and Industry (London) 705-706. Fatty acid hydroxamates were separated
on a cellulose column and identified by their melting points .
Dawson, R. M. C.
1954. A note on the estimation of sphingo-
myelin in nervous tissue . Biochemical
Journal, %: 621-625. Lower values for sphingomyelin were ob- tained by the method of Schmidt, et al (Jour- nal of Biological Chemistry, 166: 505, 1946) when the lipids in brain tissue were precip- itated with trichloracetic acid prior to sol- vent extraction. The cause is believed to be the presence of phosphorus -containing ma- terials which become insoluble in trichlor- acetic acid after alkaline hydrolysis and are therefore estimated as sphingomyelin.
DeLorenzi, F. and R. Aldrovandi
1952. Volumetric determination of phos- phorous in phosphates, glycerophos- ▲ phates, and lecithin with Complexon III.
Farmaco, scienza e tecnlca (Pa via) 7:
15
309-312. Chemical Abstracts, 46: 11036b (1952). Phospholipid is precipitated with a meas- ured amount of MgCl2 "61120 in the presence of NH4 salt and NH3, and excess Mg is ti- trated with Complexon III.
Delsal, J. L.
1944. New procedure for extraction of serum lipides with methylal. Applica- tion to microdetermination of total cho- . lesterol, phosphoaminolipides and pro-
teins. Bulletin de la Societe de chimie biologique, 26: 99-105. Chemical Ab- stracts, 39:356CP (1945).
Extraction of serum cholesterol and lipids with methylal was found to be complete .
Delsal, J. L.
1946. Colorimetric microdetermination of free cholesterol . Bulletin de la So-
■ ciete de chimie biologique, 28: 441-445. Chemical Abstracts, 41:4188a (1947).
A method is described for the determina- tion of free cholesterol by precipitation with natigen and measurement by the Liebermann- Burchard reaction.
Delsal, J. L.
1950. Extraction of cholesterol from
blood serum by chloroform in the pres- ence of anhydrous sodium sulfate or
■^ plaster of paris. Compte rendu hebdo-
■ madaire des seances et m^moires de la Socigtfe de biologie, 144: 67-69. Chem- ical Abstracts, 44:100241(1950).
Cholesterol is not completely extracted from serum which is dehydrated with an- hydrous sodium sulfate unless the serum is first hydrolyzed with NaOH.
Delsal, J. L. landMme. DeMont-Argant
1950. Accord between the colorimetric
and gravimetric (by natigin or digitonin) determinations of cholesterol in normal and pathological human serum. An a- nomaly observed with certain lipoid nephrosis serums. Compte rendu heb- domadaire des seances et mfemoires de la Societe de biologie, 144: 87-89. Chemical Abstracts, 44:10024g (1950). Cholesterol values obtained by colorimet-
ric microdetermination after saponification usually agree with those obtained by gravi- metric determination.
Delsal, J. L.
1954. Fractionation of the lipides of blood serum by organic solvents. . Bulletin de la Societe de chimie biolog-
ique, 36: 1329-1334. Chemical Ab- stracts, 49:7628a (1955). A methylal -methanol (4:1) mixture is used to precipitate protein and extract the lipids from a serum sample. Petroleum ether and water are added to the extract to cause the extract to separate into two phases. Ster- ides and triglycerides concentrate in the up- per phase, and phosphoaminolipides in the lower .
Devis, R.
1944. Acidimetric determination of total fat acids in very small quantities of bio- logical fluids and tissues. Bulletin de la % Societe de chimie biologique, 26: 232-
238. Chemical Abstracts, 40:1190^ (1946). Lipids are hydrolyzed and acidified to free the fatty acids. The acids are extracted with benzene and titrated with KOH .
Dieckert, J. W. andR. Reiser
1956. A paper chromatographic proce- dure for separating 1-mono-, 1,3-di-, ■^ and triglycerides, cholesterol, and cho-
# lesterol esters. Journal of the American
■ Oil Chemists Society, 33: 123-126.
Chemical Abstracts, 50:7012g (1956). 1-mono, 1,3-di-, and triglycerides, cho- lesterol, and cholesterol esters were sepa- rated by chromatography on silicic acid-im- pregnated glass fiber paper using ethyl ether- isooctane mixtures as solvents. Spots on the developed chromatogram were detected by spraying with 50% aqueous H2SO. and gen- tle heating to detect cholesterol-containing lipids, followed by stronger heating to de- tect the glycerides. Degree of unsaturation of the glyceride fatty acids had no detect- able effect on the R, values of the triglycer- ides.
The glass paper was specially washed in MeOH and ethyl ether to remove impurities .
16
The dichromate-H2S04 reagent used earli- er by Fillerup and Mead (Proceedings of the Society for Experimental Biology and Medicine, 83: 574, 1953) gave yellow -or- ange background color, and did not permit differentiation between cholesterol- and non-cholesterol -containing lipids.
Dieckert, J. W. and R. Reiser
1956. Paper chromatography of phospho- lipides on silicic acid impregnated -^ glass fiber filter paper. Journal of the
A American Oil Chemists Society, 33:
535-537. Phospholipids were separated from their mixtures by chromatography on glass paper impregnated with silicic acid using 1:1 methanol -ethyl ether as solvent.
Dijkstra, G., J. G. Keppler, and J. A. Schols
1955. Gas-liquid partition chromatogra- phy. Recueil des travaux chimiques
•^ des Pays-Bas et de la Belgique, 73:
0 805-812. Chemical Abstracts, 50:
1528f (1956). A silicone grease- or paraffin -coated column of celite was used to separate mix- tures of medium chain fatty acids, alcohols, and aldehydes . Other gas chromatographic systems for identification and determina- tion of aliphatic materials are described.
Dittmer, J. C, J. L. Feminella, and D. J. Hanahan
1958. A study of the quantitative estima- tion of ethanolamine and serine in the ▲ phospholipids. Journal of Biological
Chemistry, 233: 862-867. The phospholipids are hydrolyzed with 6 2^ HCl, and the free amines are separated by ion exchange . Ethanolamine and serine are estimated as NH released by periodate oxidatio"n of the amines.
Dole, V. P.
1956. A relation between non-esterified fatty acids in plasma and the metabolism
0 of glucose . Journal of Clinical Investi-
gation, 35: 150-154. Non-esterified fatty acids are extracted with i so -propyl alcohol-heptane-1 N H2SO4 and titrated with 0.018 N NaOH. The meth-
od measures fatty acids in 1 cc. of plasma to + 3% in replicate analyses.
Drekter, I. J., A. Bernhard, and J. S. Leopold
1935. The extraction of cholesterol from blood serum . Journal of Biological Chemistry, 110: 541-549.
It was found that alcohol extracts all of the cholesterol from blood serum, while ether only extracts a small part of it. Part of the cholesterol is presumably bound to protein which is denatured by the alcohol, thus allowing complete extraction with alco- hol.
Drekter, I. J., A. E. Sobel, and S . Natelson
1936. Fractionation of cholesterol in blood by precipitation as pyridine cho- lesteryl sulfate and cholesterol digiton- ide . Journal of Biological Chemistry, 115: 391-399.
It was found that the pyridine sulfate meth- od (Sobel, Journal of Biological Chemistry, 115: 381, 1936) gave free cholesterol values from 6 to 10% of the total, while for the cho- lesterol digitonide method the value was 25 to 35%. The theory is advanced that the dig- itonin method may give higher values due to splitting of loosely bound cholesterol or the precipitation of some form of combined cholesterol other than fatty acid esters .
Ducet, G. andE. Kahane
1946. Biochemistry of choline and its derivatives. XX. Identification and chemical determination of choline in biological substances. Bulletin de la
Societg de chimie biologlque, 28: 794- 805. Chemical Abstracts, 41^ 4188b (1947). After decomposition of the tissue with HNO3, choline is freed by hydrolysis and precip- itated by I„KI or phosphotungstic acid and determined in the precipitate .
Ducet, G.
1948. Separation and determination of the water-soluble forms, of choline. Analytica Chimica Acta, 2: 839-843.
(in French). Chemical Abstracts, 43: 7998b (1949). ~~
Free choline is adsorbed on silica gel,
17
and the combined water-soluble choline in the effluent is hydrolyzed and deter- mined separately as the periodide .
Duffie, M. J. and J. L. Guravich
1959. A comparison of the methods of
Bloor and Schoenheimer-Sperry in the
estimation of cholesterol in serum.
American Journal of Clinical Pathology,
32: 92-96. Serum cholesterol determinations by the Bloor (Journal of Biological Chemistry, 24: 227, 1916) and the Sperry and Webb modifica- tion (Journal of Biological Chemistry, 187: 97, 1950) of the Schoenheimer-Sperry meth- od were done in parallel. The Bloor method yielded values which were 1.044 times as large as comparable values by the S-S meth- od. The Bloor method appeared to be as accurate, and was faster than the S-S meth- od.
Dutton, H.J. and C . L . Reinbold
1948. Adsorption analysis of lipides. in. Synthetic mixtures of ethyl stear- ic ate, oleate, linoleate, and linolenate . ^ Journal of the American Oil Chemists • Society, 25: 120-124. Chemical Ab- stracts, 42:3973f (1948). Details are given of a study of adsorp- tion analysis of binary mixtures of ethyl stearate, oleate, linoleate, and linolenate on alumina columns .
Edman, P. V.
1942. A micromethod for the estimation of cerebrosides in nerve tissue. Jour- nal of Biological Chemistry, 143: 219- 221. The carbazole reaction of Dische (Mikro- chemie, 8: 4, 1930) is used for the quantita- tive estimation of 0.2 to 0.6 mg. of cerebro- sides by colorimetry. After hydrolysis of the cerebrosides, the fatty acids are remov- ed by virtue of their Insolubility in water, and glycerol is extracted into ethyl acetate. Noll's (Zeltschrift fur physiologische Chemie, 27: 370, 1899), Kimmelsteil's (Blochemische Zeltschrift, 212: 359, 1929), and Kirk's (Journal of Biological Chemistry, 123fc 613, 1938) methods for estimation of galactose set free from the cerebrosides by
hydrolysis are criticized for their lack of specificity In reduction methods.
Edman, P. V. andS. E. G.Aqulst
1945. A micromethod for the estimation of phosphatidyl ethanolamlne in nerve ▲ tissue. Acta physlologlca Scandlnavica,
20: 144-149. Phosphatidyl ethanolamlne is estimated as ethanolamlne by hydrolysis of an alcoholic tissue extract, distillation of the ethanol- amlne, and colorlmetric measurement of the blue color developed with sodium hypo- chlorite and phenol.
Edsgaard, J.
1948. On the determination of the phos- phatide content of serum. Acta physlo- loglca Scandlnavica, 16: 171-178. An investigation of methods for the deter- mination of serum phospholipid. It was found that absolute ethanol alone is as effec- tive for the extraction of serum phospho- lipids as alcohol-ether (3:1) or alcohol- acetone (1:1). Temperature and time of ex- traction are not critical as long as 1:20 ratio of serum to solvent is maintained.
Edsgaard, J.
1948. On the colorlmetric determination of phosphorus with "amidol" . Acta A physlologlca Scandlnavica, 16: 179-
182. A discussion of the effects of variables in the determination of phosphorus with "ami- dol" (diaminophend hydrochloride) and molyb- date. Acidity and temperature of color de- velopment were found to be Important, but age of the reagents had little effect.
Ellis, G. and L. A. Maynard
1937. TTie determination of phospholipids in bovine blood. Journal of Biological
^ Chemistry, 118: 701-709.
The values for Bloor's oxidative technique (Journal of Biological Chemistry, 82: 273, 1929) were found to be variable and also 50% or more below values obtained by the lipid phosphorus method (method not stated). The values for phospholipid found in the final moist ether (or chloroform) solution after the purification steps of Bloor, however.
18
were in good agreement whether obtained by the oxidative procedure or by multiply- ing the phosphorus present by the factor 25. It was found that the temperature of evapora- tion of the alcohol -ether extract affects the solubility of the phospholipids in petroleum ether; therefore the use of a vacuum and temperature of less than 50° is recommend- ed for the evaporation. CHCI3 dissolves the phospholipid-MgCl2 precipitate as well as moist ether, giving more consistent results and requiring less time for solution. Alco- hol-ether extracts of plasma, when stored for several months gave ratios of lipid phos- phorus, phospholipid, and phospholipid fatty acid no lower than extracts used a few days after preparation . See also: Boyd (Journal of Biological Chemistry, 121: 485, 1937) and Halliday (Journal of Nutrition, 16: 285, 1958).
Engel. R. W.
1942. Modified methods for the chemical
and biological determination of choline .
Journal of Biological Chemistry, 144:
701-710. Choline was extracted from biological material by continuous extraction with meth- anol, which is claimed to be the most ef- fective solvent (obtained recoveries within 1.5% of theoretical) . (Brante (Acta physio - logjca Scandinavia,^- supplement 63, 1949) states that ethanol-ether (3:1) is just as ef- fective as methanol). The extract was con- centrated and hydrolyzed with Ba(OH)p at 100° C. (100° was used since the tempera-* ture of 80° suggested by Jacobi (Journal of Biological Chemistry, 138: 571, 1941) fail- ed to give consistent results.) Choline was determined as the reineckate by colorimetry. The incidence of kidney hemmorhage in rats was also used as an indication of the quantity of choline and choline-like materials in bio- logical test diets, and showed sensitivity to a variation of 10% of the materials .
Engel, R. W., W. D.Salmon, and C.J. Ackerman
1954. Chemical estimation of choline. In Methods of Biochemical Analysis, D. Click, Editor, New York, Inter- science Publishing, Inc., Vol. 1,
pp. 265-286. A study and discussion of various meth- ods for the estimation of choline in tissues.
Entenman, C, A. Tkurog, and I. L. Chaikoff
1944. The determination of choline in phospholipids . Journal of Biological Chemistry, 155: 13-18.
The phospholipids were hydrolyzed with Ba(OH)2 and the choline was precipitated . as the reineckate and read colorimetrically. Accuracy j- 3% using choline chloride.
1 .2 N HCl was used as solvent for ammo- nium reineckate, making it possible to use a more concentrated reineckate solution. Precipitation is complete in 30 minutes.
Entenman, C . and I . L . Chaikoff
1945. On the determination of choline in the liver and plasma of the dog. Jour-
A nal of Biological Chemistry, 160: 377-
385. Various extracts and fractions of plasma and liver were analyzed for choline by the methods of Click (Journal of Biological Chemistry, 156: 643, 1944) and of Enten- man, et al (Journal of Biological Chemistry, 155: 13, 1944). Identical choline values were found for the phospholipid fraction 1- solated from either liver or plasma when the precipitations of choline reineckate were carried out in the presence of 1 .2 N HCI (Entenman, et al) or at a pH between 8 and 9 (Click). Both methods gave values in agreement on analyses of both alcohol - ether and methanol extracts of plasma, but Click's method gave lower values for an alcohol -ether extract of liver.
Erickson, B. N., I. Avrin, D. M. Teague, and H. H. WiUiams
1940. Micromethods for the determination of sphingomyelin and choline. Applica- tions for the estimation of the phospho- lipid partition (sphingomyelin, lecithin, and cephalin) in blood and urine . Jour- nal of Biological Chemistry, 135: 671- 684. A procedure is described in which sphingo- myelin is precipitated as the reineckate and calculated from the phosphorus content of the reineckate. Choline is determined, after
19
hydrolysis of the phospholipids, by precip- itation as the enneaiodide, conversion of the iodide to iodate with bromine, and ti- tration with sodium thiosulfate. Compar- ison of Ba(0H)2 and methanolic HCl hydrol- ysis techniques showed nearly identical values with phospholipids of approximately 25% sphingomyelin content. With those of over 50% sphingomyelin, the methanolic HCl method gave values 10% higher.
Fairbairn, D.
1945. Free fatty acids in animal tissues. _ Journal of Biological Chemistry, 157:
• 645-650.
A rapid loss of phospholipids occurs shortly after tissue is removed due to autolysis (approximately 8% in a few min- utes in whole cat liver; approximately 15% in ground liver). Homogenization in alco- hol or fast-freezing decreases autolysis.
Farvarger, P. and J. Gerlach
1958 . A quantitative evaluation of
Twitchell's method for the separation . of saturated and unsaturated fatty acids.
^ Archives des sciences (Geneva), II;
* 539-542. Chemical Abstracts, 53; 19075h (1959).
Twitchell's lead salt operation method (Journal of Industrial and Engineering Chemistry, 13: 806, I92I) was used to separate the fatty acids of the mouse into saturated and unsaturated fractions . Re- coveries were followed by addition of C labelled fatty acids. Recoveries ranged from 84.2 to 95.7%.
of Clinical Pathology, 23: 599-602. Cholesterol is precipitated as the digito- nide, and the digitonide is quantitatively determined by measurement of the color produced with anthrone reagent.
Feulgen, R . and H . Grunberg
1939. Estimation of plasmal (plasma - logen) in lipoid mixtures and in organs. ^ Zeitschrift fiir physiologische Chemie,
257: 161-172. Chemical Abstracts, 33:3407^ (1939). Plasmalogens in lipid mixtures were de- termined by photometric measurement of the color produced with fuchsin-sulfurous acid reagent.
Feulgen, R., W. Boguth, and G . Anderson
1951. Determination of acetal phospha- tide (plasmalogen) in serum with regard to the Waelsch effect. Zeitschrift fiir ^ physiologische Chemie, 287: 90-108.
Chemical Abstracts, 48: 462 Ig (1954). Acetal phosphatide of serum is determin- ed by hydrolysis with HCl in an acetic acid solution, neutralization with NaOH, and de- velopment of color with SO2 -reduced fuchsin.
Fillerup, D. L. and J. F. Mead
1953. Chromatographic separation of the . plasma lipids . Proceedings of the Soci-
^ ety for Experimental Biology and Medi-
* cine, 83: 574-577.
Plasma lipids were separated into groups by chromatography on silicic acid with ethyl ether -petroleum ether and methanol -ethyl ether as eluting solvents.
•
▲
Faure, M.
1950. Method for purification of lecithins. Bulletin de la Societ§ de chimie biolog- ique; 32: 503-508. Chemical Abstracts, 45:695F(I95I). Lecithin was purified by precipitation with CdCU. removal of Cd, precipitation from ether with Me2C0, extraction with ether, evaporation, and chromatography of the ether solution on alumina .
Feichtmeir, T. V. and J. Bergerman
1953. Indirect colorimetric determina- tion of cholesterol. American Journal
Fink, K. and R. M. Fink
1949. Application of filter paper parti- tion chromatography to quantitative 4_ analysis of volatile and non-volatile
_ organic acids. Proceedings of the Soci-
ety for Experimental Biology and Medi- cine, 70: 654-656. The Cj-Cg acids are chromatographed on filter paper as their potassium hydroxamates and located on the developed chromatogram by spraying with ferric chloride solution .
Fiske, C . H . and Y . Subbarow ▲ 1925. The colorimetric determination of
20
phosphorus. Journal of Biological Chemistry, 66: 375-400.
Aminonaphtholsulfonic acid is used for reduction of phosphomolybdic acid in the presence of bisulfite in place of the hydro- quinone used in earlier methods. Effects of interfering substances and variations in reagent concentrations on the development of color are discussed.
The method is suitable for colorimetric determination of inorganic and total phos- phate in a variety of biological materials .
Fitelson, J.
1950. A new oxidation method for the determination of saturated fatty acids . _ Journal of the American Oil Chemists
Society, 27: 1-8. Chemical Abstracts, 44:2259f (7950) . Saturated fatty acids are purified by chromatography on alumina after oxidation of the unsaturated acids with performic acid and extraction of the oxidation products with petroleum ether.
Fleckenstein, A., E. Gerlach, and J. Janke 1953. Rapid test for identification of easy and difficultly hydrolyzable phos- phoric esters in paper chromatogram , Naturwissenschaften, 40: 462. Chem-
Fleury, P. andH. Guitard
1948. Determination of choline in leci- thin. Annales pharmaceutiques fran-
A caises, 6: 252-254. Chemical Ab-
stracts, 43:5344h (1949). Choline is determined colorimetrically as the reineckate.
Fleury, P., J. Courtois, and M. Grandchamp
1949. Estimation of mixtures of cola- mine and serine. Biochimica et bio-
ical Abstracts, 48:8124g (1954). The chromatogram is sprayed with molyb- date reagent and exposed to H2S, which turns spots containing P to a blue color . Exposing the paper to NH3 vapor causes the color to disappear from the spots caused by phos- phoric esters which are difficult to hydro - lyze, while the spots from inorganic P or readily hydrolyzed esters remain blue .
Fleury, P. andR. Paris
1933. , A comparison of the action of periodic acid on the CC and /3 glycero- phosphoric acids. Compte rendu, 196: 1416-1418. Chemical Abstracts, 2^ 3915 (1933). A confirmation of earlier findings that oxidation by HIO4 of a compound having several alcoholic groups does not take place unless these groups are adjacent.
physica Acta, 3: 336-340. (In French). Ethanolamine and serine are estimated by determination of the NH3 liberated and the amount of periodic acid reduced during 48 hours of standing at room temperature.
Folch, J. and D. D. van Slyke.
1939. Nitrogenous contaminants in pe- troleum extracts of plasma lipids. Journal of Biological Chemistry, 129: 539-546. Urea is the primary N-containing con- taminant of petroleum extracts of plasma lipids. Although urea is- insoluble in pe- troleum ether, it is dissolved in a lipid ex- tract of petroleum ether, presumably due to the solvent effect of the lipids .
Folch, J. and D. D. van Slyke
1939. Preparation of blood lipid extracts free from non-lipid extractives. Pro- ■Ar ceedings of the Society for Experiment -
al Biology and Medicine, 41: 514-515. Proteins and lipids are precipitated to- gether with colloidal iron and washed with HjO, and the lipids are extracted with alco- hol-ether. Brante (Acta physiologlca Scan- dinavica, 18 (supplement 63): 1, 1949), and Sperry (Journal of Biological Chemistry, 170: 675, 1947) found that a considerable amount of lipid material is lost by this method of purification .
Folch, J.
1941. Isolation of phosphatidyl serine from brain cephalin and identification ▲ of the serine component. Journal of
Biological Chemistry, 139: 973-974. Phosphatidj^l serine is separated from brain cephalin by precipitation of the ce- phalin in alcohol -chloroform, and the
21
serine component is removed by 30 hour HCl hydrolysis and crystallization from ab- solute alcohol.
Folch, J.
1942. Brain cephalin, a mixture of phos- phatides. Separation from it of phos- . phatidyl serine, phosphatidyl ethanol-
amine, and a fraction containing an ino - sitol phosphatide. Journal of Biological Chemistry, 146: 35-43. Phosphatidyl serine, phosphatidyl ethanol- amine, and an inositol phosphatide were separated by their differences in solubility in chloroform and alcohol .
Folch, J. and D. W. WooUey
1942. Inositol, a constituent of brain phosphatide. Journal of Biological Chemistry, 142: 963-964. Inositol is separated by precipitation and HCl hydrolysis. Inositol is found in brain in combined form .
Folch, J.
1948. The chemical structure of phos- ■^ phatidyl serine. Journal of Biological ▲ Chemistry, 174: 439-450.
A method is described for the isolation of phosphatidyl serine of at least 92% puri- ty by means of precipitation, dialysis, and solvent recrystallization procedures.
Folch, J.
1949. Complete fractionation of brain cephalin; isolation from it of phos-
. phatidyl serine, phosphatidyl ethanol-
amine, and diphosphoinositide . Jour- nal of Biological Chemistry, 177: 497- 504. The cephalin fractions are separated by their different solubilities in organic sol- vents.
washing with water . The method was com- pared with those of Brante (Acta physiolog- ica Scandinavica, 18 (supplement 63): 1, 1949) and McKibbin and Taylor (Journal of Biological Chemistry, 178: 17, 1949). It was found that this method extracted more strandin and proteolipids than the other methods, but that the extraction of other lipids and removal of non -lipid contami- nants from the extracts were essentially the same for all three methods.
Sperry (Journal of Biological Chemistry, 209: 377, 1954) found no significant differ- ence in his own method and Folch' s, but his final material was completely soluble in chloroform -methanol (2:1) while Folch's method left a small insoluble residue .
Folch, J., M. Lees, and G. H. Sloane -Stanley 1957. A simple method for the isolation
_, and purification of total lipids from
2 animal tissues. Journal of Biological
• Chemistry, 226: 497-509.
A simplification of the procedure of Folch, et al (Journal of Biological Chemis- try, 19lT833, 1951).
Tissue lipids are extracted with CHCI3- MeOH (2: 1) and the extract is purified by washing with aqueous salt solutions.
Forbes, J. C. and T. T. Atkinson, Jr.
1943. The separate determination of the fatty acid fraction and of the neutral 9 fat plus sterol fraction in feces. Jour-
nal of Laboratory and Clinical Medicine, 28: 1507-1510. The fat is extracted and iS separated into free fatty acid and neutral fat fractions by precipitation of the free fatty acids as their Na soaps. The separate portions are then determined by oxidation with silver chromate and iodometric measurement of excess di- chromate .
Folch, J., I. Ascoli, M. Lees, J. A. Meath, and F.N. LeBaron
1951. Preparation of lipide extracts from , brain tissue. Journal of Biological
* Chemistry, 191: 833-841.
Lipid Extracts are prepared by homogen- izing brain tissue with CHCl3-MeOH (2:1), filtering to remove insoluble matter, and
Foreman, H. D. and J. B. Brown
1944. Solubilities of the fatty acids in organic solvents at low temperatures. • Oil and Soap, 21: 183-187. Chemical
(1944).
Abstracts, 38:4821
Data is given on the solubility in several organic solvents of various saturated and unsaturated fatty acids at temperatures
22
ranging from 10° to -70°.
Foulger, J. H.
1932. Two new color tests for hexoses . Journal of Biological Chemistry, 99: 207-211. Urea or guanidine is used in a SnC^ - H2SO4 solution to give a color reaction with simple hexoses. The urea reagent differentiates between aldo- and keto- hexoses, and the guanidine reagent gives a distinct color for each sugar but does not distinguish between aldo- and keto- hexoses. Sensitivity varies from 0.02 to 0.5 mg. depending on the sugar tested.
Frampton, V. L., R. D. Maseles, and G.N. Martin
1948. Lipides of the cottonseed. III. Perchloric acid ashing of lipides for the determination of phosphorus. Jour- ▲ nal of the American Oil Chemists Soci-
ety, 25: 219-220. 42:5689f (1948).
Chemical Abstracts,
The presence of HCIO4 does not interfere with development of molybdenum blue color in the determination of phosphorus by the Fiske-Subbarow method.
Franzke, C . and G . Ittrich
1947. Determination of linoleic and linolenic acid by means of bromine ■A" addition . Fette, Seifen, Anstrich-
# mittel, 59: 740-744. Chemical Ab- stracts: 53:185121 (1959).
Linoleic and linolenic acids are separated as their bromine addition products by using the difference in their solubilities in petro- leum ether.
Freeman, N. K., F. T. Lindgren, Y. C. Ng, and A . V . Nichols
1957. Serum lipide analysis by chro- . matography and infrared spectrophoto-
_ metry . Journal of Biological Chemistry,
• 227: 449-464.
Lipids are separated into three fractions on a silicic acid-Celite column, and cho- lesteryl esters, glycerides, total phospha- tides, cholesterol, and free fatty acids are estimated by infrared absorption measure- ments. A 1 ml. sample of serum (5-10 mg.
of total lipids) is used. A component of at least 0.5 mg. is estimated to + 10% .
Fries, J., A. Holasek, andH. Lieb
1956. Detection of unsaturated fatty acids on a paper chromatogram . Mikro-
• chimica Acta, pp 1722-1726. Chemical Abstracts, 51:4215b (1957).
Unsaturated fatty acids on a paper chro- matogram are made visible by exposing the chromatogram to ozone and spraying with fuchsin-sulfurous acid.
FriseU, W. R., L. A. Meech, and C. G. MacKenzie
1954. A simplified photometric analysis for serine and formaldehyde. Journal of Biological Chemistry, 207: 709-716. The formaldehyde formed by oxidation of serine with periodate is measured by direct photometry without distillation.
Fugger, J., J. A. Cannon, K. T. Zilch, and H. J. Dutton
1951. Analysis of fat acid oxidation pro- ducts by countercurrent distribution . methods. IV. Methyl linolenate.
Journal of the American Oil Chemists
• Society, 28: 285-289. Chemical Ab- stracts, 45:106171(1951).
The oxidation products of methyl lino- lenate were fractionated by countercurrent distribution with aqueous ethanol and hexane as solvents.
Galloway, L. S., P. W. Nielson, E. B. Wilcox, and E. M. Lantz
1957. Micro -determination of cholesterol by use of 0 .04 ml . of blood serum .
" Clinical Chemistry, 3: 226-232.
A micro -adaptation of the method of Sperry and Webb (Journal of Biological Chemistry, 187: 97, 1950).
Garton, G . A . and A . K . Lough
1957. Analysis of mixtures of higher saturated normal fatty acids: A com- . pari son of re versed -phase partition
_ chromatography and ester fractiona-
tion. Biochimica et Biophysica Acta, 23: 192-195. The odd-numbered n-fatty acids were
23
separated on a dichlorodimethylsilane- treated column of silicic acid. Results compared well with ester fractionation methods .
Garvin, J. E. and M. L. Karnovsky
1955. Nonaqueous titration of lipids, with particular reference to phospha-
^ tides and related compounds . Proceed-
ings of the International Conference on Biochemical Problems of Lipids, 2nd Ghent, (Pub. 1956) pp. 14-16. The use of 99% ethoxyethanol as a solvent for titration of small amounts of fatty acids is discussed.
Gertler, M. M., J. Kream, and O. Baturay
1954. Studies on the phosphatide content of human serum. Journal of Biological ^ Chemistry, 207: 165-173.
Phosphatides were extracted from serum and hydrolyzed with 6 N HCl for 48 hours at 100°, and the free bases were separated by paper chromatography. Serine and ethanolamine were located on the chroma - togram with ninhydrin and extracted with pyridine. The optical density of the pyri- dine solutions was determined spectrophoto- metrically at 580 mf». Choline was treated on the paper with phosphomolybdic acid- stannous chloride and the spot areas were measured by planimetry.
Gibble, W. P., E. B. Kurtz, Jr., and A. E. Kelley
1956. A semi-micro procedure for the separation and degradation of long-
"^ chain fatty acids . Journal of the Amer-
# ican Oil Chemists Society, 33: 66-68.
Chemical Abstracts, 50:5309b (1956). Total lipid is extracted with petroleum ether and saponified by refluxing for 6 hours with 12% alcoholic KOH. The fatty acids are freed with HCl and extracted with ether . The ether is evaporated and the fatty acids are dissolved in acetone and separated by low temperature crystallization. Unsat- urated fatty acids are hydrogenated using Pt02 in absolute ethanol. Saturated fatty acids are degraded using thionyl chloride, pyridine, and AICI3 .
Click, D.
1944. Concerning the reineckate method for the determination of choline . Jour- nal of Biological Chemistry, 156: 643- 651. No significant difference in result was ob- tained by the purification of neutralized Ba(0H)2 hydrolysates of wheat germ ex- tracts by ether extraction or by adsorption of the choUne on Permutit and elution with salt solution according to Horowitz and Beadle (Journal of Biological Chemistry, 150: 325, 1943). Choline reineckate was washed free of excess Reinecke salt with n-propanol.
Goddu, R. F., N. F. LeBlanc, andC. N. Wright 1955. Spectrophotometric determination of esters and anhydrides by hydroxamic
# acid reaction . Analytical Chemistry, 27: 1251-1255.
A method is described for determination of esters by conversion to their hydroxamic acids and spectrophotometric measurement of the color produced by the ferric complexes of the acids . The effects of variables are discussed.
Goodwin, J. F.
1959. Total, phospholipide, and labile phosphorus in serum and tissue em- ploying chloric acid and n -phenyl -p- A phenylenediamine . Proceedings of the
Society for Experimental Biology and Medicine, 100: 217-219. A colorimetric method is described for determination of the phosphorus fractions of serum. Chloric acid is used for diges- tion, and the phosphomolybdate complex is reduced with p-semidine . The method has the advantages of ease of digestion and color development, and stability of the color complex. It compares well with the Fiske- Subbarow method.
Gorbach, G. and A. Jurinka
1944. Micromethods for fats. DC. High- er saturated fatty acids by the Bertram
• method. Fette und Seifen, 5]_:171-173. Chemical Abstracts, 42:9204f (1948).
A description of micromodifications of Bertram's method (Zeitschrift fur Unter-
suchung der Lebensmittel, 55: 179, 1928).
24
Gortoer, W. A.
1945. An evaluation of micromethods for phospholipid. Journal of Biological ^ Chemistry, 159: 97-100.
Analyses of tissue by determination of lipid phosphorus, by oxidation of the fatty acids from acetone -insoluble lipids, and by direct oxidation of the intact phospholipid are compared.
When a phospholipid to phosphorus ratio of 24 is used, and a fatty acid recovery of 63% of the weight of the saponified phospho- lipid was assumed, the three methods gave comparable results. Phosphorus analysis, however, gave better agreement among replicate samples (error + 0.8%) than either of the oxidative procedures studied (error + 2.2% and + 2.1%).
The author cautions against the use of conversion factors on mixtures of different types of phospholipid.
Gracian y Tous, J. and A. V. Pizarro
1947. Separation of higher fat acids by selective adsorption . Anales de fisica
* y quimica (Madrid), 42: 109-122.
~ Chemical Abstracts, 41:53231 (1947).
Alumina reacted chemically with oleic and stearic acids, making their separation on alumina difficult. Silicic acid was satis- factory as an adsorbent for the acids .
Graff, M . M . and E . L . Skau
1943. Colored chromatograms with hig^- er fatty acids . Industrial and Englneer- J ing Chemistry, Analytical Edition, 15:
• 340-341
Fatty acids were separated into zones by adsorption on magnesium oxide impregnated with phenol red. The column was sectioned after development and the fatty acids were recovered by dissolving the MgO in acid and extracting the fatty acids with ether . Sat- urated and unsaturated fatty acids of the same chain length and saturated fatty acids differing in chain length by 4 carbons were separable by the method.
Griswold, B. L., F. L. Humoller, and A. R. Mclntyre
1951 . Inorganic phosphates and phos- phate esters in tissue extracts. Ana-
lytical Chemistry, 23: 192-194. A modification of the Fiske-Subbarow (Journal of Biological Chemistry, 66: 375, 1925) method for reduction of phospho- molybdic acid with aminonaphtholsulfonic acid which uses the heating in 1 N H2SO4 recommended by Boltz and Mellon (Ana- lytical Chemistry, 19: 873, 1947) for color development. The higher acidity prevents color formation from reduction of free mo- lybdic acid as is possible in the Fiske- Subbarow method.
Gurin, S. and D. B. Hood
1939. The identification and estimation of hexoses in polysaccharides and gly- coproteins by the carbazole method. Journal of Biological Chemistry, 131: 211-223. The. carbazole reaction is used for quanti- tative identification of glucose, fructose, galactose, and mannose, or mixtures of these hexoses, by colorimetric measurement of the colors produced in sulfuric acid. Galactose and an equimolar glucose -mannose mixture give nearly identical values, so a supplementary test is necessary in these cases .
Hack, M. H.
1946. Some observations concerning sphingomyelin and sphingomyelin
▲ reineckate . Journal of Biological Chem-
istry, 166: 455-462.
Reineckates prepared from crude extracts contained both glycerol and hexose, implying the presence of other lipids than sphingo- myelin. The MeOH- soluble fraction of ceph- alln and the cerebrosides kerasin and phreno- sin formed reineckates. Recovery of pure sphingomyelins as the reineckates was low.
Values obtained by isolation of the sphingo- myelin were too low; and those obtained by the Reineckate method were too high, but there was general agreement in thg two meth- ods.
Hack, M. H.
1947. Estimation of the phospholipides in human blood. Journal of Biological Chemistry, 169: 137-143.
Lipids are extracted from 15 ml. of blood
25
with CHCl„MeOH (1:1) and total phospho- lipid is determined on an aliquot of the ex- tract. After saponification with 1 N KOH for 16 hours at 37° and acidification, cho- line is precipitated as the reineckate and determined colorimetrically at 526 m^. (Beer's Law did not hold at 327 m;^. under the conditions studied.) Sphingomyelin is calculated as the difference in total phos- phorus and that freed by hydrolysis. Leci- thin is calculated from the liberated choline, and cephalin is calculated as the liberated phosphorus minus lecithin.
Maximum precipitation of choline reineckate requires freshly prepared ammo- nium reineckate .
Hack, M. H.
1953. Analysis of lipids by spot tests on ▲ filter-disk chromatograms. Biochem -
■ ical Journal, 54: 602-605.
Spot tests are given for detection of quan- tities (3f 10"^ ^moles or less of choline lipids, amine lipids, plasmalogens, phos- phoric esters, cholesterol, glycolipids, and unsaturation on filter-disc chromatograms.
Hack, M. H.
1955. A method for the estimation of
fatty acid esters . Archives of Bipchem -
• istry, 58: 19-23.
A micro modification of the method of Bauer and Hirsch (Archives of Biochemistry, 20: 242, 1949).
The color produced by reaction of the hydroxamic acids from fatty acid esters with ferric perchlorate is determined col- orimetrically. Data on specificity and sensitivity are given. Estimates 0.2 to 3 ^.imoles of ester in a few minutes.
Halliday, N.
1938. Fatty livers in vitamin B^ defi- cient rats. Journal of Nutrition, 16:
• 285-290.
Storage of lipid extracts at room tem- perature resulted in losses of total fatty acids and phospholipid fatty acid. No change occurred in total cholesterol and a definite drop occurred in all iodine numbers. See also: Boyd (Journal of Biological Chem- istry, 121: 485, 1937).
•
Halliday, N.
1939. The effect of formalin fixation on liver lipids. Journal of Biological Chem- istry, 129: 65-69. A drop in iodine value and phospholipid fatty acids occurred in lipids stored in for- malin. There was little loss of total fatty acids during periods of up to three months, but longer storage caused a considerable loss.
Hamilton, J . G . and R . T . Holman
1954. Displacement analysis of lipids. 4^ X. Model mixtures of glycerides.
"^ Journal of the American Chemical
* Society, 76j 4107-4109.
Glyceride mixtures were separated on a Darco G-60 charcoal-Hyflo Super-Cel col- umn, using ethanol and benzene as eluting solvents.
Hanahan, D. J., M. B. Turner, andM. E. Jayko 1951 . The isolation of egg phosphatidyl choline by an adsorption column tech- nique. Journal of Biological Chemistry, 192: 623-628. Phosphatidyl choline is eluted from an alumina column with 95% ethanol as eluent. Rechromatography of the purer fractions yields a product of 99-100% pure phospha- tidyl choline.
Hanahan, D. J., J. C. Dittmer, and E. Warashina
1957. A column chromatographic separa- tion of classes of phospholipids. Jour- nal of Biological Chemistry, 228: 685- 700. A method is described for separation of the mixed phospholipids by elution with mix- tures of chloroform and methanol from a single silicic acid column. Recovery of lipid phosphorus is 88-95%, with 90-95% of inositol-containing phospholipids being eluted in one fraction. Reproducibility is good.
The use of gradient elution caused smear- ing of fractions. Cotton, when used as sup- port for the silicic acid, adsorbed approxi- mately 20% of the phospholipids, particular- ly the phosphoinositides, which were difficult to remove from the cotton.
*
26
An almost complete reversal in the elution pattern and overlapping of the eluted components occurred when the Hyflo Super-Cel filter aid was heated to 110° before use.
Hirsh (Journal of Biological Chemistry, 233: 213, 1958) also found that abrupt change of solvent yielded better separa- tions than gradient elution.
Handler, P.
1947. The determination of choline in biological material. Biological Sympo- sia, 12: 361-372. Chemical Abstracts, 41_:5lT7g(1947). Choline -containing lipid is extracted from tissue with methanol and hydrolyzed with Ba(OH)2 • The choline is precipitated as the reineckate and the precipitate is dissolved in acetone and measured colorimetrically.
Handschumaker, E. and L. Linteris
1947. A modified method for the deter- mination of monoglyceride in fats and oils by oxidation with periodic acid. # Journal of the American Oil Chemists
Society, 24: 143-145. Chemical Ab- stracts, 4]^:4659e (1947). Monoglycerides are determined by peri- odic acid oxidation and iodometric measure- ment of excess periodic acid.
Hanel, H . K . and H . Dam
1955. Determination of small amounts of total cholesterol by the Tschugaeff reaction with a note on the determina- tion of latho sterol. Acta chemica Scandinavia, 9: 677-682. A method is described for simultaneous determination of cholesterol and lathosterol (A -7-cholesterol). After hydrolysis with KOH and extraction with petroleum ether, the cholesterol in chloroform solution is treated with ZnCl2 in acetyl chloride and measured in a spectrophotometer at 528myLi. Lathosterol is read at 395 m/x., and gives almost no absorbance at 528 mu.
Hansen, P. W. and H. Dam
1957. Paper chromatography and colori- "^ metric determination of free and ester -
■ ified cholesterol in very small amounts
of blood. Acta chemica scandinavia, 11: 1658-1662. ~
Cholesterol is separated by paper chro- matography from substances which might interfere with color development by the method of Zlatkis, Zak, and Boyle (Journal of Laboratory and Clinical Medicine, 41: 486, 1958). The method can determine as little as 2.5 fig. of cholesterol and its esters with accuracy of +5%.
Harding, V.J. and C. E. Downs
1933. Notes on a Schaffer-Somogyi
copper reagent. Journal of Biological
Chemistry, 101: 487-492- A modified Somogyi copper reagent (Jour- nal of Biological Chemistry, 70: 599, 1926) is recommended as a good general sugar reagent. The reagent is prepared in two parts, and keeps for at least 3 months in the cold. Ammonium salts which interfere in the method are removed with HgSO^ and BaC03 .
Harris, W. D. and P. Popat
1954. Determination of the phosphorus content of lipids . Journal of the Amer- A ican Oil Chemists Society, ^: 124-127.
Chemical Abstracts, 48:6716g (1954). A method is described for determination of lipid phosphorus using perchloric acid digestion and elon(p-methylaminophenolsul- fate) as reducing agent for development of molybdate color . Effects of variables and disadvantages inherent in other methods are discussed.
Hartman, L.
1953. Rapid determination of glycerol by the potassium periodate method. Jour- nal of Applied Chemistry, (London) 3: 308-311. Chemical Abstracts, 48: 791 (1954).
Complete oxidation of glycerol by KIO4 takes place in 3 minutes when an excess of solid KIO4 is used.
Hartman, L.
1954. Determination of fat peroxides in the presence of phospholipides. Jour-
• nal of the Science of Food and Agricul-
ture, 5: 476-481. Chemical Abstracts,
27
49:27561 (1955). Peroxides were determined by reduction with FeClo in a benzene-methanol solution and determination of the Fe"^"^ produced by adding 2, 6-dichloroindophenol and H4P2O7.
Hartman, L.
1955. Analysis of glycerol . Chemistry and Industry (London) pp. 1407-1408. Chemical Abstracts, 50:2370a (1956).
The glycerol sample is oxidized with NalO^, the excess NaI04 is reduced with propylene glycol, and the formic acid for- med is measured by iodometric titration.
Hartman, L.
1956. Methanolysis of triglycerides. Journal of the American Oil Chemists
# Society, 33: 129, 1956. Chemical Ab- stracts, 50:68131 (1956).
Methyl esters were prepared by using sodium methoxide with ignited potassium carbonate as catalyst. This method was found to set free 90-95% of the total glycer- ol and cause the least degree of saponifica- tion of the various catalysts tested.
Hartmann, S. and J. Glavind
1948. A new sensitive method for the chemical determination of organic 9 peroxides. Acta physiologica Scan-
dinavica, 16 (supplement 53): 32-33. The leuco base of 2, 6-dichlorophenolindo- phenol in acidified butanol is added to a xylene solution of fatty acids and the mix- ture is heated. The color developed by the reaction is measured spectrophotometri - cally and the peroxide value is calculated .
Hartmann, S. and J. Glavind
1948. A new sensitive method for the determination of peroxides of fats and
# fatty acids . Acta chemica Scandinavia, 3: 954-958.
A method is described for the determina- tion of peroxides in which dichlorodihydroxy- phenylenediamine is oxidized by heating with a xylene-acetic acid solution of the peroxid- ized fat. The dichlorophenolindophenol which is quantitatively formed is measured colori- metrically. The reaction appears to be quantitative and specific.
Haven, F. L. and L. R. Levy
1941. The occurrence and rate of turn- over of tumor sphingomyelin. Journal
^ of Biological Chemistry, 141: 417-425.
Sphingomyelin was determined as the reineckate .
Little difference in results was found whether sphingomyelin was reextracted from the residue of Bloor's extract with petropeum ether or chloroform . More sphingomyelin was extracted when an addi- tional extraction with chloroform -methanol was used than by a single alcohol -ether ex- traction. Radioactive phosphorus was used to track the sphingomyelin turnover .
Hawthorne, J. N. and G. Hiibscher
1959. Separation of glycerylphosphoryl ■^ inositol and related compounds on
# ion-exchange columns. Biochemical A Journal, 7L 195-200.
The phospholipid is hydrolyzed with NaOH and the hydrolysis products are separated by ion exchange chromatography .
Helrich, K. and W. Rieman, III
1947. Determination of acetyl number of _ fats and oils. Analytical Chemistry, 19:
• 691.
A simplification of the method of Roberts and Schuette (Industrial and Engineering Chemistry, Analytical Edition, 4: 257, 1932).
Henley, A. A.
1957. The determination of serum cho-
■ lesterol. Analyst, 82: 286-287.
A modification of the method of Zlatkis, Zak, and Boyle which avoids protein inter- ference is described. Proteins are precip- itated by adding the serum to a stable ferric chloride-acetic acid reagent, and removed by centrifuging. The color is developed on a portion of the protein-free extract by add- ing H2SO4.
Hepburn, J . S . and R . Kotlikoff
1943. Comparative study of certain meth- ods for the determination of serum cho- lesterol. Review of Gastroenterology, J^: 170-171. Chemical Abstracts. 38: 58646(1944). The methods of Bloor (Journal of Biological
28
Chemistry, 24: 227, 1916), Myers and Wardell (Journal of Biological Chemistry, 36: 147, 1918), and Reinhold and Shiels (American Journal of Clinical Pathology, 6: 22, 1936) were studied. Results from the Bloor and Reinhold and Shiels methods agreed more closely than the Bloor and Myers and Wardell methods .
Herb, S . F . and R . W . Riemenschneider
1952. Influence of alkali concentration and other factors on the conjugation of natural polyunsaturated acids as deter - ^ mined by ultraviolet absorption measure-
ments. Journal of the American Oil Chemists Society, 29: 456-461. Chem- ical Abstracts, 47:888e (1953). Optimum conditions for maximum conjuga- tion of methyl arachidonate were found to be 15 minutes heating at 180°C in 21% KOH- glycerol. Other acids treated accordingly provided greater sensitivity in the spectro- photometric method.
Journal of Laboratory and Clinical
Medicine, 32: 1163-1168. Cholesterol esters and cholesterol are separated by adsorption on alumina and elution with 10% ethyl ether in petroleum ether and 10% ethanol in petroleum ether, respectively. The esters are saponified, and cholesterol is determined in both frac- tions by the Liebermann-Burchard method.
Hill, U. T.
1946. Colorimetric determination of fatty acids and esters. Industrial and 0 Engineering Chemistry, Analytical
Edition, 18: 317-319. A method is described for determination of fatty acids and esters by conversion to their hydroxamic acid derivatives and col- orimetric measurement of the color pro- duced with Fe"*"*"*". The fatty acids are methylated before treatment. Accuracy of the determinations was within + 0.01 mg. of cottonseed oil.
Herb, S . F . and R . W . Riemenschneider
1953. Spectrophotometric micromethod for determining polyunsaturated fatty 9 acids. Analytical Chemistry, 25: 953-
955. A method is described for determination of fatty acids with 2-5 double bonds in a 1-10 mg. sample of fat. The acids are isomerized, and the density of a methanolic solution of the isomerized acids is measured spectrophotometrically. Results by the method agree with macromethods.
Herbain, M.
1959. Estimation of blood cholesterol by colorimetry, with the use of blood coagulant. Process improvements, particularly in the case of high hyper- lipemias . Bulletin de la Societe de chimle biologique, 41: 821.-833 . Chem- ical Abstracts, 53:22188e (1959). Several modifications of the Sperry and
Webb method for cholesterol determination
are proposed.
Hess, W. C.
"^ 1947. Chromatographic separation of cho-
" lesterol and cholesterol esters in blood.
Hill, U. T.
1947. Colorimetric determination of ^ fatty acids and esters. Analytical
Chemistry, J^: 932-933. A modification of Hill's method (Indus - trial and Engineering Chemistry, Analytical Edition, 18: 317, 1946) which gives a more stable color.
Hirsch, J. and E. H. Ahrens, Jr.
1958. The separation of complex lipide mixtures by the use of silicic acid chro- -^ matography . Journal of Biological Chem-
istry, 233: 311-320. Complex lipid mixtures are separated into chemical classes by elution from a single silicic acid column. Synthetic mixtures and plasma lipids were used to test the method.
Hodgson -Jones, I. S. and V. R. Wheatley
1952. Studies of sebum. 3. Methods for the collection and estimation of small amounts of sebum . Biochemical Jour- nal, 52: 460-464. Various methods of collection and estima- tion of sebum are discussed. Carbon tetra- chloride was found to be more suitable than ether, ethanol, or acetone for removal of
29
sebum from t±e skin. Gravimetry, nephelo- metry, and chromate oxidation were found to be suitable methods for estimation of the sebum collected.
Holasek, A. andK. Winsauer
1954. Separation of saturated fatty acids by paper chromatography. Monatshefte,
* 85:796-801. Chemical Abstracts, 49:
• 2757a (1955).
C4-C18 saturated fatty acids were sepa- rated on a potassium alum -impregnated filter paper using CCl4-MeOH-conc. NH4OH (81:18:1) as developer. They were located by spraying with Rhodamine B in HCl and viewing under LTV light .
Holman, R. T. andG. O. Burr
1948. Alkali conjugation of the unsatu- ^ rated fatty acids . Archives of Biochem-
• istry, 29: 474-482.
A study of the effects of KOH concentra - tion and time of reaction on conjugation of polyunsaturated fatty acids .
Holman, R . T . and L . Hagdahl
1950. Displacement analysis of lipides.
III. Separation of normal saturated ■^ fatty acids from formic to behenic .
# Journal of Biological Chemistry, 182: 421-427.
The fatty acids were adsorbed on a Darco G-60 column and separated by displacement analysis using water, alcohol-water mix- tures, and chloroform -alcohol as solvents. Yields were not studied.
Holman, R. T.
1951. Displacement analysis of lipids.
IV. Carrier displacement separation -^ of saturated fatty acids . Journal of the
# American Chemical Society, 73: 1261- 1263.
The saturated fatty acids are separated by carrier displacement on charcoal using their methyl esters as carriers. 5-15 mg. quantities of lauric, myristic, palmitic, and stearic acids are nearly 100% recover- able.
Holman, R. T.
"At 1951. Displacement analysis of lipids .
V. Separation cf substances analogous to fatty acids . Journal of the American Chemical Society, 73: 3337-3340. Various aliphatic compounds were stud- ied for use as carriers for displacement separations. A series of C,g compounds of varying adsorbability which are suitable for use as displacers is given.
Holman, R. T. and W. T. Williams
1951. Displacement analysis of lipids. i^ VI. Separation of unsaturated acids.
^ Journal of the American Chemical So-
• ciety, 73: 5285-5289. Unsaturated fatty acids were separated
by displacement chromatography on char- coal . Saturated and unsaturated acids of 4-18 C with the same chain length were sep- arated. Effects of conjugation on adsorption characteristics are discussed.
Holman, R. T.
1951. Displacement analysis of lipids. 4_ VII. Carrier separation of unsaturated
^ fatty acids . Journal of the American
• Chemical Society, 73:5289-5292.
A method for separation of unsaturated fatty acids on charcoal using methyl esters as carriers is described. Effects of unsatu- ratlon on adsorbability are discussed.
Holman, R. T., H. Hayes, and P. R. Edmondson
1957. Analysis of unsaturated fatty acids. Essential Fatty Acids. Proceedings of the International Conference on Biochem -
• ical Problems of Lipids, 4th Oxford, (Pub. 1958) pp. 9-15. Chemical Abstracts, 53:17277f (1959).
Methods are given for analysis of unsatu- rated fatty acids by alkali isomerization (Hol- man, in Methods of Biochemical Analysis, (D. Click, Ed.) 4: 99, 1957) paper chroma - tography (Mangold, et al. Journal of the Amer- ican Chemical Society, ~77: 6070, 1956), and near-infra-red spectrophotometry (Holman and Edmondson, Analytical Chemistry, 28: 1533, 1956).
Horecker, B. L., T. S. Ma, andE. Haas
1940. Note on the determination of micro quantities of organic phosphorus.
30
Journal of Biological Chemistry, 136:
775-776. A modified Fiske-Subbarow method (Jour- nal of Biological Chemistry, 66: 375, 1925) which will determine Ijdg. of phosphorus with an accuracy of + 3% is described. A sulfuric acid concentration of 2 N is used in place of the original 0.5 N, and the color Is developed with heat.
Hornstein, I., J. A. Alford, L. E. Elliot, and P. F. Crowe
1960. Determination of free fatty acids
-^ in fat. Analytical Chemistry, 32: 540-
• 542.
Free fatty acids are separated from fat mixtures by adsorption on Amberlite IRA- 400 resin. Fat is removed by washing the resin with petroleum ether . The fatty acids are converted to their methyl esters by treatment, while on the resin, with metha- nolic HCl and are separated and identified by gas chromatography on a polyvinyl ace- tate column.
Horowitz, N. H. and G. W. Beadle
1943. A microbiological method for the determination of choline by use of a mutant of neurospora. Journal of Bio- logical Chemistry, 150: 325-333. A simple, sensitive (0.02 mg. choline/ liter), and specific method. Interfering sub- stances are removed from the solution by adsorption on Permutlt, and choline is eluted with 5% NaCl. Choline is determined by microbiological assay using a choline - less strain of Neurospora crassa .
Howard, G. A. and A. J. P. Martin
1950. The separation of the C12-C18 . fatty acids by reversed phase partition
^ chromatography. Biochemical Journal,
• 46: 532-538,
A method is given for the separation of the fatty acids on a dichlorodimethylsilane- impregnated silicic acid column.
Huennekens, F. M., D. J. Hanahan, and M. Uziel ^^ 1954. Paper chromatography of lecithins.
Journal of Biological Chemistry, 206: ^ 443-447.
A series of compounds derived from (dipalmitoleyl)-L- a-glycerylphosphoryl- choline are separated by paper chromatog- raphy, using alcohol -water mixtures as solvent systems.
Hunter, M. O., R. A. Knouff, and J. B. Brown
1945. The microdetermination of tissue lipids . Ohio Journal of Science, 45:
• 47-54. Chemical Abstracts, 39: 3804^ (1945).
Methods are described for the extraction and saponification of tissue lipids and titri- metric estimation of 1-10 mg. of fatty acids to within 2%. Other methods are also dis- cussed.
It was found that liver and adrenal tissue lipids were completely extracted by a 5 hour extraction with 3:1 alcohol -ether at room temperature. The precipitation of choles- terol as the digitonide by the Schoenheimer- Sperry method was found to be incomplete for samples of 0. 1 to 0.5 mg.
Dceda, R. M., A. D. Webb, andR. E. Kepner 1954. Chromatographic separation of j^ p-phenylazophenacyl esters on silicic
^ acid. Analytical Chemistry, 26: 1228-
• 1229.
A method is described for the separation of fatty acids by chromatography as their p-phenylazophenacyl esters on silicic acid using benzene and Skellysolve B mixtures as developing solvents.
Inouye, Y. and J. Yukawa
1940. Separation and identification of aliphatic acids. I. Hydroxamic acids , derived from saturated aliphatic acids.
"*^ Journal of the Agricultural Chemical
• Society of Japan, 16: 504-509. Chemical Abstracts, 35^:730"9(1941).
Hydroxamic acid derivatives were prepared from ethyl esters of fatty acids by reaction with hydroxylamine hydrochloride and sodium ethylate at room temperature . Data on the melting points of the derivatives are given.
Inouye, Y . and M . Noda ■A" 1950. Separation and identification of
• fatty acids. IX. Paper partition chro-
31
matography of hydroxamic acids . Journal of the Agricultural Chemical Society of Japan 18: 294-298. (English summary) Chemical Abstracts, 45: 8449f (1951). Hydroxamic acid derivatives of C2-C22 saturated aliphatic acids were chromato- graphed on paper using BuOH, EtOAc, and butrone as solvents, and located with FeCl3 in EtOH.
Rj values and colors de-
veloped with FeCl3 for the spots of 13 of the hydroxamic acids are given.
Inouye, Y. andM. Noda
1951 . Separation and identification of fatty acids . X . Simplified methods of the preparation of hydroxamic acid solutions for paper partition chroma - tography. Journal of the Agricultural Chemical Society of Japan, 24: 291-295. Chemical Abstracts, 46:6408a (1952). Four simplified methods for preparing solutions of hydroxamic acids for chromato- graphic separation are given .
Inouye, Y . and M . Noda
1951. Separation and identification of fatty acids. XI. Paper partition chro- matography of aliphatic carboxylic ■^ acids by means of hydroxamic acid
^ method. Journal of the Agricultural
Chemical Society of Japan, ^: 295-298. Chemical Abstracts, 46:6408c (1952). A modification of the Inouye and Noda method for saturated fatty acids (Journal of the Agricultural Chemical Society of Japan, 18: 294, 1950) for use with unsaturated, hydroxy, and polybasic acids. R, values using BuOH solvent, and color with FeCl3 of the hydroxamic acids derived from vari- ous acids are given.
Inouye, Y. andM. Noda
1951 . Separation and identification of fatty acids . xn . Application of paper chromatography to the analysis of fats . ^ Journal of the Agricultural Chemical
• Society of Japan, ^: 161-165. Chem-
ical Abstracts, 46:6408c (1952). The acidic oxidation products of KMnO . oxidation of a glyceride mixture are ester- ified, and the esters are converted to their
hydroxamic acid derivatives which are sep- arated by paper chromatography.
Inouye, Y., M. Noda, andY. Hamuro
1952. Separation and identification of fatty acids. XIII. Investigation of the constitution of unsaturated fatty acids ■^ by paper chromatography . Journal of
9 the Agricultural Chemical Society of
Japan, 25: 491-495. Chemical Abstracts, 46:6408T(1952). Hydroxamic acid derivatives of unsaturated fatty acids are prepared by oxidizing ozono- lysis products of the acids with alkaline AgO, esterifying the acids formed, and convert- ing the esters to their hydroxamic acid de- rivatives.
Inouye, Y. andM. Noda
1952. Separation and identification of
fatty acids . XIV . Paper chromatography of fatty acids using the filter paper im- ■^ pregnated with silicic acid. Journal of
0 the Agricultural Chemical Society of
Japan, 25: 496-499. Chemical Abstracts, 46:6408T(1952). Higher fatty acids were separated on filter paper treated with silicic acid using a butan- ol-benzene solvent mixture.
Inouye, Y. andM. Noda
1952 . Separation and identification of fatty acids . XV . Paper chromatography
_. of saturated higher fatty acids. Journal
^ of the Agricultural Chemical Society of
• Japan, 26: 634-638. (Pub. 1953) Chem-
ical Abstracts, 47:9635e (1953). Higher fatty acids were separated from mixtures of fatty acids by chromatography on petroleum hydrocarbon impregnated paper with a polar mobile phase. Rf values of the acids are given.
Inouye, Y. andM. Noda
1953 . Separation and identification of fatty acids. XVI. Paper chromatography of unsaturated higher fatty acids. Jour-
^ nal of the Agricultural Chemical Society
^ of Japan, 27: 50-53. Chemical Abstracts,
47:9635g(1953). The method of Inouye and Noda (Journal of the Agricultural Chemical Society of Japan,
32
26: 634, 1952) for saturated fatty acids was applied to unsaturated fatty acids. R^ val- ues for 14 unsaturated fatty acids are given.
Inouye, Y . and M . Noda
1955. Separation and identification of fatty acids. XVII. Paper chromatog- raphy of saturated fatty acids as their •if 2, 4-dinitrophenylhydrazides. Bulletin
0 of the Agricultural Chemical Society of
Japan, j^: 214-219 (In English). Chem- ical Abstracts, 50: 17478b (1956). 2, 4-dinitrophenylhydrazides were obtained by reaction of fatty acid chlorides with 10%, solution of 2,4-dinitrophenylhydrazine in pyridine. The hydrazides were chromato- graphed on tetralin -impregnated paper using tetralin-AcOH-EtOH or MeOH mixtures as mobile phase . The spots were located by spraying with 0.5 N KOH in EtOH. Data on melting points of the hydrazine derivatives and their R^ values with the various solvents are given.
Inouye, Y., M. Noda, and O. Hirayama
1955. Paper chromatography of unsatu- rated fatty acid esters as their mercuric
■ acetate addition compounds . Journal of
the American Oil Chemists Society, 3J:
• 132-135. Chemical Abstracts, 49:6783f (1955).
Methyl esters of unsaturated fatty acids were chromatographed as their mercuric acetate addition compounds and were detec- ted by treatment with diphenylcarbazone . Rj values of 19 of the addition compounds are given.
Inouye, Y., O. Hirayama, andM. Noda
1956. Separation and identification of fatty acids. XVni. Paper chromatog-
. raphy of fatty acids as their acetol
^ ester derivatives. Journal of Japan Oil
* Chemists' Society, _5: 16-18. Chem- ical Abstracts, 50:17478e (1956).
Acetol esters were obtained by reaction of K soaps of the fatty acids with BrCH2COCH3 and converted to z, 4-dinitro- phenylhydrazones and thiosemicarbazones. The derivatives were chromatographed on Decalin -impregnated paper with mixtures of MeOH, Decalin, AcOH, and EtOH as sol-
vents. Melting points of acetol esters and Rj values of the derivatives are given.
Inouye, Y., O. Hirayama, andM. Noda
1956. Separation and identification of fatty acids. XX. 2, 4-dinitrophenyl- hydrazones of p-bromophenacyl esters as derivatives for characterization of
# unsaturated fatty acids . Bulletin of the Agricultural Chemical Society of Japan, 20: 194-199. Chemical Abstracts, Sh 7297f (1957).
A method is described for the preparation of the p-bromophenacyl ester-2, 4-dinitro- phenylhydrazone derivatives of the C2-C20 fatty acids with even -numbered carbon chains for use as identifying derivatives for the un- saturated fatty acids .
Inouye, Y., O. Hirayama, andM. Noda
1956. Separation and identification of fatty acids. XXI. Paper chromatog- raphy of fatty acids as their p-bromo-
■^ phenacyl ester derivatives. Bulletin of
# the Agricultural Chemical Society of Japan, 20:200-205. Chemical Abstracts, 51:7297g(1957).
A method is described for the separation of fatty acids by paper chromatography as their p-bromophenacyl ester-2, 4-dinitro- phenylhydrazone derivatives and their mer- curic acetate addition compounds .
Inouye, Y., O. Hirayama, andM. Noda
1957. Separation and identification of fatty acids. XXII. Quantitative analysis
j^ of fatty acids by paper chromatography.
^ Journal of the Agricultural Chemical
# Society of Japan, 31_: 568-572. Chemical Abstracts, 53: 2084 If (1959).
The p-bromophenacyl ester-2, 4-diiutro- phenylhydrazones and Hg(0Ac)2 derivatives of the fatty acids were separated by paper chromatography, extracted with benzene, and measured spectrophotometrically.
Ireland, J.T.
1941. The colorimetric estimation of
total cholesterol in whole blood, serum, ■ plasma, and other biological material .
Biochemical Journal, 35: 283-293. The effects of ligjit, reagent concentra-
33
tions, and time and temperature of color development in the determination of cho- lesterol by the Liebermann-Burchard re- action were studied and are discussed.
A method is described for development of color using acetic anhydride -sulfuric acid (20:1), and developing at 18° for 60 minutes in the dark .
Iwayama, Y.
1959 . New colorimetric determination of _ higher fatty acids . Yakugaku Zasshi,
* 79: 552-554. (English summary).
A method is described for determination of saturated and unsaturated fatty acids from C^o ^° '-'22 ^V colorimetric measure- ment of the blue color produced by a chloro- form solution of the copper salt of the fatty acid in the presence of triethanolamine . The color follows the Lambert -Beer Law within the concentration range used, and the meth- od has good reproducibility.
Jackson, F. L. and J. E. Callen
1951. Evaluation of the Twitchell
isooleic method: comparison with the infrared trans-isoOleic method. Jour-
# nal of the American Oil Chemists Soci- ety, 28: 61-65. Chemical Abstracts, 45736'T9d(1951).
Tlie infrared method was found to be better in general than the Twitchell method.
Jacobi, H. P., C. A. Baumann, and W.J. Meek 1941 . The choline content of rats on
various choline -free diets. Journal of Biological Chemistry, 138: 571-582. Choline was determined as the reineckate. The ammonium reineckate was added in a methanol solution rather than water (Beattie, Biochemical Journal, 30: 1554, 1936), as it is more soluble in methanol, and precipita- tion was found to be just as complete.
Results by the use of the Reineckate meth- od were found to be in agreement with those by the biological assay method of Best, et al (Biochemical Journal, 29: 2278, 1935).
Jaky, M.
1959 . Paper chromatography of fats . if Fette, Seifen, Anstrichmittel, 61: 6-10.
• Chemical Abstracts, 53:12709h (1959).
Mono-, di-, and triglycerides were sep- arated by paper chromatography using 80% dimethyl ketone in water as solvent. The separated spots were identified by spraying with Rhodamine B.
James, A. T. and J. P. W. Webb
1957. ITie behavior of polyunsaturated fatty acids on the gas-liquid chromato- gram . Essential fatty acids. Proceed- ■^ ings of the International Conference on
9 Biochemical Problems of Lipids, 4th Ox-
ford, (Pub. 1958) pp. 3-8. Chemical
Abstracts, 53: 17277d (1959) . Unsaturated fatty acids were separated by chromatography on Apiezon M, and the in- dividual acids were oxidized with permanga- nate in glacial acetic acid. The resulting acids were extracted, converted to their methyl esters with diazomethane, and sep- arated and identified by rechromatography .
James, A. T.
1958. The separation of the long chain ^^ fatty acids by gas -liquid chromatography.
^ American Journal of Clinical Nutrition,
• 6: 595-600.
A discussion of factors (positional isomers, polarity of phases, etc.) which influence the separation of long-chain fatty acids by gas chromatography. A description of an ioniza- tion detector and column heater are given.
Johnson, R. M. and P. H. Dutch
1951 . Use of trichloracetic acid in puri- fication of lipids . Proceedings of the -^ Society for Experimental Biology and
Medicine, 78: 662-664. Acid-soluble material was removed from tissue with 10% TCA containing 0 . 4 M MgCl2, and lipid was then extracted with EtOH -pe- troleum ether. No measurable hydrolysis of lipids occurred.
Jones, B. J. and F. B. Moreland
1955. p-Toluenesulfonic acid, cholesterol
determination, and explosions. Clinical
■
Chemistry, I: 345.
Explosions which were apparently due to p -toluene sulfonic acid occurred during de- termination of cholesterol by the method of Pearson, Stern, and McGavack (Analytical
34
Chemistry, 25: 813, 1953).
and used as eluent.
Jones, K. K.
1950. A micromethod for fat analysis based on formation of monolayer films. ^ Quarterly Bulletin of Northwestern
* University Medical School, 24:253-256.
Chemical Abstracts, 45:5754a (1951). A method is described for estimation of lipids by spreading them in monomolecular films on an acidified water solution and measuring the area of the films.
Kaufmann, H. P. and W. Wolf
1943. Adsorption separation in the field of fats. V. The separation of cis-trans ic isomers. Fette und Seifen, 50: 519-
• 521. Chemical Abstracts, 39r205^
(1945). A comparative study and discussion of the use of AI2O3, Si02, and charcoal as adsorb- ents for the separation of isomeric fatty acids.
Jorgensen, K. and H. Dam
1957. An ultramicro method for the determination of total cholesterol in bile based on the Tschugaeff color re- action . Acta chemica Scandinavia, 1 1 : 1201-120"8^ A method is described for measurement of as little as 2^g. of cholesterol in a final volume of reaction mixture of 0.5 ml. Hy- drolysis, extraction and color development are all carried out in the same tube. The developed color is read spectrophotometric- ally.
Kabara, J. J.
1954. The light insensitivity of the
Liebermann-Burchard reaction during spectrophotometric determination of cholesterol. Journal of Laboratory and Clinical Medicine, 44: 246-249. It was found that exclusion of light during development of color with the Liebermann- Burchard reaction was unnecessary unless light of 340-540 m/. was used for measure- ment. Light had no effect on the L-B reac- tion from 580-740 m u . in either polar or nonpolar solvents.
Kapitel, W.
1956. Quantitative column chromatograph- A ic separation of mixtures of fatty acids .
^ Fette, Seifen, Anstrichmittel, 58: 91-94.
• Chemical Abstracts, 50:9761c (1956).
The C5-C23 saturated fatty acids were separated by chromatography on a column of kieselguhr which was impregnated with par- affin and treated with dichlorodimethyl si- lane. A mixture of various amounts of water and acetone was saturated with paraffin oil
Kaufmann, H. P. and J. Budwig
1950. The foam test in paper chromatog- _ raphy. Fette und Seifen, 52: 555-556.
Chemical Abstracts, 45:2236d (1951) . As little as 10// g. of oleic acid is detect- able by using an adaptation of the foam test for chromatography. The fatty acid or soap is placed on a copper acetate-impregnated paper and a H2O2-NH4OH reagent is added, causing it to foam .
Kaufmann, H. P.
1950 . New methods of fat analysis . Fette und Seifen, 52: 713-721. Chem-
• ical Abstracts, 45:8271a (1951). Various methods suitable for identification
of traces of fats and fatty acids on paper chro- matogramsare described.
Kaufmann, H . P . and J . Budwig
1951. Paper chromatography in the fat field, rv. Radiometry of oleic acid.
• Fette und Seifen, 53: 69-73. Chemical Abstracts, 45:9893e (1951).
Fatty acid is determined by formation of Co"^ soaps and radiation counting.
Kaufmann, H. P. and J. Budwig
1951. Paper chromatography in the fat field. V. Radiometric determination of the iodine number. Fette und Seifen, 53:
• 253-259. Chemical Abstracts, 45:78017 (1951).
An adaptation of the Hanus method for io- dine number determination for use in paper chromatography. The iodine number is de- termined by measurement of the radiation from the I^-^^ added by the fat.
35
Kaufmann, H. P. and J. Budwig
1951. Paper jhromatography in the field of fats. VII. Identification and separa-
_ tion of fatty acids . Fette und Seifen, 53:
* 390-399. Chemical Abstracts, 46:6851b (1952).
E)yes and metallic soaps suitable for use in locating and identifying fatty acids are discussed.
Kaufmann, H. P. and J. Budwig
1952. Biology of fats . V. Paper chroma- tography of blood lipides, the cancer
-^ problem, and fat research . Fette und
% Seifen, 54: 156-165. Chemical Abstracts
46:8703b (1952). A method is described for paper chroma- tographic separation of the lipids in a small sample of blood drawn from the finger or ear.
Kaufmann, H. P. and J. Budwig
1952 . Paper chromatography in the field of fats. X. Flourescent dyes as indica- tors in the paper chromatographic anal-
# ysis of fat acids and fats. Fette und Seifen, 54: 7-10. Chemical Abstracts, 46:7793d (1952).
Various flourescent indicators suitable for identification of fatty acids on. paper chromatogram s are given.
Kaufmann, H. P., J. Budwig, and C. W. Schmidt
1952 . Paper chromatography in the field of fats. XI. Identification and separa- ■^ tion of conjugated unsaturated fat acids.
# Fette und Seifen, 54: 10-12. Chemical Abstracts, 46:7793g (1952).
Colors obtained with various metallic soaps were used for the identification of conjugated fatty acids after chromatography on paper .
Kaufmann, H . P . and W . H . Nitsch
1954. Paper chromatography in the fat field. XVI. Further experiments on it the separation of fatty acids. Fette
# und Seifen Anstrichmittel, 56: 154-158. Chemical Abstracts, 49:14345d (1955).
Ettrections are given for separation of fatty acids from capric to stearic by paper
chromatography. High-boiling hydrocarbons and acetic acid were used as solvent phases.
Kaufmann, H. P. and H. G. Kohlmeyer
1955. Paper chromatography of waxes . I. Separation of wax alcohols. Fette, ic Seifen, Anstrichmittel, 57: 231-235.
Chemical Abstracts, 49:12859c (1955). Cio'Cjg even-numbered saturated normal alcohols can be separated from lipid mix- tures by paper chromatography using 85% acetic acid as mobile phase .
Kaufmann, H. P. andW. H. Nitsch
1955. Paper chromatography in the fat field. XVII. Separation of unsaturated ■^ fatty acids . Fette, Seifen, Anstrich-
# mittel, 57: 473-474. Chemical Ab-
stracts, 50:2190h(1956). The method of Kaufmann and Nitsch (Fette und Seifen Anstrichmittel, 56: 154, 1954) was used for the separation of unsaturated fatty acids.
Kaufmann, H. P. andW. H. Nitsch
1956. Paper chromatography in the fat field. XVIII. Separation of hydroxy- lated and brominated fatty acids . ^ Fette, Seifen, Anstrichmittel, 58: 234-
• 238. Chemical Abstracts, 50:13475b
(1956). An application of the method of Kaufmann and Nitsch (Fette, Seifen, Anstrichmittel, 57: 473, 1955) to the separation of hydroxylated and brominated acids .
Kaufmann, H. P.
1956. Paper chromatography in the fat field. XDC. Quantitative paper chro- matographic determination of the straight- chain fatty acids and their mixtures. Fette, Seifen, Anstrichmittel, 58: 492- 498. Chemical Abstracts, 52:4211h (1958). Various methods suitable for location of
fatty acids are discussed.
Kaufmann, H. P. and E. Mohr
1958. Paper chromatography of fatty . acids. XXrV. Fette, Seifen, Anstrich-
^ mittel, 60:165-177. Chemical Abstracts,
• 52:14196ir(1958).
36
A method is described for the separa- tion of fatty acid mixtures on undecane- impregnated paper .
Kaufmann, H. P. andM. M. Deshpande
1958. Paper chromatography of fats. XXVI. The quantitative paper chroma - , tographic-polarographic analysis of
^ fatty acids. Fette, Seifen, Anstrich-
mittel, 60: 537-541. Chemical Ab- stracts, 53:1783g(1959). The paper chromatographic and polaro- graphic methods for separation and deter- mination of fatty acids are compared and discussed.
Kaufmann, H. P. andM. Arens
1958. Paper chromatography of fatty acids. XX Vin. Separation of thio- -^ cyanogen derivatives. Fette, Seifen,
Anstrichmittel, 60: 803-806. Chem-
ical Abstracts, 53:3737g (1959). "Critical pairs" of fatty acids may be sep- arated by paper chromatography as their thiocyanogen derivatives using 70% acetic acid as solvent.
Kaufmann, H. P. and H. Schnurbusch
1958. The paper chromatography of fats, XXIX. Analysis of fatty acids by means
-^ of copper and mercury method. Fette,
# Seifen, Anstrichmittel, 60: 1046-1050. Chemical Abstracts, 53:8663h (1959).
A method for identification of fatty acids in a mixture by paper chromatography and conversion to their Cu and Hg soaps is de- scribed.
Kaufmann, H. P. and H. Schnurbusch
1959. Paper chromatography in the fat field. XXX. Paper chromatographic
"At analysis of the glycerides. Fette,
• Seifen, Anstrichmittel, 61^: 523-528. Chemical Abstracts, 54:5129a (1960).
Glycerides are separated on paper im- pregnated with silicone oil using acetone - acetonitrile as solvent. The spots on the devQjoped chromatogram are located by coloring with copper acetate and potassium ferrocyanide after saponification.
Kaufmann, H. P. and Z. Makus
1959. Paper chromatography in the fat field. XXXI. Separation of mixtures _, of synthetic and natural triglycerides
^ by paper chromatography. Fette, Seifen,
^ Anstrichmittel, 61: 631-636. Chemical
Abstracts, 54:5 r29b( 1960). Mixtures of triglycerides were separated on paper treated with undecane by using ace- tic acid as solvent.
Kaufmann, H. P. and H. Kirschnek
1959. Paper chromatography in the fat
field. XXXIV. Fatty aldehydes . 5. Qual- itative and quantitative analysis of fatty . aldehydes with the help of paper chroma -
tography. Fette, Seifen, Anstrichmittel, 6J.: 750-759. Chemical Abstracts, 54: 5129c (1960). Fatty aldehydes were separated as their 2, 4-dinitrophenylhydrazones by using un- decane and nitromethane as solvents for re- versed-phase paper chromatography.
Kaye, I. A.
1940. Determination of total and free cholesterol in blood serum . Journal of ■ Laboratory and Clinical Medicine, 25:
996-1001. ~
A method is described for determination of cholesterol in blood serum by precipita- tion with" digitonin directly on the lipid ex- tract and colorimetric measurement by the Liebermann-Burchard method. Saponifica- tion is unnecessary as the concentration of ester cholesterol in serum is constant. Ace- tic anhydride is used as solvent for the cho- lesterol standard as it gives a more stable solution than chloroform .
Sobel (Journal of Biological Chemistry, 157: 255, 1945) found the method in agree- ment with the Schoenheimer-Sperry method.
Kean, E. L. and F. C. Charalampous
1959. New methods for the quantitative estimation of myo-inositol. Biochimica et Biophysica Acta, 36: 1-3. Methods are described for estimation of inositol by enzymic conversion of the inosit- ol to glucuronic acid and colorimetric meas- urement by the orcinol reaction, and by spectrophotometric measurement of the
37
change in absorption caused by enzymic oxidation of triphosphopyridine nucleotide in the presence of glucuronate .
Kennedy, E. P. andH. A. Barker
1951. Paper chromatography of volatile ■^ acids. Analytical Chemistry, 23: 1033- • 1034.
A method is described for chromatography on paper of ammonium salts of the volatile fatty acids using solvents containing free am- monia for development. Bromophenol blue is used to locate the spots after development.
Kenny, A. P.
1952. The determination of cholesterol by the Liebermann-Burchard reaction. Biochemical Journal, 52: 611-619.
A modification of the L-B method for es- timation of total cholesterol in serum or plasma. The yellow component is measured at 430 mfi. The method is suitable for rou- tine clinical work. The factors influencing color development in the determination of cholesterol by the L-B reaction were studied and are discussed.
Kepner, R. E., A. D. Webb, R. L. King, and A. D. Bond
1957. p-Phenylazophenacyl esters.
Rates of movement relative to p-phenyl- j azophenacyl bromide on silicic acid and
^ identification by paper partition chroma -
tography. Analytical Chemistry, 29: 1162-1164. An improved method for the preparation of p-phenylazophenacyl bromides and a meth- od for paper chromatography of p-phenylazo- phenacyl esters are described. Rates of travel of the p-phenylazophenacyl derivatives on siUcic acid as compared to phenylazo- phenacyl bromide are given. Melting points of 30 derivatives are listed.
Kerr, L. M. H. and W. S. Bauld
1953. The chromatographic separation of "A" free and combined plasma cholesterol. ■ Biochemical Journal, 55: 872-875.
Acetone -ethanol extracts of plasma were chromatographed on alumina using petrole- um ether and benzene as eluting solvents for the separation of cholesterol and cholesterol
esters. Both the cholesterol and the esters were estimated by the Liebermann-Burchard color reaction, using separate standard curves for the cholesterol and the esters. Accuracy of the method is lower than the Schoenheimer-Sperry method.
Ketchum, D.
1946. Semimicrodetermination of sapon- ification equivalent by Rieman's double - indicator method. Industrial and Engi- neering Chemistry, Analytical Edition, 18: 273-274. A semimicro modification of Rieman's method (Industrial and Engineering Chemis- try, Analytical Edition, 15: 325, 1943).
Kibrick, A. C, T. Roberts, andS. Skupp 1951. Determination of cholesterol in blood plasma or serum by hydrolysis with benzyltrimethylammonium hydrox- ide. Archives of Biochemistry and Bio- physics, 32: 9-13. The cholesterol esters are hydrolyzed with benzyltrimethylammonium hydroxide during evaporation of the alcohol-ether tissue ex- tract. The color is developed in the residue by the Liebermann-Burchard reaction and read colorimetrically. Recovery of 89-104% of added cholesterol was obtained. The meth - od compares favorably with the Schoenheimer- Sperry method.
Kibrick, A. C, L. B. Safier, andS. J. Skupp 1959. Existence of fatty acid peroxides in normal blood and tissues of man and
# animals. Proceedings of the Society for Experimental Biology and Medicine, 101: 137-139.
The thiobarbituric reaction (Kohn and Liver sedge. Journal of Pharmacology and Experimental Therapeutics, 82: 292, 1944) was modified for determination of fatty acid peroxides in blood as well as in tissues.
Kibrick, A. C. andS. J. Skupp
1959. Chromatographic separation of , fatty acids based on chlorophenacyl
^ esters. Analytical Chemistry, 31:
* 2057-2060. ~
A method is described for synthesis of 4'-bromo-2-chloroacetophenone and prep-
38
aration of its fatty acid esters. The fatty acid esters are separated on a polyethylene column using various water-alcohol mix- tures as eluents. Melting points, solubil- ities, and absorptivities of the derivatives are given.
A drawing of a reservoir system for maintaining constant pressure while changing solvents is included.
King, E. J.
1932. The colorimetric determination of phosphorus. Biochemical Journal, 26: ^ 292-297.
Perchloric acid is used for oxidation of organic matter. l:2:4-aminonaphtholsul- fonic acid is used as a reducing agent to de- velop molybdate color.
Kingsley, G . R . and R . R . Schaffert
1949. Determination of free and total cholesterol by direct chloroform ex- A traction. Journal of Biological Chemis-
try, 180: 315-328. Cholesterol is extracted from 0.2 ml. of serum with chloroform . The extract is dried with anhydrous magnesium sulfate. Acetic anhydride and sulfuric acid are added to a portion of the dried extract and the col- or is read photometrically.
Kinley, L.
1958. Serum cholesterol determinations as affected by vitamin A. Proceedings -A of the Society for Experimental Biology
and Medicine, 99: 244-245. Very high vitamin A levels will increase the cholesterol levels as measured by the Zak method due to interference with the fer- ric chloride reagent. Moderate levels have little effect. Cholesterol values determined by the Schoenheimer-Sperry method were not affected by vitamin A.
Kirchner, J. G., A. N. Prater, and A.J. Haagen-Smit
1946. Separation of acids by chromato- graphic adsorption of their p -phenyl - ■^ phenacyl esters. Industrial and Engi-
0 neering Chemistry, Analytical Edition,
18: 31-32. A method is described for the separation
of fatty acids by chromatography of their p-phenylphenacyl esters on silicic acid. Good separations were obtained.
Kirk, E., I. H. Page, and D. D. Van Slyke
1934. Gasometric microdetermination of # lipids in plasma, blood cells, and tissue.
A Journal of Biological Chemistry, 106:
■ 203-234.
After alcohol-ether (3:1) extraction, ali- quots of the extract are used for determina- tion of lipid constituents . Total lipids are estimated by determination of total non- vol- atile carbon. Cholesterol is determined by combustion of the digitonide. Phospho- lipids are estimated as phosphoric acid by precipitation as strychnine phosphomolyb- date and determination of carbon in the pre- cipitate .
The maximum temperature of 60° was found to be critical in the evaporation of the alcohol-ether extract, as reextraction with petroleum ether was incomplete if a higher evaporation temperature was used.
Acetone -MgCU precipitates all but 2 to 3% of the phospholipids, but all the precip- itated phospholipid is not soluble in moist ether.
Kirk, E.
1938. A study on Kimmelsteil's procedure for titrimetric cerebroside determina- tion, with description of an improved technique. Journal of Biological Chem- istry, ^2^: 613-621. Kimmelsteil's procedure (Biochemische Zeitschrift, 212:259, 1929) was found to give high values for cerebroside due to the presence of interfering reducing substances. A modification is presented which removes these substances by precipitation from the hydrolyzed sample with zinc hydroxide. The method is suitable for determination of 0.3 to 1.3 mg. of pure cerebroside (+4%) and gives quantitative recovery of added cerebro- side.
Kirk, E.
1938. A micro method for approximate estimation of lecithin, cephalin, ether- ▲ insoluble phosphoinositide, and cerebro-
sides in plasma, red blood cells, and
39
tissues. Journal of Biological Chemis- try, 123. 623-636. After alcohol -ether extraction of the lip- ids, the ether -insoluble phosphatide is de- termined by phosphorus analysis of the res- idue which is insoluble in moist ether. Lec- ithin is estimated by choline analysis of the moist ether extract after Ba(0H)2 hydrolysis by the method of Roman (Biochemische Zeit- schrift, 219: 218, 1930). Cephalin is cal- culated as the difference in lecithin and to- tal ether -soluble phosphatide. Cerebro- sides are estimated by Kirk's modification Qoumal of Biological Chemistry, 123: 613, 1938) of Kimmelsteil's method. The lee - ithin precipitated with acetone -MgCl2 was found to be wholly soluble in moist ether.
Klee, Leo and G , H . Benham
1950. The determination of the true io- dine numbers of oils containing conju- gated double bond systems. Journal of # the American Oil Chemists Society, 27:
130-133. Chemical Abstracts, 44: 51I9e (1950). The modified Rosenmund-Kuhnhenn pro- cedure is made suitable for determination of iodine numbers of oils with conjugated double bond systems by extending the reac- tion time to 30-120 minutes.
Klein, P. D. and E. T. Janssen
1959. The fractionation of cholesterol 1^ esters by silicic acid chromatography.
^ Journal of Biological Chemistry, 234:
1417-1420. A method is described for the separation of cholesterol esters into groups consisting of saturated, oleate, linoleate, and arachi- donate esters by chromatography on a silicic acid column.
Klenk, E. andH. Langerbeins
1941 . Distribution of neuraminic acid in the brain. (With a micromethod for the estimation of this substance in nerve tissue.) Zeitschrift fiir physiologische Chemie, 270: 185-193. Chemical Ab- stracts, 37:899 (1943). The neuraminic acid in about 30 mg. of brain tissue can be detected by the orcinol reaction. Tissue extract is heated with or-
cinol reagent, centrifuged, and the red to red-violet color obtained is read with a col- orimeter. Galactose gives a green color with the reagent, but will interfere only if in large excess.
Knight, H. B., L. P. Witnauer, J. E. Coleman, W. E. Noble, Jr., andD. Swern
1952. Dissociation temperatures of urea complexes of long chain fatty acids, es- 9 ters, and alcohols. Analytical Chemis-
try, 24: 1331-1334. Methods for the preparation of urea ad- ducts and determination of their dissocia- tion temperatures are given. The dissocia- tion temperatures of 42 compounds are giv- en, and the use of the adducts as identifying derivatives is discussed.
Kobrle, V. and R. Zahrodnik
1954. Paper partition chromatography of . higher fatty acids. Chemicke Listy, 48:
* 1189-1196. Chemical Abstracts, 48:
• 13546h (1954).
Even -numbered Cj^q-C22 and C25 fatty acids were separated by chromatography on paper impregnated with a 12% toluene solu- tion of vegetable oils. R^ values for various solvent systems and papers are given.
Koehler, A. E. andE. Hill
1949. The molecular microdistillation of cholesterol and cholesterol esters. ■ Journal of Biological Chemistry, 179:
1-10. A small molecular still for use in analysis of small amounts (up to 5 mg.) of lipids is described. It was used for the quantitative separation of cholesterol and cholesterol es- ters by distillation.
Koenig, R . A . and C . R . Johnson
1942. Colorimetric determination of phos- phorus in biological materials. Indus - ▲ trial and Engineering Chemistry, Ana-
lytical Edition, 14: 155-156. Phosphorus is precipitated as phospho- vanadiomolybdate and measured spectrophoto- metrically. Effects of variables are discus- sed.
40
Kolb, D. K. and J. B. Brown
1955. Low temperature solubilities of fatty acids in selected organic solvents. "A" Journal of the American Oil Chemists
• Society, 32: 357-361. Chemical Ab- stracts; 49:10639d(1955).
Data on the low -temperature solubilities (10° to -70°) of several purified fatty acids in various organic solvents are given. The application of the data to separation of fatty acids by low -temperature crystallization is discussed.
Korpaczy, I.
1959. Semimicro colorimetric determina- tion of the phosphorus content of lipoids. Fette, Seifen, Anstrichmittel, 61: 748- ^ 750. Chemical Abstracts, 54: 47301
(1960). A modification of the method of Thaler (Fette und Seifen 5_4^ 763, 1952). The sam- ple is ashed with MgO and the color produced with molybdate is measured colorimetrically.
Krainick, H . G . and F . Muller
1941 . Photometric microdetermination of fat acids. Mikrochemie (vereinigt mit
# Mikrochemica Acta)i 30: 7-14. Chemical
Abstracts, 37:4416° (1943). Blood or plasma is saponified and the fatty acids are freed and extracted. An al- iquot of the extract is heated with rosana- line reagent, the color developed is meas- ured, and the fatty acid concentration is es- timated from a standard curve . Suitable for determination of 0.05 - 0.5 mg. of fatty acid in biological materials such as blood.
Krewson, C. F.
1951. Refractive indices for the methyl esters of the Cj2-C28 saturated n-ali-
# phatic acids . Journal of the American Chemical Society, 73:1365.
Methyl esters of the saturated fatty acids were prepared and refractive indices of the esters were determined. The refractive indices for the even-numbered Cj2"G28 methyl esters are given.
Kruty, M., J. B. Segur, and C . S. Miner, Jr. 1954. The determination of monoglycer-
# ides and glycerol in mixtures. Journal
of the American Oil Chemists Society, 31: 466-469. Chemical Abstracts, 49: 13461 (1955). A modification of the periodic acid meth- od of Pohle and Mehlenbacher (Journal of the American Oil Chemists Society, 27: 54, 1950).
Kuemmel, D. F.
1958. Direct determination of saturated fatty acids in fats, oils, and methyl es- _ ters. Journal of the American Oil Chem-
ists Society, 35: 41-45. Chemical Ab- stracts, 52:3365g (1958) . Saturated fatty acids with a chain length of C^^ or greater are determined by methanol - ysis of the triglycerides, oxidation of the un- saturated methyl esters with KMn04, remov- al of the oxidation products by alkaline wash- ing, and direct weighing of the isolated methyl esters of the saturated fatty acids.
Kummerow, F . A . and B . F . Daubert
1950. Limitations of the periodate oxida- tion method for the determination of monoglycerides in fats and oils.
# Journal of the American Oil Chemists Society, 27: 100-102. Chemical Ab- stracts, 44:4268c (1950).
It was shown that the method of Hand- schumaker and Linteris (Journal of the Am- erican Oil Chemists Society, 24: 143, 1947) is not specific for monoglycerides in natural fats and oils.
Kushner, D. J.
1956. A spectrophotometric microdeter- niination of choline . Biochimica et Bio- physica Acta, 20: 554-555. A modification of the method of Appleton (Journal of Biological Chemistry, 205: 803, 1953).
LaBarrere, J. A., J. R..Chipault, andW. O. Lundberg
1958. Cholesteryl esters of long-chain ■^ fatty acids. Infrared spectra and sep-
# aration by paper chromatography. Ana- ■ lytical Chemistry, 30: 1466-1470.
Methods are described for the paper chro- matographic separation of the individual cho- lesteryl esters from mixtures containing both saturated and unsaturated esters.
41
10 to 20 t g. of each compound are re- quired. IData on melting points, specific rotation, and infrared and near -infrared spectra are included.
Lambert, M. and A. C. Neish
1950. Rapid method for estimation of
glycerol in fermentation solutions .
Canadian Journal of Research, 28B:
83-89. Glycerol is oxidized to formaldehyde with periodic acid, the iodate and periodate formed are reduced to iodide with sodium arsenite, and formaldehyde is determined on the oxidation mixture by the chromo- tropic acid color reaction .
Lea, C. H. and D. N. Rhodes
1953. Phospholipins. 1. Partition chro- . matography of egg-yolk phospholipins
^ on cellulose. Biochemical Journal, 54:
467-469. The authors were unable to confirm the report of Sevan, et al (Journal of the Chem- ical Society, p. 841, 1951) that ethanolamine and choline -containiQg phospholipids were separable by partition chromatography on paper or cellulose columns. However, ami- no acid contaminants of the phospholipids in ether or chloroform solution were removed by this method.
Lea, C. H. and D. N. Rhodes
1954. Phospholipids. 2. Estimation of amino nitrogen in intact phospholipids . Biochemical Journal, 56: 613-618.
A modification of the ninhydrin method of Moore and Stern (Journal of Biological Chem- istry, 176: 367, 1948) for the estimation of phosphatidylethanolamine in the presence of phosphatidylcholine. Preliminary hydrolysis of the phospholipid is unnecessary.
Lea, C. H. and D. N. Rhodes
1954. Determination of the iodine value ▲ of phospholipids . Analyst, 79: 304-305.
The Rosenmund-Kuhnhenn method was found to give results 2 to 10% low on sam- ples of pure methyl esters, and the Yasuda method gave results 4 to 14% low.
*
A
Lea, C. H., D. N. Rhodes, and R. D. StoU 1955. Phospholipids. 3. On the chro- matographic separation of glycerophos- pholipids. Biochemical Journal, 60: 353-363.
Phosphatidyl ethanolamine and phospha- tidyl choUne were prepared from egg yolk phospholipids by silicic acid chromatog- raphy using CHCl3-MeOH as eluting solvent. Their lyso -equivalents were pref)ared from venom -treated egg yolk phospholipids in a similar manner. A method and discussion of chromatography of egg yolk phospholipids on silicic acid-impregnated paper is also given.
Egg lecithin prepared by chromatography on alumina separated into lecithin and lyso- lecithin when rechromatographed on silicic acid.
Lea, C. H.
1955. Some observations on the prepara- tion and properties of phosphatidyl eth- anolamine. Proceedings of the Interna -
A tional Conference on Biochemical Prob-
lems of Lipids, 2nd Ghent. (Pub. 1956) pp. 81-90. The changes which occur during autooxida- tion of phosphatidyl-ethanolamine are dis- cussed.
Deoxygenation of the Si02 column before chromatography of phospholipids led to de- creased formation of oxidation products .
Lees, M.
1956. Simple procedure for the isolation of brain sulfatides . Federation Proceed- ings, 15: 298.
Brain white matter is v^xtracted with CHCI3- MeOH and the extract is washed according to Folch, et al (Federation Proceedings, 13: 209, 1954). The extract is purified by reextraction and the sulfatide is precipitated at -10° .
Leffler, H. H.
1959. Estimation of cholesterol in serum. American Journal of Clinical Pathology, ■ 3V. 310-313.
Iscpropyl alcohol is used for the simul- taneous precipitation of serum proteins and the extraction of total cholesterol. Free cholesterol is precipitated as the digitonide
42
from an aliquot . FeCl3 in 87% H3PO4 is used as color reagent.
Leupold, F. andH. Buttner
1953. The hydrolysis of acetals of hi^er fatty aldehydes. Zeitschrift fur physio- logische Chemie, 292: 7-13. Chemical Abstracts, 48:11366F(1954). A study was made of the hydrolysis of di- methyl acetals of palmitaldehyde and stear- aldehyde in AcOH and AcOH-2 N HCl mix- tures. The hydrolysis of the aldehydes was found to be incomplete in 99-100% AcOH, but proceeded readily in 90% AcOH. The aldehydes were determined photometrically at 293 myu . after extracting with cyclohex- ane and drying the extract with Na2S04.
Leupold, F. and D. Eberhagen
1959. A simple method for the separation of unsaturated acids from small amounts "A: oflipides. Fette, Seifen, Anstrichmit-
• tel,
60: 809-811. 53:3738d(1959).
Chemical Abstracts,
Polyunsaturated fatty acids were separated by low -temperature urea fractionation.
Levene, P. A. and I. P. Rolf
1927. The preparation and purification
"A" of lecithin. Journal of Biological Chem-
A istry, 72: 587-590.
Methods are given for the extraction and purification of lecithin from egg yolk, brain, and liver tissues. The lecithin is precipita- ted from ethanol with CdCl2 and purified by precipitation from chloroform solution with methanol -gaseous ammonia. Analyses of purified products are given.
Levine, C . and E . Chargaff
1951. Procedures for the microestima- tion of nitrogenous phosphatide constit- A uents. Journal of Biological Chemistry,
192: 465-479. Ethanolamine, serine, and choline, in a- mounts of 5-75^g., were determined as follows: The phosphatides were hydrolyzed, the fatty acids were removed, and the bases were separated by paper chromatography. Ethanolamine and serine were located on the developed chromatogram with ninhydrin and estimated by colorimetry of the eluted
spots with ninhydrin . Choline spots were converted to choline phosphomolybdate, re- duced to molybdenum blue, and the spots were measured by planimetry.
Levine, C. and E. Chargaff
1951. Chromatographic behavior of ana- logues of the nitrogenous lipide constit- uents. Journal of Biological Chemistry, 192: 481-483. Analogues of ethanolamine, serine, and choline were separated by paper chromatog- raphy using several solvent systems, and estimated by the ninhydrin reaction.
Liberti, A., G. P. Cartoni, and U. Pallotta 1958. Vapor -phase chromatography of methyl esters of fatty acids and their . quantitative determination by automatic
coulometry. AnnaU di Chimica (Rome) • 48: 40-49. Chemical Abstracts: 52:
9869e (1958). Methyl esters were separated on a sili- cone grease column using glass powder as a support and burned to CO2 at the exit. The CO2 was passed into an ethanolic solu- tion of BaCl2, Ba(0H)2, andH202- The cur- rent used to maintain constant pH of the so- lution, which is a quantitative measurement of the CO2 formed, is recorded graphically. Sensitivity of the method is 0.2 microequiv- alents, and accuracy is 2-5%.
Lieboff, S. L.
1928. A colorimetric method for the de- termination of lipoidal phosphorus in A blood. Journal of Biological Chemistry,
80: 211-214. Lipids are extracted with alcohol -ether, the solvent is evaporated, and organic mat- ter is oxidized with H2SO4 and H2O2. Phos- phorus is precipitated as uranium phosphate, dissolved in trichloracetic acid, converted to uranium ferrocyanide, and the ferrocya- nide is measured colorimetrically.
Lipmann, F . and L . C . Tuttle
1945. A specific micromethod for the determination of acyl phosphates. Jour- nal of Biological Chemistry, 159: 21-28. Acyl phosphates are determined by conver- sion to hydroxamic acid derivatives and
43
measurement of the color produced by the ferric hydroxamate complex.
Lips, H.J.
1953. Observations on the determination of iodine value with pyridine sulfate di- bromide. Journal of the American Oil Chemists Society, 30: 399-403. Chem- ical Abstracts, 47: 12843b (1953). A study of the effects of variables (reac- tion time, reagent concentration, catalyst, solvent, peroxides, and sulfur) on iodine values determined by the pyridine sulfate dibromide method of Benham and Klee (Jour- nal of the American Oil Chemists Society, 27: 127-130, 1950).
Lipsky, S. R. andR. A. Landowne
1959. Evaluation of a stationary phase for fatty acid analysis by gas -liquid ■if chromatography. Annals of the New
# York Academy of S.:iences, 72 (arti-
cle 13): 666-674. The saturated and unsaturated fatty acids of chain length C]^2'*-'26 were quickly sepa- rated on a diethylene glycol -succinate poly- ester column by gas chromatography.
Lipsky, S.R., R. A. Landowne, and J. E. Lovelock
1959. Separation of lipides by gas -liquid . chromatography. Analytical Chemistry,
* 3J.: 852-856.
A method is described for separation of methyl esters of fatty acids to C22 by gas- liquid chromatography on a capillary column coated with Apiezon L, using an argon de- tector . The minimum amount of organic vapor detectable by the method is approxi- mately 10"^^ mole.
Long, C. and D. A. Staples
1959. Determination of neuraminic acid in crude brain lipids. Biochemical Jour- nal, 73: 385-389. Brain tissue lipids were extracted with CHCl3-MeOH (2:1) and partitioned according to Folch, et al (Journal of Biological Chem- istry, 226: 497, 1957). The neuraminic acid content of the aqueous methanol phase was determined by measuring the extinction value of the orcinol reaction products before
•
▲
and after treatment of the sample with acid. A discussion of the method is given.
Lovern, J. A.
1950. Estimation of choline as the
reineckate. Chemistry and Industry,
A p. 707. Chemical Abstracts, 45:34481(1951).
The method of Marenzi and Cardial (Jour- nal of Biological Chemistry, 147: 363, 1943) for the oxidative determination of choline reineckate will give more stable results if the acetone is evaporated from the reineckate precipitate prior to oxidation.
Lovern, J. A.
1952. The application of counter -current distribution to the separation of phos- pholipins . Biochemical Journal, 51^: 464-470.
In an aqueous ethanol -petroleum ether system, the separation of phosphatidyl- choline from ethanolamine and serine phos- pholipids was fair, but separation of phos- phatidyl ethanolamine from phosphatidyl serine was poor .
Lovern, J, A. and J. OUey
1953. The lipids of fish. 2. The acetone- , soluble lipids in the flesh of the haddock.
Biochemical Journal, 54: 128-137. The acetone -soluble lipids are fractionated by precipitation with acetone at 0° from an ether or chloroform solution . The soluble portions were fractionated further by counter- current distribution between petroleum ether and 85% ethanol.
Lovern, J . A . and J . OUey
1953. The lipids of fish. 4. The lipids extracted by an ethanoLether mixture from haddock flesh previously extracted with acetone . Biochemical Journal, 55: 686-696. An ethanol-ether (3:1) extract of haddock flesh which had been extracted previously with acetone was reextracted with petroleum ether. The petroleum ether extract was washed and the component lipids were frac- tionated by counter -current distribution be- tween petroleum ether and 85% ethanol .
44
Lovem, J. A.
1956. The lipids of fish. 8. The tri- i^ glycerides and cholesterol esters of
J[ haddock flesh. Biochemical Journal,
• 63: 373-380.
The acetone extract of haddock flesh, con- taining the cholesterol esters and triglycer- ides, was chromatographed on silicic acid with petroleum ether, petroleum ether - benzene, and benzene -ether as eluting sol- vents . Fair separation of the hydrocarbons, cholesterol esters, and triglycerides was achieved.
Luecke, R. W. and P. B. Pearson
1944. The determination of free choline in animal tissues. Journal of Biological Chemistry, 155: 507-512. Lecithin is removed by precipitation with acetone. Free choline is then separated by adsorption on Etecalso and elution with 5% NaCl, and assayed with a cholineless strain Neurospora crassa.
The method gave results in agreement with relneckate precipitation method for the to- tal choline in liver, but chemical methods were not sensitive enough for determination of free choline .
Lynn, W. S., Jr., L. A. Steele, and E. Staple 1956. S^Jaration of 2, 4-dinitrophenyl- hydrazones of aldehydes and ketones -ff by paper chromatography . Analytical
Chemistry, 28: 132-133. The 2, 4-dinitrophenylhy(lrazones were separated by chromatography on phenoxy- ethanol -impregnated paper using heptane as mobile phase .
MacGee, J.
1959. Enzymatic determination of poly - ^ unsaturated fatty acids . Analytical
• Chemistry, _31: 298-302.
A method is described for the determina- ticMi of total polyunsaturated fatty acids by oxidation of the potassium salts of the fatty acids with atmospheric oxygen in the pres- ence of lipidoxidase, and spectrophotomet- ric measurement of the conjugated product.
(Essentially the same as MacGee, et al. Essential Fatty Acids. Proceedings of the International Conference on Biochemical
Problems of Lipids, 4th Oxford, (Pub. 1958) pp. 21-29.)
1957,
McKibbin, J, M. and W. E. Taylor
1949. The nitrogenous constituents of the tissue lipids. I. The extraction, purification, and hydrolysis of tissue "^ lipids . Journal of Biological Chemistry,
178: 17-27. Tissue was extracted with ethanol-ether (3:1), followed by a six-hour continuous ex- traction with chloroform. Non-lipid im- purities were removed by emulsification of a chloroform extract with a 0.25 M MgCl2, freezing to break the emulsion, and removal of the MgCl2 solution. A five-hour Ba(0H)2 iiydrolysis was used to free combined cho- line.
McKibbin, J. M. and W. E. Taylor
1949. The nitrogenous constituents of the tissue lipids. II. The determina- tion of sphingosine intissue lipid ex- tracts . Journal of Biological Chemis- try, 178: 29-35. The lipid extract was hydrolyzed with saturated Ba(0H)2 and refluxed with HCl, and the liberated sphingosine was extracted with CHClg . The sphingosine was then di- gested for N according to Koch and McMeekin (Journal of the American Chemical Society, 46: 2066,' 1924) and determined colorimet- rically .
The extraction method is claimed to be quantitative and specific in the presence of other lipid bases. The method was used routinely for a range of 6 to 20 umoles of sphingosine,
McKibbin, J. M.
1959. Determination of inositol, ethanol- amine, and serine in lipides. Methods of Biochemical Analysis, D. GUck, editor. New York, Interscience Pub. Inc., Vol. 7, pp. 111-143. Methods are described for determination of lipid inositol by bioassay with Saccharo- myces carlsbergensis, and colorimetric de- termination of ethanolamine and serine with sodium 1, 2 -naphthoquinone -4 -sulfonate aft- er sealed-tube hydrolysis with 4 N HCl and separation on Permutit.
45
Various other methods for determination of inositol, ethanolamine, and serine are discussed.
A discussion of factors affecting the de- velopment of maximum color in the Lieber- mann-Burchard reaction.
MacLachlan, P. L.
1944. Determination of the iodine niim- ber of whole phospholipid. Journal of Biological Chemistry, 152: 97-102. When chloroform was used to dissolve phospholipid which had been precipitated with acetone and MgCl2 (Yasuda, Journal of Biological Chemistry, ^: 410, 1931-32) the iodine numbers of the phospholipid were erratic. Reliable iodine numbers were obtained when the chloroform solu- tion of phospholipid was evaporated to dry- ness and the phospholipid redissolved in chloroform. Reliable iodine numbers were also obtained when chloroform -ether (1:1) or moist ether were used as solvents, but neither was as good a solvent for the phos- pholipid as chloroform. It is suggested that the erratic values with the original chloroform solution are due to the forma- tion of a phospholipid-MgCl2 complex which is partially soluble in chloroform .
Mac Lean, H.
1914. A simple method for the prepara- ^ tion of lecithin . Journal of Pathology
A and Bacteriology, 18: 490-494.
Lecithin was prepared by a series of precipitations with acetone from an alcohol - water emulsion.
Ma, T. S. and J. D. McKinley
1953. Determination of phosphorus in organic compounds: A new mtcropro- cedure. Mikrochimica Acta, 1 : 4-13 (In English). Chemical Abstracts, 47: 9858a (1953). A method is described for determination of organic phosphorus using the yellow phos- phovanadomolybdate color in place of molyb- denum blue.
Machebouef, M . A . and J . L . Delsal
1942. Colorimetric determination of small quantities of free or esterified _ cholesterol. Bulletin de la Societe de
chimie biologique, 24: 296-309. Chem- ical Abstracts, 40:103^(1946).
Mai, S. H.
1951. Ultramicromethod for separation and determination of fatty acids on nylon "^ thread. Federation Proceedings, 10:
• 388.
A method is described for the Reparation of straight-chain, even numbered, saturated fatty acids from Cg to C^g by chromatog- raphy on nylon thread. The acids are sep- arated into groups, and the individual mem- bers of the groups are separated by use of various solvent mixtures for development. The separated acids are estimated by the monolayer film method. Suitable for deter- mination of 2-6 jug. of each acid in a mix- ture of the acids.
Makita, T.
1958. Stability for oxidation of unsaturated fatty acids in their urea adduct crystals. Review of Physical Chemistry of Japan,
* 28:31-35. (In EngUsh). Chemical Ab- stracts, 53:14546b (1959).
The urea adduct of unsaturated fatty acids becomes unstable with oxidation in air at 80°, but stabilizes at higher pressures and pro- tects the acid from oxidation by air .
Mallov, S., J. M. McKibbin, andj. S. Robb 1953. The distribution of some of the essential lipides in beef heart muscle and conducting tissue . Journal of Bio- logical Chemistry, 201: 825-837. Modifications of the anthrone colorimet- ric carbohydrate procedure for use in lipid sugar determination are given. The meth- od was found to be more satisfactory than other reduction and colorimetric procedures . Attempts to apply the selective hydrolysis and reineckate precipitation methods for sphingomyelin to beef heart lipid extracts were unsuccessful. The Brand-Sperry (Jour- nal of Biological Chemistry, 141: 545, 1941) sugar reduction method and the Bruckner (Zeitschrift fiir physiologische Chemie, 286: 163, 1941) orcinol sugar color method were found to be unsatisfactory for beef heart lipid sugar determination.
46
Man, E. B. and E. F. Gildea
1932. A modification of the Stoddard and Drury tltrimetrlc method for the deter- minatlon of the fatty acids in blood
* serum . Journal of Biological Chemistry,
99: 43-60. The alcohol -ether extract of serum is saponified, and the fatty acids are freed with HCl and titrated with NaOH.
Bloor's extraction procedure gave incom- plete extraction.
Man, E. B. and J. P. Peters
1933. Gravimetric determination of serum cholesterol adapted to the Man and Gildea fatty acid method, with a note on the estimation of lipoid phosphorus. Journal of Biological Chem- istry, 101: 685-695.
A micro modification of the digitonin pre- cipitation method which utilizes the solution left from the Man and Gildea (Journal of Bio- logical Chemistry, 99: 43, 1932) fatty acid determination. Phospholipid is determined by the Fiske-Subbarow method on an aliquot of the same solution .
Man, E . B .
1937. A note on the stability and quanti-
tative determination of phosphatides.
Journal of Biological Chemistry, 117:
183-187. Phosphatide decomposition occurs during the evaporation in air of solvents from solu- tions of phospholipids . Evaporation under N2 at low pressure and temperature avoids the decomposition.
Man, E. B. and E. F, Gildea
1937. Notes on extraction and saponifica- tion of lipids from blood and blood " serum . Jouraal of Biological Chemistry,
122: 77-88. No significant difference was found in the use of NaOH or KOH for saponification, con- trary to earlier findings .
Refluxing of blood with alcohol -ether for 1 hour gave greater yield of lipid phosphorus than heating for 1 to 5 minutes, and higher yields were also obtained when the reflux- ing was carried out in an inert atmosphere .
Mangold, H. K., B. G. Lamp, and H. Schlenk 1955. Indicators for the p^-^er chroma- ^ tography of lipids . Journal of the Amer-
lean Chemical Society, 77: 6070-6072. Indicators are described for the detection of various lipids on paper chromatograms .
Marcali, K. andW. Rieman, in
1946. Microdetermination of the sapon- ification number of fats and oils. In- dustrial and Engineering Chemistry, Analytical Edition, 18: 144-145. A description of methods for determina- tion of the saponification number of fats and oils using samples of about 500, 50 and 15 mg.
Marenzi, A. D. andC. E. Cardini
1943 . Colorimetric micromethod for determining total and unsaturated fat acids of blood. Revista de la Sociedad • Argentina de Biologia, 19: 118-130.
Chemical Abstracts, 38: 563^ (1944). Blood lipids are extracted and the fatty acids are converted to Pb soaps . The Pb is then precipitated from the soaps as PbCrO^ and the Cr is determined.
Marenzi, A. D. andC. E. Cardini
1943. The colorimetric determination of choline • Journal of Biological Chemistry, 147: 363-370.
Seattle's method (Biochemical Journal, 30: 1554, 1936) was modified as follows: 1) 60% acetone in water was used to dissolve the reineckate, eliminating the problems of evaporation caused by use of acetone alone . Lower concentrations of acetone did not dis- solve the salt completely, or else gave rise to a precipitate on standing. 2) The choline reineckate was precipitated by a 20 minute immersion in ice water, as precipitation was found to be complete under those condi- tions.
A new method for the determination of choline was proposed, based on the precip- itation of choline as the reineckate and col- orimetric determination of the chromium in the precipitate, which is sensitive to 15 yuLg. of choline. See also: Lovern, Chemis- try and Industry, 707, 1950.
47
Marenzi, A. D. andC. E. Cardini
1943. On the determination of the phos- pholipids in blood. Journal of Biolog- ical Chemistry, 147: 371-378 . Total lipid phosphorus was determined by the Fiske-Subbarow method, sphingo- myelin by determination of the phosphorus content of its reineckate, and choline by determination of the chromium content of its reineckate. Satisfactory results were not obtained by colorimetric measurement of sphingomyelin reineckate.
Marinetti, G. V. andE. Stotz
1955. Paper chromatographic separation •^ of phospholipids. Journal of the Amer- A ican Chemical Society, 77: 6668-6670.
Phosphatidylethanolamine and acetal phos- pholipid were acylated with acetic anhydride, benzoyl chloride, or 2, 4-dinitroflouroben- zene and separated by chromatography on paper with solvent mixtures containing lutidine, acetic acid, and methanol or oc- tanol .
Marinetti, G. V. and E. Stotz
1956. Chromatography of phosphatides on silicic acid impregnated paper. Biochimica et Biophysica Acta, 21: 168-170.
Phosphatides were separated on silicic acid-impregnated paper using diisobutyl ketone -acetic acid-water (40:30:7) or n-butyl ether -acetic acid-chloroform - water (40:35:6:5) as solvents.
Marinetti, G. V., J. Erbland, and J. Kochen
1957. Quantitative chromatography of ■^ phosphatides . Federation Proceedings, A 16: 837-844.
Methods are described for the separation of phosphatides on silicic acid -impregnated paper and silicic acid columns. EWisobutyl ketone -acetic acid-water and diisobutyl ketone -n-butyl ether -acetic acid-water, in various ratios, are used as developing sol- vents .
Washing the silicic acid with methanol- chloroform before use gave more repro- ducible results than activation by heating, (cf . Kay and Trueblood, Analytical Chem- istry, 26: 1566, 1954).
•
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•
▲
Marinetti, G. V., J. Erbland, andE. Stotz
1959. The quantitative analysis of plas-
malogens by paper chromatography.
Biochimica et Biophysica Acta, 31:
251-252.
Lecithin and phosphatidylethanolamine are isolated by silicic acid chromatography and hydrolyzed with acetic acid. The re- sulting lysophosphatides are separated by paper chromatography. The plasmalogen content of the original lipid is calculated from the amount of lipid phosphorus in the lysolecithin or lysophosphatidylethanol- amine.
Marinetti, G. V., M. Albrecht, T. Ford, and E. Stotz
1959. Analysis of human plasma phos- phatldes by paper chromatography. Biochimica et Biophysica Acta, 36: ^ 4-13.
Plasma lipids were extracted and chro- matographed on silicic acid-impregnated paper using diisobutyl ketone-acetic acid- water (40:25:5) as solvent. The phospha- tide spots were extracted with methanolic HCl and digested with perchloric acid and phosphorus was determined by spectro- photometric measurement of the phospho- molybdate .
Marquardt, P. andG. Vogg
1952. A sensitive assay of choline and acetylcholine by means of sodium tetraphenylboron . Zeitschrift fur physiologische Chemie, 291: 143-147. Chemical Abstracts, 48: 12855e (1954). Choline or acetylcholine is precipitated quantitatively by tetraphenylboron in acid solution. Data on infrared absorption spec- tra and solubilities of the complexes are given.
Mata, M.
1948. Simplified determination of blood lipides . Re vista Farmaceutica de Cuba, ■ 26: 29-31. Chemical Abstracts, 43:
38711 (1949). The sample of blood is dried on filter pa- per. The lipids are extracted with Et20- EtOH(5:l), dried, and weighed. Choles- terol is extracted from the residue with
48
CHCI3 and determined by the Liebermann- Burchard reaction .
Matthews, F. W., G. G. Warren, and J. H. Michell
1950. Derivatives of fatty acids. Ana-
# lytical Chemistry, 22: 514-519.
X-ray diffraction powder patterns of sil- ver salts, amides, and anilides of fatty acids were studied and found to be suitable for fatty acid identification . Methods for preparation of the derivatives and data on their X-ray diffraction are given.
Mead, J. F.
1957. The metabolism of the essential fatty acids. VI. Distribution of un-
. saturated fatty acids in rats on fat -free
supplemented diets . Journal of Biolog- ical Chemistry, 227: 1025-1034. Unsaturated fatty acids were chromato- graphed on siliconized Celite, hydrogenated, and rechromatographed. Acids with differ- ing degrees of unsaturation were well sepa- rated.
Meredith, P. andH. G. Sammons
1952. Horizontal paper chromatography.
if Analyst, 77: 416-418-
A method for horizontal paper chroma- tography is described. The method was used to separate the water-soluble constit- uents of a methanolic-HCl hydrolysate of nerve lipids .
Meredith, P. andH. G. Sammons
1959. A reaction between meso-inositol and uranyl acetate. Analyst, 83: 686. Inositol can be detected on paper chroma - tograms by its flourescence when sprayed with uranyl acetate.
Michaels, G. D., G. Fukayama, H. P. Chin, and P. Wheeler
1958. Technics for separation of plasma cholesterol esters for determination of
-if iodine value, and of cholesterol. Pro-
■ ceedings of the Society for Experimental
Biology and Medicine, 98: 826-829. Cholesterol esters are separated from blood lipids by chromatography on silicic acid. Iodine number is determined by a
colorimetric modification of Yasuda's method. Cholesterol is determined by a modification of the Schoenheimer-Sperry method using an orcinol -ferric chloride color reagent.
Michaels, G. D.
1958 . A note on increasing the accuracy of the micro alkaline isomerization _ technic for determination of unsaturated
fatty acids . American Journal of Clin- ical Nutrition, 6: 593-594. Absorption due to reagent blank in the method of Herb and Riemenschneider (Ana- lytical Chemistry, 25: 953, 1953) is reduced by acidification of the isomerized fatty acids, extraction of the fatty acids with petroleum ether, evaporation of the extract to dryness, and dissolving the fatty acid residue in methanol for spectrophotometric reading.
Michaels, G. D., P. Wheeler, G. Fukayama, and H . P . Chin
1958. Column chromatographic fractiona- ^ tion of plasma lipids; American Jour-
• nal of Clinical Nutrition, 6: 604-605. A method is described for separation of
cholesterol esters, free cholesterol, and mono-, di-, and triglycerides from blood plasma lipids by chromatography on silicic acid using petroleum ether and diethyl ether in varying concentrations as eluents. Re- covery of added glycerides is quantitative.
Michaels, G. D., P. Wheeler, G. Fukayama, and L. W^ Kinsell
1959. Plasma cholesterol fatty acids in human subjects as determined by alka- line isomerization and by gas chroma-
# tography . Annals of the New York Academy of Sciences, 72 (art. 13): 633-640.
Cholesterol was determined by a modifica- tion of the Schoenheimer and Sperry method using orcinol for color development.
A procedure is described for determina- tion of unsaturated fatty acids in amounts of approximately 0.3 mg. by a modification (Michaels, American Journal of Clinical Nutrition, 6: 593, 1958) of the spectrophoto- metric method of Herb and Riemenschneider (Analytical Chemistry, 25: 953, 1953).
49
The microisomerization method of Hoi- man (in Methods of Biochemical Analysis, D. Click, Editor, 1957, vol. 4, p. 99) was found to give errors as hig^ as 50%, presumably due to the high blank.
Michalec, C.
1957. The nature of cholesteryl esters in the higher fatty acids in human blood
j^ serum. Essential fatty acids. Proceed-
^ ings of the International Conference on
* Biochemical Problems of Lipids, 4th ■ Oxford, (Pub. 1958) pp. 105-110.
Chemical Abstracts, 53: 17278h (1959). Cholesterol and cholesteryl esters were separated from blood lipid extracts by chro- matography on paraffin oil -impregnated paper using aaAcOH-CHCU -paraffin oil (65:25:10) mobile phase. Higher fatty acids were separated by using 93-95% AcOH as mobile phase. "Critical pairs" were sepa- rated by KMn04 oxidation of the unsaturated fatty acids prior to chromatography.
Michalec, C .
1958. Two-dimensional paper chroma- . tography of hi^er fatty acids . Bio- _ chimica et Biophysica Acta, 28: 212-
• 213. ~~ Fatty acids were separated by two- dimensional chromatography on paraffin oil -impregnated paper. The first chroma - togram was run at 20° using 93% acetic acid, and the second chromatogram was run at -8° using formic acid-acetic acid- water as solvent.
Molines, J. and P. Desnuelle
1948. Colorimetric determination of
phosphorus in oils and lecithins.
Bulletin mensuel d'information ITERG,
No. 2: pp 1 -3 . Chemical Abstracts',
42:4493d (1948). The sample is digested with HNO3 and H2SO4 and phosphorus is determined col- orimetrically, using metol as reducing agent for molybdic acid. As little as 0.01 mg. of phosphorus can be determined by this method.
Monasterio, G. and G. Gigli
1947. A new method for the study of the
lipides of feces. Rassegna de fisio- patologica clinica e terapeutica (Pisa), 29: No. 11/12, 33 pp. Chemical Ab- stracts, 43:2658e (1949). Lipids are extracted from feces with ace- tone and ether. Directions are given for the determination of the individual lipids .
Moretti, J. and J. Polonovski
1954 . Chromatographic separation of bromine derivatives of stearic acid. ■^ Bulletin. Societe chimique de France,
• pp. 935-936. Chemical Abstracts, 48: 13544a (1954).
Bromo derivatives of stearic acid are separated by chromatography on paper or a cellulose or Cellte column, and the com- pounds are eluted according to their solu- bilities in petroleum ether, ethyl ether, dichloroethylene and trichloroethylene .
Morgan, D. M. and K.J. Kingsbury
1959. A modified hydroxamic acid meth- _ od for determining total esterified fatty
acids in plasma . Analyst, 84:409-414. The esterified fatty acids in plasma were converted to their hydroxamates and the col- ored complex formed with ferric chloride was measured at 515 m^. Variation + 0.85%. Recoveries from glyceryl trioleate = 99.7%.
Moyle, v., E. Baldwin, andR. Scarisbrick 1949. Separation and estimation of sat- urated C2-Cg fatty acids by buffered ^ partition columns. Biochemical Jour-
• nal, 43 : 308-317.
The fatty acids are separated on a heavily buffered silica gel column with butanol- water mixtures as elutlng solvents. The separated acids are estimated by titration. Effects of variables and applications of the method are discussed.
Mukerjee, H.
1959. Paper chromatography of volatile if fatty acids. Analytical Chemistry, 31:
• 1284. ~ MeOH-NH3 and MeOH-acetone-NH3 sol- vent mixtures are used to separate the am- monium salts of formic, acetic, propionic, and butyric acids by paper chromatography .
50
Munier, R.
1951. Partition microchromatography on paper of alkaloids and various bio- logical nitrogenous bases. V. Separa- tion of the nitrogenous constituents of
■^ the phosphoaminolipides; choline, eth-
▲ anolamine and serine . Bulletin de la Societe de chimie biologique, 33: 862- 867. Chemical Abstracts, 46: 4172a (1952).
Good separation on paper was obtained by using BuOH-ethylene chlorohydrin coned. NH4OH-H2O (50:10:5:16), or BuOH saturated with H2O and acidified with AcOH, as the mobile phase.
Nakamura, G. R.
1952. Microdetermination of phosphorus.
▲ Analytical Chemistry, 24: 1372.
A micro modification of King's method (Biochemical Journal, 26: 292, 1932) for determination of l-lO/'g. of phosphorus.
Narayan, K. A. andB. S. Kulkarni
1954. Urea complexes of fatty acids. II. Effect of solvent dilution on com- plex formation. Journal of Scientific # and Industrial Research (India) (B) 13^
9-15. Chemical Abstracts, 49: 5861h (1955). The effects of H2O dilution, urea concen- tration, and other variables on the forma- tion of urea complexes of fatty acids are discussed.
Nelson, G. J. andN. K. Freeman
1959. Serum phosphoUpide analysis by . chromatography and infrared spectro-
v^ photometry. Journal of Biological
Chemistry, 234: 1375-1380. A semimicro method is described in which the extracted lipids are separated by elution from a silicic acid-Celite col- umn with methylene chloride, acetone, 35% methanol in methylene chloride, and meth- anol . The amounts of cephaUn, lecithin, and sphingomyelin are determined by infra- red spectrophotometry. Error of the meth- od is approximately 10%, depending on the sample .
Ng, H., A. D. Webb, and R. E. Kepner
1956. Use of 2, 4-dinitrophenylhydra- _. zones of p-phenylphenacyl esters as
^ second derivatives of organic acids.
• Analytical Chemistry, 28: 1975-1977. A method is described for the separation
and identification of the fatty acids from acetic to octadecanoic by chromatography as their p-phenylphenacyl -2, 4-dinitro- phenylhydrazone derivatives on a silicic acid-nitromethane column. Nitromethane - saturated Skellysolve B is used as eluting solvent.
Nicolet, B . H . and L . A . Shinn
1941. The determination of serine by
the use of periodate. Journal of Biolog-
^ ical Chemistry, 139: 687-692.
TTie formaldehyde formed from serine by the action of periodate as determined as the dimedon derivative. Accuracy of 2-3% was achieved with amino acid samples con- taining about 20 mg. of serine. The method is not suitable for use in the presence of carbohydrates or hydroxylysine, as they react with periodic acid to yield formalde- hyde.
Niermierko, W.
1947. Micromethods for the determina- tion of iodine and thiocyanogen numbers _ of fatty acids . Acta biologiae experi-
• mentalis (Warsaw) 14: 199-205. Chem- ical Abstracts, 42:92041 (1948).
A modification of the method of Rosen - mund and Kuhnhenn (Zeitschrift fiir Unter- suchung der Nsihrungs- und Genussmittel, 46: 154, 1923) was used for the microdeter- mination of iodine number .
Niermierko, W .
1947. A micromethod for the determina- tion of saturated acids . Acta biologiae
• experimentalis (Warsaw) 14: 207-209. Chemical Abstracts, 42:9205b (1948).
A modification of Bertram's method (Zeit- schrift fiir Untersuchung der Lebensmittel, 55: 179, 1928) for use in microdetermina- tion of saturated acids .
51
Nobil, E., M. G. Hagney, E. J. Wilder, and F.N. Briggs
1954. Simplified method for determina- tion of total adrenal cholesterol. Pro- ■ ceedings of the Society for Experimen-
tal Biology and Medicine, 87: 48-50. An adaptation of the Zlatkis, Zak, and Boyle (Journal of Laboratory and Clinical Medicine, ^: 486, 1953) procedure for use in determination of adrenal cholesterol. It is faster and simpler than the Lieber- mann-Burchard method.
Noda, M . , O . Hirayama, and Y . Inouye
1956. Separation and identification of fatty acids. XIX. Paper -chromato- graphic analysis of component fatty if acids of natural fats . Joui-nal of the
# Agricultural Chemical Society of Japan,
30: 106-111. Chemical Abstracts, 52: 2Tl66h (1958). Unsaturated fatty acids were determined by a modified mercuric acetate addition method (Inouye, et al. Journal of the Amer- ican Oil Chemists Society, _32: 132, 1955), higher saturated fatty acids by 2, 4-dinitro- phenylhydrazide formation (Inouye and Noda, Bulletin of the Agricultural Chemical Soci- ety of Japan, 19: 214, 1955) and chromatog- raphy of their hydroxamic acids, and vola- tile fatty acids by chromatography of their hydroxamic acid derivatives.
Noda, M.
1959 . Paper chromatography of unsatu- i^ rated glycerides . Scientific Reports,
11,
Kyoto Prefectural Univ . Agr . No.
pp. 169-175. A method is described for the separation and identification of unsaturated glycerides by paper chromatography of their mercuric acetate addition compounds.
extracted with ethanol-ether (3:1), hydro- lyzed with 6 N NaOH, and determined by spectrophotometric measurement of their dinitrophenyl derivatives at 420m^ . Cho- line and inositol do not interfere, but amino acids will .
Norris, F. A. andR. J. Buswell
1944. Stability of Wijs solution for iodine number determinations. Industrial and Engineering Chemistry, Analytical Edition, 16: 417. No significant change occurred during storage of Wijs solution in brown bottles for 505 days at room temperature.
O'Brien, R. G., et al
1938. Iodine value of oils and fats.
Australian Chemical Institute Journal and Proceedings, 5:329-334. Chem- ical Abstracts, 33:420^ (1939). The Wijs (Analyst, 54: 12, 1929), Rosen - mund and Kuhnhenn (Zeitschrift f{ir Unter- suchung der Nahrungs- und Genussmittel, 46: 154, 1923), and Toms bromine vapor (Analyst 53: 69, 1928) methods were stud- ied and compared. The R & K method gave low values and required frequent restand- ardization. The Toms method is recom- mended for its speed.
Okey, R.
1930. A micro method for the estimation of cholesterol by oxidation of digitonide. ■ Journal of Biological Chemistry, 88:
367-379. An adaptation of Bloor's oxidative proce- dure for lipids (Journal of Biological Chem- istry, 77: 63, 1928) for use in the determination of cholesterol as the digitonide. See also: Yasuda, Journal of Biological Chemistry, 92: 303, 1931.
Nojima, S. and N. Utsugi
1957. Quantitative determination of lipide-ethanolamine and lipide- serine and their distribution in rat and pig ▲ tissues. Journal of Biochemistry
(Tokyo) 44: 565-573. Chemical Ab- stracts, 52: 1333b (1958). A specific and sensitive method is de- scribed for the determination of ethanol- amine and serine in lipids . The lipids are
Olley, J.
1953. Effect of solute concentrations on countercurrent distribution of phospho- lipins . Biochimica et Biophysica Acta, 10:493-498. Variation in the concentration of the orig- inal solution of phospholipids causes a change In the distribution patterns.
52
OUey, J.
1955. Quantitative paper chromatog- raphy of lipid constituents. Proceed- , ings of the International Conference on
Biochemical Problems of Lipids, 2nd Ghent. (Pub. 1956) pp. 49-55. A discussion of methods for estimation of the constituents of lipid hydrolysates by paper chromatography.
Ono, F. andY. Toyama
1943. The highly unsaturated acids in fats and oils. I. Re -examination of the sodium salt-acetone and lithium ^ salt -acetone methods for the separa-
^ tion of highly unsaturated acids of fish
* oils. Journal of the Chemical Society of Japan, 64: 1327-1331. Chemical Ab- stracts, Jl:3755a (1947).
The lithium salt-acetone method was found to be better than the sodium salt- acetone method for separation of the highly unsaturated acids of fish oils .
Ory, R. L., W. G. Bickford, and J. W. Dieckert 1959. Glass paper chromatography of , the long-chain fatty acids, brominated
^ derivatives, and methyl esters . Ana-
* lytical Chemistry, 31: 1447-1448.
A method is described for separation of long-chain fatty acids, both saturated and unsaturated. The methyl esters of the acids are brominated and chromatographed on glass paper impregnated with silicic acid. Isooctane is used as the developing solvent.
Alumina paper did not give as good results.
Page, E . and L . Michaud
1951. The titrimetric determination of _ plasma fatty acids. Canadian Journal
* of Medical Science, 29: 239-244. Plasma lipids are extracted and sapon- ified, and the fatty acids are freed with HCl and extracted. The fatty acids are then dissolved in an alcoholic solution of thymol blue and titrated with tetramethylammonium hydroxide .
Pangbom, M . C .
1941 . A note on the purification of leci- ■ic thin . Journal of Biological Chemistry, A 137:545-548.
Lecithin is precipitated with CdCl2 from an alcoholic solution, and purified by re- peated extraction from an 80% alcohol - petroleum ether solution. Sphingomyelin and plasmalogen are not removed from the lecithin .
See Pangborn, Journal of Biological Chem- istry, 188: 471, 1951, for modifications of the method.
Pangborn, M. C.
1942 . Isolation and purification of a
, serologically active phospholipid from
beef heart . Journal of Biological Chem- istry, 143: 247-256. "Cardiolipin" was extracted from beef heart with methanol and purified by recrystal- llzation of the CdCl2 salt from alcohol and ether. It was identified as- essential mate- rial for reactivity of beef heart antigens in the serological test for syphilis.
Pangbom, M . C .
1944. Acid cardiolipin and an improved method for the preparation of cardio-
^ lipin from beef heart . Journal of Bio-
logical Chemistry, 153: 343-348. Cardiolipin is extracted from the tissue with methanol (Pangborn, Journal of Biolog- ical Chemistry, 143: 247, 1942), precip- itated with BaCl2. and purified by reprecip- itation from solvent solutions with BaCl2 and CdClo- Yield of 0.6 grams was obtained from a kilogram of moist tissue .
Pangborn, M . C .
1945. A note on the preparation of cardio- lipin . Journal of Biological Chemistry, 157: 691-692.
Na2S04 is recommended for decomposition of the crude barium salts of cardiolipin in place of the NaCl previously used (Pangborn, Journal of Biological Chemistry, 153: 343, 1944). The NaCl method does not give com- plete recovery of cardiolipin in a large scale preparation.
53
Pangborn, M. C.
1945. A simplified preparation of cardio- lipin, with a note on purification of A lecithin for serologic use. Journal of
Biological Chemistry, 161: 71-82. A simplification of Pangborn (Journal of Biological Chemistry, 153: 343, 1944).
Pangborn, M. C.
1951 . A simplified purification of leci-
"A" thin . Journal of Biological Chemistry,
A JJ8: 471-476.
Lecithin is purified by repeated precip- itation from alcohol with CdClo. Lecithin with an N:P ratio of 1.01:1 is obtainable. Yield; 10.5 gm. from 12 eggs.
Paquot, C.
1947. The determination of the sapon- ification number of fats . Journal des recherches du Centre national de la # recherche scientifique (Paris) pp. 131-
135. Chemical Abstracts, 42:5689a (1948). The double bonds of unsaturated aliphatic acids may react during saponification of triglycerides with alcoholic KOH, and lead to erroneous results.
Park, J. T. andM. J. Johnson
1949. A submicro determination of glucose . Journal of Biological Chem- istry, 181: 149-151. A very sensitive method. Glucose is de- termined by reduction of ferricyanide and colorimetric measurement. Range of 1-9 /ig. of glucose in 1-3 ml. sample. The re- action is not specific for glucose. -^
Pearson, S., S. Stem, andT. H. McGavack 1953. A rapid, accurate method for the determination of total cholesterol in ■ serum. Analytical Chemistry, 25: 813-
814. ~
Glacial acetic acid, p-toluenesulfonic acid and acetic anhydride are added to 0.1 ml. of serum and allowed to cool without mixing. Con. H9SO4 is added and the solution is mixed. After 20 minutes, the optical den- sity is measured at 550 m^ . Recovery of added cholesterol and cholesterol acetate = 99.2 + 3.6%. Average variations in values
for analyses of the same serum over a 24 hour period ranged from 0.4 to 2.4%. Av- erage deviation of duplicates was less than 5%. Average deviation from values by the Schoenheimer-Sperry method + 3.5%. Equi- molar quantities of cholesterol and choles- teryl acetate give equal color densities by this method.
Perila, O.
1956. Separation of saturated straight chain fatty acids . HI. Quantitative pa - ^ per chromatography. Acta chemica
Scandinavia, 10: 143-144. Solvent systems are described for sepa- ration of the fatty acids from formic to cerotic by paper chromatography.
Peterson, M . H . and M.J. Johnson
1948. The estimation of fatty acids of
_. intermediate chain length by partition
^ chromatography. Journal of Biological
• Chemistry, 174: 775-789.
The fatty acids from formic to capric were separated on a Celite column using sulfuric acid as the stationary phase with Skellysolve B-benzene and butanol-chloro- form as mobile phases. Higher fatty acids do not interfere.
PhilUps, G. B.
1958. The isolation and quantitation of the principal phospholipid components
■A" of human serum using chromatography
▲ on silicic acid. Biochimica et Biophys-
ica Acta, _29: 594-602. A modification of the Lea, Rhodes, and Stoll chromatographic method (Biochemical Journal, 155: 19, 1944). Lecithin, sphingo- myelin, lysolecithin, and phosphatidyl etha- nolamine were isolated from human serum by chromatography on silicic acid using methanol and chloroform as eluents.
Extraction of serum with chloroform - methanol (1:1) was found to be as effective as Bloor's alcohol-ether (3:1) extraction.
Phillips, G. B. andN. S. Roome
1959. Phospholipides of human red blood , cells. Proceedings of the Society for
Experimental Biology and Medicine, 100: ^ 489-492.
54
Red blood cell phospholipids were sepa- rated into ethanolamine - and serine -con- taining phospholipids, lecithin, sphingo- myelin and lysolecithin by chromatography of silicic acid.
Pierfitte, M. and J. Barrier
1959. Microdetermination of serum cho- lesterol by a reaction with ferric chlo- ride . Bulletin de la Societe de phar- macie de Nancy, No . 40, pp. 31-39. Chemical Abstracts, 54:1648e (1960). A modification of the method of Zlatkis, et al (Journal of Laboratory and Clinical Medicine, 41: 486, 1953). The unmodified Zlatkis method gave results approximately 7% too high .
Pikaar, N. A. and J. Nijhof
1958. Microdetermination of the fatty ^ acids in blood serum . Biochemical
* Journal, 70: 52-57.
The lipids in 2 ml. of serum are extrac- ted with ethanol-ether (3:1) and saponified. The fatty acids are isomerized with KOH in ethylene glycol, and the amounts of each of the polyethenoid fatty acids are calcu- lated from the difference in optical densi- ties at various wave lengths before and after the isomerization.
Saturated fatty acids are determined by a modification of the method of van de Kamer (Biochemical Journal, 61: 180, 1955).
The method compares well with the meth- od of Herb and Riemenschneider (Analytical Chemistry, 25: 953, 1953) .
Pippen, E . L . , E.J. Eyring, and M . Nonaka 1957. Chromatographic separation of . 2, 4-dinitrophenylhydrazones. Analyt-
ical Chemistry, 29: 1305-1307. Methods for the preparation and chroma- tography on silicic acid-celite of the 2, 4-di- nitrophenylhydrazone derivatives of aliphat- ic aldehydes and ketones are described. Data on separation of various combinations of the derivatives are given.
Piatt, B . S . and G . E . Clock
1943. The estimation of inositol in ani- mal tissues. Biochemical Journal, 37: 709-712.
The ether -soluble -70% acetone -insoluble fraction is separated from an aqueous ex- tract of tissue. Glucose is removed from the extract by yeast fermentation and acid- ic and basic substances are removed by ion-exchange resins. The free inositol is oxidized with HIO4 and the excess acid is estimated lodometrlcally .
Pohle, W. D. and V. C. Mehlenbacher
1950 . A modification of the periodic method for the determination of mono- glycerldes and free glycerol in fats and # oils. Journal of the American Oil
Chemists Society, 27: 54-56. Chemical Abstracts, 44:3272a (1950). Free glycerol and monoglycerldes are separated by extraction of the glycerol with water from a chloroform solution of the sample. Glycerol is determined on the wa- ter solution, and monoglycerldes are deter- mined in the chloroform solution by period- ic acid oxidation.
Pollak, 0. J. and B. Wadler
1952 . Rapid turbldlmetrlc assay of cho- lesterols . Journal of Laboratory and Clinical Medicine, 39: 791-794. Free or total cholesterol is assayed by nephelometric measurement of the turbidity produced by cholesterol digitonlde .
Polonovski, J., J. Etlenne, M. Paysant, and M. Petit
1959 . Chromatographic fractionation of , plasma phospholipides. Annales de blo-
2 logie cllnique (Paris) 17: 186-192.
Chemical Abstracts, 53:22181e (1959). A method is described for separation of plasma phospholipids by paper chromatog- raphy .
Popjak, G.
1943. Colorlmetrlc determination of to- tal, free, and ester cholesterol in tissue ■ extracts. Biochemical Journal, 37:
468-470. A modified combination of the Kelsey (Journal of Biological Chemistry, 127: 15, 1939) and Schoenheimer-Sperry (Journal of Biological Chemistry, 106: 745, 1934) meth- ods. Cholesterol is precipitated as the
55
digitonide and separated . The digitonlde is then decomposed and the cholesterol is determined by colorimetric measurement of the color produced with Liebermann- Burchard reagent.
Privett, O. S., E. Breault, J. B. Covell, L. N. Norcia, andW. O. Lundberg
1958. Solubilities of fatty acids and de- rivatives in acetone. Journal of the American Oil Chemists Society, 35:
• 366-370. Chemical Abstracts, 52:
15095h (1958). Solubilities of fatty acids, alcohols, tri- glycerides, and methyl esters in acetone were studied using purified materials. Data on solubility of the materials at different temperatures are given.
Quaife, M. L., R. P. Geyer, andH. R. Bolliger
1959. Rapid paper chromatographic
j^ microassay of free and ester choles-
terol of blood. Analytical Chemistry,
■ 31: 950-955.
A method is described for separation of free and ester cholesterol from blood serum by chromatograpl^ of an acetone -ethyl ether (1:1) extract on ZnC03 -impregnated filter paper. The cholesterol -containing areas are eluted with CHClo and cholesterol is determined on the eluate by a modified Zlatkis procedure. Effects of variables and possible interferences are discussed. Coefficient of variation of duplicates done on different days was 3.5%.
Radin, N. S., F. B. Lavin, and J. R. Brown 1955. Determination of cerebrosides. Journal of Biological Chemistry, 217: 789-796. Interfering ions are removed by ion-ex- change chromatography. Cerebrosides are determined by a modified anthrone proce- dure (Black, Analytical Chemistry, 23: 1792, 1951), after solution in phosphoric acid. Average recovery is 99.7% and standard deviation is 1.9%.
Radin, N. S. and J. R. Brown
1955. Preparative isolation of cerebro- ■^ sides. Federation Proceedings, 14:
266. Lipids from beef spinal cord are mixed with ether and Celite and filtered. The fil- ter cake is air dried and extracted with hot alcohol. The filtrate is cooled and the re- sulting precipitate is filtered off, dissolved, and passed through a "Flourisil" column to remove the phospholipids. The eluate is dried, dissolved in chloroform -alcohol-water (8:10:1), and passed through an ion exchange resin mixture. The resulting cerebroside material assays 87% pure.
Radin, N. S.
1957. Glycolipide chromatography.
Federation Proceedings, 16: 825-826. In the method described, a mixture of brain lipids is passed through a "Flourisil" (activated magnesium silicate) column to remove phosphatides and gangliosides, after which the sulfatides are adsorbed on a mix- ture of ion exchange resins. The cerebro- sides and other non-ionic materials are then chromatographed on an unsulfated Dowex 50 column. The sulfatides may be eluted from the ion exchange column with a chloro- form-alcohol-water solution of lithium ace- tate and precipitated with BaCl2.
Ramsay, W. N. M. and C. P. Stewart
1941 . The analysis of blood phospho- A lipins. Biochemical Journal, 35: 39-47.
The amounts of lecithin, sephalin, and sphingomyelin in blood are calculated from the analysis for phosphorus, choline, glyc- erol, and ethanolamine . Choline is deter- mined as the reineckate, and glycerol as formaldehyde .
Ramsey, L.L. andW. I. Patterson
1945. Separation and identification of the volatile saturated fatty acids (C^ to -^ C4). Journal of the Association of Of-
0 ficial Agricultural Chemists, 28: 644-
656. A method is described for separation of the C1-C4 saturated fatty acids by chroma- tography on silicic acid. Tlie fatty acids are eluted with butanol -chloroform, using water as the stationary phase, and identi- fied by microscopic examination of their crystalline derivatives. n-Butyric and
56
isobutyric acids are not separated from each other. The method is capable of de- termining 1 mg. of an individual acid in a 5-10 mg. mixture of the acids.
Ramsey, L. L. andW. I. Patterson
1948. Separation and determination of the straight -chain saturated fatty acids -^ C5 to C^o ^y partition chromatography.
^ Journal of the Association of Official
Agricultural Chemists, 31: 139-150. C5 to Cio fatty acids are separated by chromatography on silicic acid, using methanol and 2,2,4-trimethylpentane as solvent phases. Isomers of the same chain length are eluted together.
Ramsey, L. L. andW. I. Patterson
1948. Separation of the saturated
straight -chain fatty acids Cn to C^g. ^ Journal of the Association of Official
* Agricultural Chemists, 31: 441-452.
The fatty acids are separated by chroma- tography on silicic acid, using furfuryl al- cohol-2 aminopyridine and n-hexane as sol- vent phases, and identified by titration with NaOH.
Rapport, M. M. and N. Alonzo
1955. Photometric determination of fatty _ acid ester groups in phospholipides.
Journal of Biological Chemistry, 217: 193-198.
Phospholipid esters are converted to hy- droxamic acids, and the color produced with acid ferric perchlorate is read" spectro- photometrically at 530 m/i . The sensitivity can be increased by decreasing the amount of ferric perchlorate added. As little as 20 jj-g. of phospholipid can be measured by the method.
Carlson and Wadstrom (Scandinavian Jour- nal of Clinical and Laboratory Investigation, 10: 407, 1958) found this methpd to be the simplest, with good accuracy and ready re- producibility. Hirsch (Journal of Biological Chemistry, 233: 213, 1958) recommends substitution of n-butanol as solvent for cho- lesterol esters, as it would circumvent the insolubility of reaction products in the etha- nollc ferric perchlorate color reagent.
Rapport, M. M. and N. Alonzo
1955. Identification of phosphatidal cho- line as the major constituent of beef ▲ heart lecithin. Journal of Biological
Chemistry, 217: 199-204. Modifications of the Schiff test and Korey and Wittenberg's p-phenylhydrazone forma- tion test (Federation Proceedings, 13: 244, 1954) are used for the identification of al- dehydes. The methods are both quantitative, and are in correspondence with each other for phosphatidal choline analysis .
Rapport, M . M . and B . Lerner
1958. A simplified preparation of sphingo- myelin . Journal of Biological Chemistry, ^ 232: 63-65.
A method is given for the preparation of pure sphingomyelin from commercial beef heart .lecithin by hydrolysis and solvent re- crystallization .
Reid, R . L . and M . Lederer "
1951 . Separation and estimation of sat- . urated C2-C7 fatty acids by paper par-
tition chromatography. Biochemical • Journal, 50: 60-67.
The acids are separated by chromatog- raphy of their amm^onium salts with a n- butanol -aqueous ammonia solvent system. The spots are located by spraying with a bromocresol purple -formaldehyde solution and the acids are estimated by measurement of spot area. Accuracy + 2 to 5%.
Rhodes, D. N. andC. H. Lea
1955. Chromatographic separation of glycerophospholipids . Proceedings of J the International Conference on Biochem-
. ical Problems of Lipids, 2nd Ghent
(Pub. 1956) pp. 73-79. The glycerophospholipids were separated on silicic acid columns or silicic acid- impregnated paper using chloroform -meth- anol mixtures as eluting solvents.
Rhodes, D. N.
1958. Interference by polyunsaturated fatty acids in the determination of cho- lesterol. Biochemical Journal, 71: 26P Highly purified fatty acid esters were found to give spurious colors in determination of
57
cholesterol by the ferric chloride method of Zlatkis, Zak, and Boyle (Journal of Lab- oratory and Clinical Medicine, 41: 486, 1953). Color yields, expressed as percent- ages of cholesterol value, varied from 0.047 to 6.5%.
method of Herb and Riemenschneider (Ana- lytical Chemistry, 25: 953, 1953) for deter- mination of the fatty acid composition of 0.5 to 2 ml. of plasma or- of the fractions from a chromatographed (Si02) sample of tissue lipids.
•
A
Rice, E. W. and D. B. Lukasiewicz
1957. Influence of bromine in the Zak cholesterol method. Clinical Chem-
" istry, 3: 160-162.
Traces of Br will give high values in the FeCl3-H2S04 color reaction for cholesterol. Shaking the serum with Agl03 before extrac- tion with ethanol-dimethyl ketone will elim- inate the Br interference.
Rice, F . A . H . and A . G . Osier
1951. Chromatographic purification and serologic studies of a beef heart leci- thin . Journal of Biological Chemistry, 189: 115-121. A method is described for the purification of lecithin for use in sero-diagnosis of syph- ilis. The lecithin is adsorbed on a "Mag- nesol" (hydrated magnesium acid silioate)- Celite column and eluted with 2% tertiary - butyl alcohol in benzene .
Riemenschneider, R. W., S. F. Herb, and P. L. Nichols, Jr.
1949. Isolation of pure natural linoleic acid and linolenic acids as their methyl j^ esters by adsorption fractionation on
^ silicic acid. Journal of the American
• Oil Chemists Society, 26: 371-374. Chemical Abstracts, 43:68391(1949).
The methyl esters were prepared from linoleic and linolenic acids from tobacco oil and linseed oil, respectively, and chro- matographed on silicic acid-Celite with pe- troleum ether and petroleum ether methyl ether.
Riemenschneider, R. W., F. E. Luddy, and S. G. Morris
1958. Determination of fatty acids in small amounts of plasma and in lipid components of tissues by ultraviolet
* spectroscopy. American Journal of CUnical Nutrition, 6: 587-591.
An adaptation of the spectrophotometric
Rigamonti, R . and V . Ricco
1954. Separation of fatty acids of differ- ent molecular weight by means of addi-
^ tion compounds with urea. Annali di
Chimica (Rome)44: 288-298. Fatty acids of 90% purity may be separa- ted from fatty acid mixtures by fractional precipitation of their urea complexes.
Rikimaru, M., Y. Tanaka, andM. Hoshino
1955. Paper chromatography of phospho- lipides. Fukushima Journal of Medical Science, 2: 131-133. Chemical Ab-
•
stracts, 50:13156d(1956). A study of solvents suitable for the paper chromatography of lecithins and lysolecithin . Best results were obtained with a butanol- glycerol -water mixture.
Rikimaru, M.
1955. Chromatographic separation of lecithin and lysolecithin on silica - ■^ treated filter paper disk. Fukushima
▲ Journal of Medical Science, 2: 175-177.
Chemical Abstracts, 50:13147g (1956). Lecithin and lysolecithin were separated on silica -impregnated filter paper using CHCl3-MeOH or CHCl3-EtOH as developing solvents. TTie bands were located with phos- phomolybdic acid. Rj values are given.
Roberts, H. R. andW. Bucek
1957. Rapid procedure for separation of C2 to C6 volatile fatty acids by hori- ■^ zontal paper chromatography at elevated
^ temperature . Analytical Chemistry,
29: 1447-1449. The C2 to C6 fatty acids were separated by horizontal paper chromatography of their ethylamine salts using butanol saturated with water as solvent and a temperature of 50° for development.
Roberts, W . L . and H . A . Schuette
1932 . Determination of hydroxyl number
58
of oils, fats and waxes . Industrial and Engineering Chemistry, Analytical Ed- ition, 4: 257-259. A method is described in which the hy- droxyl number is determined by reaction of the sample with acetic anhydride in a sealed tube, after which the excess anhy- dride is hydrolyzed and titrated.
Robins, E., O. H. Lowry, K. M. Eydt, and R. E. McCaman
1956. Microdetermination of phospho- lipides and sphingolipides in brain. A Journal of Biological Chemistry, 220:
661-675. Cephalins, lecithins, and sphingolipids were determined in 10 jJLg. of brain tissue by a modification of the method of Schmidt, et^ (Journal of Biological Chemistry, 166: 505, 1946).
Roboz, E., W. C. Hess, R. R. DiNella, and W. Cevallos
1958. Determination of total lipids, cho- # lesterol, and phospholipids in cerebro-
A spinal fluid. Journal of Laboratory and
■ Clinical Medicine, 52: 158-162.
Methods suitable for use in the determina- tion of total lipids, free and esterified cho- lesterol, and phospholipids in spinal fluid are described.
Roman, W. Ill
1930. A chemical method for the deter- mination of choline and some physico- chemical data on choline and its salts . A Biochemische Zeitschrift, 219: 218-
231. Chemical Abstracts, 24:3029 (1930). Choline is precipitated as choline per- iodide with I2, and the excess I2 is titrated with Na2S203. Determines 5^g. to 5 mg. of choline with accuracy of + 5%.
Rose, A. R., F. Schattner, andW. C. Exton 1941. A method for determining blood cholesterol. American Journal of Clin- ical Pathology, Supplement 5: 19-23. Cholesterol is extracted with alcohol - acetone (1:1) and determined colorimetri- cally with the ZnCU -acetyl chloride reac- tion (Tschugaeff, Chemiker -Zeitung, 24:
542, 1900).
Rosen, H.
1957. A modified ninhydrin colorimetric analysis for amino acids.. Archives of Biochemistry and Biophysics, 67: 10- 15. ~
A modification of the method of Yemm and Cocking (Analyst, 80: 209, 1955) which avoids the use of unstable solutions of re- duced ninhydrin.
Rosenmund, K . W . and W . Kuhnhenn
1923. A new method for the determination of the iodine number in fats and oils by the use of pyridine sulfate dibromide. Zeitschrift fur Untersuchung der Nahr- ungs- und Genussmittel, 46: 154-159. Chemical Abstracts, 18:477(1924). The sample is brominated by using pyri- dine sulfate dibromide reagent, and the ex- cess reagent is titrated iodometrically .
Rosenthal, H . L . , M . L . Pfluke, and S, Buscaglia
1957. A stable iron reagent for the de- termination of cholesterol. Journal of ■ Laboratory and Clinical Medicine, 50:
318-322. ~~
The use of phosphoric acid in place of glacial acetic acid as solvent for ferric chloride gave a more stable reagent for cho- lesterol determination. The reagent may be stored at room temperature instead of frozen, as is required by the acetic acid so- lution . The results found by using the new reagent agreed well with other methods,
Rosenthal, H. L., M. L. Pfluke, and J. Callerami
1959. The colorimetric estimation of se- _ rum fatty esters . Clinica Chimica Acta,
• ±: 329-333.
A modification of the Stern and Shapiro (Journal of Clinical Pathology,. 6: 158, 1953) hydroxamic acid procedure which uses cho- lesterol acetate as a standard in place of olive oil.
Rossi, L., A. D. Marenzi, and R. Lobo
1942. Photometric microdetermination of the chromate ion. Anales de farmacia
59
y bioqulmica (Buenos Aires) 13: 1-8.
Chemical Abstracts, 36:6442^(1942). A method for use with Reinecke precip- itates. NaOH and H2O2 are added direct- ly to a solution of the salt, the solution is acidified with H2SO4, diphenylcarbazide is added, and the solution is compared with a standard in a colorimeter.
Rouser, G., G. V. Marinetti, R. F. Witter, J . F . Berry, and E . Stotz
1956. Paper chromatography of phospho- -^ lipides. Journal of Biological Chemis-
A try, 223: 485-497.
Individual phospholipids were separated from each other and other lipids by paper chromatography using mixtures of lutidine and acetic acid with alcohols or chloroform as solvents. Factors influencing the mobil- ity of phospholipids on paper were studied and are discussed. An explanation of the chromatographic behavior of phospholipids is presented.
Rudloff, E. von
1956. Periodate -permanganate oxidations, rv . Determination of the position of double bonds in unsaturated fatty acids
# and esters . Journal of the American Oil Chemists Society, 33: 126-128. Chemical Abstracts, 50:6815b (1956).
Unsaturated fatty acids were quantitative- ly oxidized with periodate -permanganate re- agent. The oxidation products were sepa- rated by chromatography on silicic acid and identified.
Rusoff, I. I., R. T. Holman, andG. O. Burr
1945. Table of spectroscopic data on fats, fatty acids, and their esters . Oil and
• Soap, 22: 290-294. Chemical Abstracts, 40:224'^ (1946).
A table of spectroscopic data with 81 ref- erences.
Saifer, A. andO. F. Kammerer
1946. Photometric determination of total cholesterol in plasma or serum by a modified Liebermami-Burchard reaction. Journal of Biological Chemistry, 164: 657-677.
Acetic anhydride -dioxane (3:2) is used
for simultaneous extraction of cholesterol and precipitation of protein in serum or plasma. Color is developed by addition of H2 SO4 to the extract. Accuracy is j- 5%. The effects of the variables are given.
Saifer, A.
1951 . Photometric determination of total and free cholesterol and the cholesterol ester ratio of serum by a modified Lieb- ermann-Burchard reaction. American Journal of Clinical Pathology, 21^: 24-32. A modification of the total cholesterol method of Saifer and Kammerer (Journal of Biological Chemistry, 164: 657, 1946) for use in the determination of free cholesterol in serum .
Sakagami, T.
1958. A new colorimetric method for de- termination of sphingosine base in lipids. Journal of Biochemistry, (Tokyo) 45: 313-317. Chemical Abstracts, 52: 18598g(1958). Sphingosine base is oxidized with lead acetate and the fatty aldehyde formed is de- termined by measurement of the color pro- duced by the plasmal reaction.
Sakuri, H.
1954. Complexes of urea with fatty acids and their derivatives. I. Separation of fatty acids and their methyl esters by _, urea complexes, and consideration of
^ the reaction mechanism. Journal of the
Chemical Society of Japan, Industrial Chemistry Section, 57: 50-51. Chemical Abstracts, 49:2098b (1955). Stearic and oleic acid are more readily separated if urea complex methods are used on their methyl esters rather than the free acids .
Samuelson, G.
1953 . The photometric determination of choline and choline derivatives. Jour- nal of Pharmacy and Pharmacology, 5: 239-244. Choline is determined by spectrophoto- metric measurement at 415 m . of an ace- tone solution of its 2,4,6-hexanitrodiphenyl- amine derivative. The color is stable and the method is accurate to within 2%.
60
Sato, Y., G. T. Barry, and L. C. Craig
1947. Identification of small amounts of . organic compounds by distribution
_ studies. Vn. Separation and estima-
tion of normal fatty acids . Journal of Biological Chemistry, 170: 501-507. Counter-current distribution is used for the separation and quantitative estimation of the C2-C5 normal fatty acids to within 2-3%.
Schaffer, F. L., J. Feng, and P. I. Kirk
1953. Microgram and submicrogram de- termination of phosphate. Analytical ^ Chemistry, 25: 343-346.
A method is described for determination of phosphorus in quantities from 5-7 ^g. to 2m^g. The sample is digested with H2SO4 in a sealed tube, and the phosphorus is converted to phosphomolybdic acid. The phosphomolybdic acid is extracted with octyl alcohol, reduced with stannous chloride, and measured spectrophotometrically .
Octyl alcohol extracts phosphomolybdic acid, but not appreciable amounts of molyb- dic acid; an improvement over the isobutyl alcohol used by Berenblum and Chain.
Schlenk, H . and R . T . Holman
1950. Separation and stabilization of . fatty acids by urea complexes. Jour-
^ nal of the American Chemical Society,
• 72: 5001-5004.
The use of urea complexes for separation of fatty acids is described, and factors in- fluencing the separation are discussed.
Urea complexes of unsaturated fatty acids are not subject to autooxidation.
Schlenk, H., J. L. Gellerman, J. A. Tillotson, and H . K . Mangold
1957. Paper chromatography of lipides. . Journal of the American Oil Chemists
2, Society, 34: 377-386. Chemical Ab-
stracts, 51:15689c (1957). Detailed procedures are given for the qualitative and quantitative paper chroma- tography of lipids, and applications of the methods. Rf values for 16 fatty acids are given.
Schmidt, C, J. Benotti, B. Herschman, and S.J. Thannhauser
1946. A micromethod for the quantitative partition of phospholipid mixtures into •^ monoaminophosphatides and sphingo-
▲ myelin. Journal of Biological Chemis-
try, 166: 505-511. The monoaminophosphatides are removed by selective saponification with KOH, and the value of sphingomyelin phosphorus is calculated as the difference between phos- phorus values of total phospholipid and sa- ponified phospholipid.
Schmidt, G., L. Hecht, P. Fallot, L. Green- baum, andS. J. Thannhauser
1952. The amounts of glycerylphosphoryl- choline in some mammalian tissues. A Journal of Biological Chemistry, 197:
601-609. Glycerylphosphorylcholine was determined as the difference in the amount of choline reineckate obtained before and after 20 min- ute hydrolysis of aqueous tissue extracts with 10 N HCl. Recovery of added glyceryl- phosphorylcholine was quantitative within limits of error of the method (+ 5%) .
Schmidt, G., B. Ottenstein, W. A. Spencer, C. Hackethal, andS. J. Thannhauser
1957. Quantitative partition of acetal phospholipides and of free lipide alde-
A hydes. Federation Proceedings, 16:
832-835. ~
The lipid aldehydes are converted to Schiff-negative compounds by incubation for 16 hours in an aqueous emulsion at pH 8.3 and room temperature. The acetal phospho- lipids are then determined colorimetrically using Schiff's reagent.
Schmidt, G.
1958. Quantitative estimation of fatty acids on filter paper . Naturwissen-
# schaften, 45: 41. Chemical Abstracts,
52: 885 Id (1958). Mercuric acetate esters of the fatty acids are chromatographed on filter paper and located by conversion of the acetate to sul- fide.
61
Schmidt, L. H.
1935 . The nature of the difference in phospholipid content of oxalated and A heparinized plasma. Journal of Bio-
logical Chemistry, 109: 449-453. The higher phospholipid content of heparinized plasma than of oxalated plasma is due to shrinkage of red blood cells and consequent increase in plasma volume of the oxalated blood.
Schmidt-Neilson, K.
1942. Microtitration of fats in amounts of 10" gram. Compte rendu des _ travaux du laboratoire Carlsberg,
* Serie chimique, 24: 233-246. Chem- ical Abstracts, 38:2225^(1944).
The sample is saponified, and the fatty acids are freed, extracted with toluene, and titrated with tetramethylammonium hydrox- ide.
Schmidt-Neilson, K.
1944. Microdetermination of the iodine number of fat in quantities of 10"^ gram. Compte rendu des travaux du labora- % toire Carlsberg, Serie chimique, 25:
87-96. Chemical Abstracts, 40:20^3 (1946). The I number is determined by saturating the double bonds with Br .and titrating ex- cess Br iodometrically.
Schmidt-Neilson, K.
1944. Extraction and fractionation of
the lipides in one milligram of tissue.
Compte rendu des travaux du labora- ^ toire Carlsberg, Serie chimique, 25:
• 97-105. Chemical Abstracts, 40:21737 (1946).
Frozen tissue is sliced and the tissue is destroyed with KOH. Unsaponifiable lipids are extracted with toluene, the fatty acids are freed from their soaps by adding HCl, and the freed fatty acids are extracted with tolutne .
Schon, H. and F. Gey
1956. Elution chromatographic separa- . tion of free and esterified cholesterols
in organ and serum fats and direct col- orimetric determination. Zeitschrift
flir physiologische Chemie, 303: 81- 90. Chemical Abstracts, 50:"l693 4f (1956). Free and ester cholesterol were separated from fat by elution from an AI2O3 column with petroleum ether-ethanol mixtures. The cholesterol was estimated by the Tschugaeff reaction .
Schoenheimer, R . and W . M . Sperry
1934. A micromethod for the determina- tion of free and combined cholesterol ■ (cholesterol in blood). Journal of Bio-
logical Chemistry, 106: 745-760. Free cholesterol is precipitated as the digitonide, and total cholesterol is precip- itated as the digitonide after hydrolysis of the sample. The color is developed with acetic acid, acetic anhydride, and sulfuric acid, and read at 610-620 mp. . The method requires 0.2 cc. of serum or blood. Stand- ard deviation for free cholesterol is 1.48%; for total cholesterol is 1. 16%.
See Sobel and Meyer (Journal of Biological Chemistry, 157: 255, 1955) for a modifica- tion for use with free cholesterol.
Schuette, H. A. andS. Dal Nogare
1951. An oxidation-adsorption method for analysis of methyl ester fractions . ■^ Journal of the American Oil Chemists
# Society, 28: 229-231. Chemical Ab- stracts. 45:6402g(1951).
A method is described for the separation of saturated from unsaturated methyl esters of the fatty acids. The unsaturated compo- nents are oxidized with permanganate, and the oxidation products are adsorbed on a column of alumina which has been treated with bromothymol blue .
Schwarz, H. P.,, L. Dreisbach, R. Childs, and S. V. Mastrangelo
1957. Infrared studies on tissue lipides. Annals of the New York Academy of
* Sciences. 69: 116-130.
Tissue lipids were chromatographed on silicic acid with MeOH and CHCl3-MeOH as eluting solvents, and the eluted fractions were analyzed by infrared spectrophoto- metry.
62
Seher, A.
1956. Determination of paper-chroma- tographically separated long-chain • carboxylic acids by photometric means .
J Fette, Seifen, Anstrichmittel, 58: 498-
* 504. Chemical Abstracts, 52:4211h
(1958). Fatty acids are separated by paper chro- matography of their copper soaps, and the separated soaps are eluted from the paper and determined by photometry and polar - ography .
Silk, M . H . and H . H . Hahn
1954. The resolution of mixtures of C25-C24 normal -chain fatty acids by ■^ reversed-phase partition chromatog-
0 raphy. Biochemical Journal, 56: 406-
410. ~
An extension of the method of Howard and Martin (Biochemical Journal, 46: 421, 1950). 0^^-024 normal fatty acids are chromato- graphed on a paraffin -coated kieselguhr col- umn with aqueous acetone as developing solvent.
Seki, T.
1958. Chromatographic separation of
. lower fatty acids . Journal of Biochem-
* istry (Tokyo) 45: 855-860. Chemical
• Abstracts, 53:63 26d( 1959).
A method is described for the separation of the lower fatty acids by chromatography on Amberlite IRC-50 resin.
Sheftel, A. G.
1944. Determination of total and free cholesterol. Journal of Laboratory and Clinical Medicine, 29: 875-878.
Glacial acetic acid is used to produce a more stable color in the Liebermann-Bur- chard reaction.
Showell, J. S.
1959. A uniform basis for reporting analytical data on fatty materials. Journal of the American Oil Chemists Society, 36: 343-345. Chemical Ab- stracts, _53:18513b (1959).
A recommendation is presented for re- porting of iodine number, saponification number, acid number, hydroxyl number, acetyl number, peroxide value, carbonyl oxygen, and oxirane oxygen in basic units in order to simplify the correlation of data from different sources. Equations for cal- culation of the numbers are given .
Siegel, L.
1945. The microbiological determination of choline. Science, 101: 674-675.
Constant weight is more easily attained if fritted glass filters are used in place of paper for filtration of the mold growth .
Silk, M. H., H. H. Sephton, and H. H. Hahn 1954. South African pilchard oil . 2. Concentrates of highly unsaturated ^ fatty acids and alcohols derived from
South African pilchard oil. Biochem - ical Journal, 57: 574-577. Urea adduct formation and lithium soap- acetone fractionation are used to separate the highly unsaturated fatty acids from pil- chard oil. A discussion of the merits of each system and comparison of their effec- tiveness is given.
Silk, M . H . and H . H . Hahn
1954. South African pilchard oil . 3. . The fatty acid composition of South
_ African pilchard oil. Biochemical Jour-
• nal, 57: 577-582.
The techniques of lithium soap-acetone separation, distillation, chromatography, and urea adduct formation are used to sub- divide the fatty acid fractions of pilchard oil. The composition of the oil can then be calculated without isolation of the individual acids .
Simmons, R. O. and F. W. Quackenbush
1953. Chromatographic separation of un- saturated fatty acids as their 2,4-dinitro- •^ benzenesulfenyl chloride der'ivatives.
# Journal of the American Oil Chemists Society, 30: 614-616.
The 2,4-dinitrobenzenesulfenyl chloride derivatives of unsaturated fatty acids were separated by chromatography on MgS04 . Saturated acids did not form derivatives.
Sinclair, R. G. andM. Dolan A 1942. The so-called ether -insoluble
63
phospholipids in blood and tissues.
Journal of Biological Chemistry, 142:
659-670. Acetone alone precipitated 40-70% of the phospholipid from plasma and tissues when 0.3 to 2 mg. of phospholipid in 1 cc. of pe- troleum ether and 7 cc . of acetone were used. Complete precipitation was achieved on addition of 1 drop of saturated or 0.1 cc . of 30% MgCl,-6H20 in 95% ethanol. Addi- tion of more MgCl2 caused incomplete pre- cipitation. WhenMgCl2 was not used for precipitation, all of the tissue phospholipid and most of the plasma phospholipid precip- itated were soluble in moist ether. The percentage of ether -insoluble phospholipid precipitate increased in proportion to the amount of MgCl2 used, up to about 20% for the tissue phospholipid, and 90% for the plasma phospholipid. The ether -insoluble portion was found to be a portion of the to- tal phospholipid mixture, and not simply the sphingomyelins.
Sloot, W. J. T. A. K.
1939-40. Determination of total fat con- tent in small amounts of tissue. Acta
^ Neerlandica morphologiae normalis et
pathologicae, 3: 406. Chemical Ab- stracts, 37:40l4 (1943). Lipids are extracted from dried tissue with absolute EtOH and the solvent is evap- orated. The dry lipid is oxidized with K2Cr207 and Ag reagent, KI is added, and excess dichromate is titrated with Na2S203.
Smits, G.
1957. Modification of the periodide meth- od for the determination of choline. Biochimica et Biophysica Acta, 26: 424- 427. ~
The choline periodide precipitate is dis- solved in ethylene dichloride which contains a little iodine, and water is added. The ex- tinction of the ethylene dichloride solution of choline periodide is measured at 365 m u. The interfering I'"' ions remain in the water phase.
Snyder, F . and N . Stephens
1959. Simplified spectrophotometric de- # termination of ester groups in lipids.
Biochimica et Biophysica Acta, 34: 244- 245. A simplification of the hydroxamic acid- ferric perchlorate spectrophotometric meth- od which is adapted for use with multiple samples. The color can be developed in 20 to 30 samples in 15 to 20 minutes. Range to 4.00 micro equivalents of ester.
Sobel, A. E., I. J. Drekter, andS. Natelson 1936. Estimation of small amounts of cholesterol as the pyridine cholesteryl
■ sulfate . Journal of Biological Chemis- try, 115: 381-390.
A method is described for determination of free, esterified, and total cholesterol in the same sample of blood serum . The free cholesterol is isolated as pyridine choles- teryl sulfate, and measured colorimetri- cally by the Liebermann-Burchard reaction. Esterified cholesterol is determined in the same manner after hydrolysis of the cho- lesterol esters. Recovery of 0.025 mg. of added cholesterol was quantitative (+ 4%), with better recovery when large amounts were used.
See also: Drekter, Journal of Biological Chemistry, 115: 391, 1936.
Sobel, A . E . and A.M. Mayer
1945. Improvements in Schoenheimer- Sperry method for determination of
■ free cholesterol. Journal of Biological Chemistry, 157: 255-264.
Extraction of the serum at room temper- ature was found to be as good as the hot ex- traction of S & S . Fifty percent alcoholic digitonin gave a more workable precipitate than the aqueous digitonin of S & S. Precip- itation of cholesterol was found to be com- plete in 3 hours at 37° .
Sobel, A. E., J. Goodman, andM. Blau 1951 . Cholesterol in blood serum . Studies of microestimation as the
■ pyridinium cholesteryl sulfate . Ana- lytical Chemistry, 23: 516-519.
A method for determination of choles- terol as the pyridinium cholesteryl sulfate is described. Cholesterol is dissolved in CCI4, and pyridine and chlorosulfonic acid are added. The resulting precipitate
64
is dissolved in acetic acid and estimated colorimetrically by the Liebermann-Bur- chard reaction. Values by this method are similar to those obtained with digitonin .
Sorrel, M. F. and R. Reiser
1957. Identification of some marine oil constituents by chromatography. Jour- ■^ nal of the American Oil Chemists Soci-
ety, 34: 131-134. Marine oils were separated into fractions on a silicic acid column and the fractions were further separated by chromatography on silicic acid-impregnated paper. Rj values of several components are given.
Soyenkoff, B. G.
1952. An improved micromethod of phos- phate determination. Journal of Biolog- ^ ical Chemistry, 198: 221-227.
A modification of the method of Soyenkoff (Journal of Biological Chemistry, 168: 447, 1947) which eliminates many interferences.
2-p-dimethylaminostyrylquinoline etho- sulfate and ammonium molybdate are added to the digested samples and the resulting color is measured colorimetrically. Sen- sitivity of the method is about 15 times that of the Fiske-Subbarow method. Accuracy with serum filtrates is 2%.
Sperry, W. M. and R. Schoenheimer
1935. A comparison of serum, heparin- ized plasma, and oxalated plasma in ■ regard to cholesterol content. Journal
of Biological Chemistry, 110: 655-658. The content of total and free cholesterol in oxalated blood plasma was found to be lower than in serum or heparinized plasma from the same blood sample. Cholesterol content of serum and heparinized plasma was the same.
Sperry, W. M,
1942. Electrophotometric microdeter- mination of phosphorus in lipide ex- tracts. Industrial and Engineering Chemistry, Analytical Edition, 14: 88- 90. ~
A method is described for the determina- tion of 2 to 25 ug. of lipid phosphorus using reduced concentrations of the Fiske-
Subbarow reagents and spectrophotometric measurement at about 400 m u. Reagent concentrations and temperature are not critical. Recovery of added phosphorus is quantitative.
Sperry, W. M. and F. C. Brand
1943. The colorimetric determination of cholesterol . Journal of Biological Chem-
" istry, 150: 315-324.
A method for the determination of total cholesterol using the Liebermann-Burchard color reaction. Time of development and temperature are critical . Saponification with KOH is necessary, as esterified cho- lesterol develops a stronger color faster than free cholesterol.
Sperry, W . M . and M . Webb
1950. A revision of the Schoenheimer- Sperry method for cholesterol deter - ■ mination . Journal of Biological Chem-
istry, 187: 97-110. Dilute (50%) alcoholic solution of digitonin was found to be preferable to aqueous solu- tions of digitonin, as the aqueous solutions may lose the ability to quantitatively precip- itate cholesterol as they age. Precipitation of the digitonide is net complete in 3 hours at 37° . The precipitation appears to be in- dependent of the amount of cholesterol pres- ent in normal sera. Recovery of 99-101% was obtained.
Sperry, W. M.
1954. _ A method for the determination of total lipids and water in brain tissue. # Journal of Biological Chemistry, 209:
377-386. Tissue is homogenized and an aliquot of the homogenate is weighed. Water is ex- tracted with acetone and evaporated, and the tissue is dried to constant weight in a desic- cator . Difference in tissue weight = water removed. Lipids are extracted and. washed according to Folch, et al (Journal of Biolog- ical Chemistry, 191: 833, 1951) and weighed.
TTiis method for determination of water avoids errors from high temperature dry- ing.
65
Sperry, W . M . and F . C . Brand
1955. The determination of total lipides in blood serum . Journal of Biological
• Chemistry, 213: 69-76.
Lipids are determined gravimetrically after CHCl3-MeOH extraction and purifica- tion. The use of N2 atmosphere helps to overcome partial insolubility of the lipid residue. Sperry' s (Journal of Biological Chemistry, 209: 377, 1954) and Folch's (Federation Proceedings, 13: 209, 1954) purification procedures remove all urea and presumably all other water-soluble contaminants .
Sperry, W. M.
1955. Lipide analysis. In Methods of Biochemical Analysis (D. Click, Ed-
# itor). New York, Interscience Publ. Inc., Vol. U, pp. 83-111.
A description and discussion of methods of lipid analysis suitable for use with blood tissues.
Spiteri, J . and G . Nunez
1952. Partition chromatography of fat- . soluble substances. Compte rendu,
* 234: 2603-2604. Chemical Abstracts,
• 47:941f (1953).
A method is described for the separation of higher fatty acids, alcohols, sterols, vitamins, etc. from a mixture by chroma- tography on triglyceride -impregnated fil- ter paper.
Spiteri, J.
1954. Partition chromatography of fat
. acids. Bulletin de la Societe de chimie
* biologique, 33: 1355-1362. Chemical
• Abstracts, 49: 1325f (1955).
Good separations of higher fatty acids were obtained by chromatography on paraf- fin-impregnated filter paper.
Stahli, H.
1955. Determination of the iodine num- ber. Mitteilungen aus dem Gebeit der Lebensmitteluntersuchung und Hygiene, 46: 121-162. Chemical Abstracts, 49: 14345b (1955).
A comparison of the Hanus, Kaufmann, and Wijs methods. A modification of the
Wijs solution is presented.
Stern, I. andB. Shapiro
1953 . A rapid and simple method for the determination of esterified fatty acids
# and for total fatty acids in blood. Jour- nal of Clinical Pathology, 6: 158-160.
A method is described for determination of fatty acids by hydroxamic acid formation and colorimetric measurement of the color produced with FeCl3 . Standard deviation + 4%.
Stewart, C. P. and E . B. Hendry
1935. The phospholipins of blood. Bio-
A chemical Journal, 29: 1683-1689.
The Fiske-Subbarow method for deter- mination of phosphorus is discussed. Con- ditions for accurate use of the F-S method are described.
Stoffel, W., F. Chu, and E . H. Ahrens, Jr. 1959. Analysis of long-chain fatty acids j^ by gas-liquid chromatography. Micro-
^ method for preparation of methyl esters.
• Analytical Chemistry, 31: 307-308.
A method is described for preparation of methyl esters of long-chain fatty acids ob- tained from biological material. 1 to 10 mg. of the lipid material is dissolved in a meth- anol-5% HCl-benzene mixture and inter- esterified by refluxing at 80-100° for 2 hours. The methyl esters are isolated from the reaction mixture by microsubli- mation and are then ready for separation by gas -liquid chromatography. Recovery of esters is over 95% of theory.
Sturges, S. and A. Knudson
1938. Application of the Schoenheimer- Sperry method to the determination of cholesterol and cholesterol esters in tissues. Journal of Biological Chemis- try, 126: 543-550. A microcolorimetrlc method for deter- mination of tissue cholesterol which is based on the Schoenheimer -Sperry method (Journal of Biological Chemistry, 106: 745, 1934) is described.
Surrey, B. D.
1954. Modified iodometric determination
66
of organic peroxides. Analyst, 79:
86-90. The method is similar to that of Lea (Journal of the Society of Chemical Indus - try, ^: 106, 1945). The reagents are all mixed in a boiling solution of AcOH and CHCI3, which makes deaeration of the re- agents and use of an inert atmosphere un- necessary.
Svennerholm, L .
1954. Partition chromatography of brain , gangliosides on cellulose. Acta chem-
ica Scandinavia, 8: 1108. Gangliosides were separated from the lipid extract of gray matter of human brain by chromatography on cellulose.
Swahn, B.
1952. A method for the localization and determination of serum lipids after
■^ electrophoretic separation on paper.
9 Scandinavian Journal of Clinical and
Laboratory Investigation, 4: 98-103. Lipid components of serum are separated by paper electrophoresis and treated with a 50% alcoholic solution of Sudan Black . The color absorbed by the lipids may be meas- ured by direct colorimetry on the paper, or by elution of the spots and reading in a col- orimeter .
Swahn, B.
1953. Studies on blood lipids: I. A micro- method for determination of total lipids in serum. II. A micromethod for deter- mination of serum lipids after electro -
^ phoretical separation on filter paper .
III. Electrophoretical mobility of "chy- lomicrons" . Scandinavian Journal of Clinical and Laboratory Investigation, 5 (Suppl . 9): 1 14 pp . A method for determination of total lipids in 0.02 ml. of serum is described. The se- rum is placed on a filter paper and dried, and the paper is placed in an ethanolic solu- tion of Sudan Black B. After washing and drying, the dissolved dye is extracted and its concentration is measured colorimetri- cally. Effects of variables are discussed. Error is 1.89%.
See also: Bernes and McDonald (Archives
of Biochemistry and Biophysics, 70: 49, 1957), who separated Sudan Black into 10 components by chromatography. All frac- tions were found to stain lipids, but to vary- ing degrees .
Swem, D., H. B. Knight, O. D. Shreve, and M. R. Heether
1950. Comparison of infrared spectro- photometric and lead salt alcohol meth- ods for determination of trans -octa- _ decenoic acids and esters. Journal of
the American Oil Chemists Society, 27: 17-21. Chemical Abstracts, 44:2260f~ (1950). The infrared method was found to be more accurate, specific, and rapid than the lead salt method.
Szent-Gyorgi, A.
1957. Detection of chromatographic spots on paper . Science, 126: 75 1 . The developed chromatogram is cooled in liquid nitrogen and viewed under ultra violet light. Spots may be detected by their phos- phorescence.
Taurog, A., C. Enteiunan, B. A. Fries, and I. L. Chaikoff
1944. An adsorption procedure for the separation of choline -containing from "^ non -choline -containing phospholipids
A of liver. Journal of Biological Chemis-
try, 155: 19-25. Total phospholipids are adsorbed on MgO and the choline -containing phospholipids are eluted with MeOH.
Taylor, W . E . and J . M . McKibbin
1953. The determination of lipide inosi- tol in animal tissues. Journal of Bio- logical Chemistry, 201: 609-613. A method is described for determination of inositol in tissues by microbiological assay with Saccharomyces carlsbergensis on the acid hydrolysates of purified lipid extracts and turbidimetric measurement of the yeast growth.
It was inconvenient to use Saccharomyces cerviseae as the test organism as its me- dium turns very dark after autoclaving, mak- ing direct turbidimetric readings unsuitable .
67
Teeri, A. E.
1944. On the determination of esterifled cholesterol. Journal of Biological Chem- " istry, 156: 279-281.
Esterified cholesterol was found to pro- duce approximately 25% more colot with Liebermann-Burchard reagents than free cholesterol .
Teorell, T.
1931. Spectrophotometric determination of phosphorus . Biochemische Zeit- A schrift, 230: 1-9. Chemical Abstracts,
25: 1756 (1931). A modification of the Fiske-Subbarow method for use in the determination of 0.01 to 0.05 mg. P by spectrophotometry. Accu- racy of the method is +2%.
Thaler, H. and E. Just
1944. Determination of the phosphatide content of fats . Fette und Seifen, 51: A 55-59. Chemical Abstracts, 42:1069d
(1948). A method for determination of phospha- tides by burning off the organic matter in the presence of MgO and precipitation of P as ammonium phosphomolybdate is described.
Thaler. H.
1952. Determination of phosphorus in fats of low phosphatide content. Fette und A Seifen, 54; 763-765. Chemical Ab-
stracts, _47: 6675b (1953). Details are given of a method for deter- mination of phosphorus in fats containing little phosphatide by an adaptation of the method of Beveridge and Johnson (Canadian Journal of Research, 27E: 159, 1949).
Thannhauser, S. J., J. Benotti, andH. Rein- stein
1939. Studies on animal lipids. XIV. The determination of lecithin, cephaUn, and sphingomyelin in body fluids and A tissues; with analyses of normal human
sera . Journal of Biological Chemistry, 129: 709-716. Sphingomyelin is determined as the reineckate according to Thannhauser and Setz (Journal of Biological Chemistry, 116: 533, 1936) except that the precipitate is washed with acetone to remove reineckate other than sphingomyelin, and the sphingo- myelin calculation is based on phosphorus content of the reineckate rather than total weight of the precipitate.
Choline is liberated by hydrolysis with gaseous HCl in methanol and determined as the reineckate.
The value of lecithin is calculated as the difference in sphingomyelin and choline values, and cephalin is calculated as the difference in total and choline -containing phospholipids .
Thannhauser, S. J., J. Benotti, and N. F. Boncoddo 1946. The preparation of pure sphingo- ■^ myelin from beef lung and the identifica-
0 tion of its component fatty acids . Journal of
A Biological Chemistry, 166: 677-681.
Pure sphingomyelin was prepared by alka- line saponification or by exhaustive extrac- tion with 97% acetone in water of crude sphingomyelin extracted from lung. The fatty acids were identified by vacuum distil- lation and recrystallization, followed by direct titration of the free acids .
Thannhauser, S.J. and P. Setz
1936. Studies on animal Upids . XI. The reineckate of the polydiamino phospha- A tide from spleen. Journal of Biological
Chemistry, 116: 527-531. Diaminophosphatide is prepared by con- tinuous extraction with MeOH-CHCl3 (1:1) from freeze-dried tissue. Monoaminophos- phatide was separated from diaminophos- phatide by precipitation of the diamino as the reineckate.
Thannhauser, S. J., N. F. Boncoddo, and G. Schmidt
1951 . Studies of acetal phospholipides of brain. I. Procedure of isolation of crys- ■^ tallized acetal phospholipide from brain.
A Journal of Biological Chemistry, 188:
417-421. A method is described for the isolation and purification of acetal phospholipid from beef brain by a series of solvent extractions and saponification.
68
Theile, O. W.
1958. A method for the determination of total Upides in organs . Zeitschrift
fiir physiologische Chemie, 311: 136- • 139. Chemical Abstracts, 52:156331
(1958) The tissue is lypholized, and the lipid is extracted with CHCl3-MeOH (1:3) under re- flux. The extract is evaporated, the resi- due is dissolved in CHCl3-MeOH (2:1), over- laid with H2O, and left standing overnight . The water is removed, and the lipid mate- rial is dried and weighed.
Thompson, A. R.
1950. A colorimetric method for the determination of esters . Australian
Journal of Scientific Research, (A) 3: * 128-135. Chemical Abstracts, 45:499f
(1951). An extension of the colorimetric method of Hill (Industrial and Engineering Chemis- try, Analytical Edition, 18: 317, 1946; Ana- lytical Chemistry, 19: 932, 1947) for deter- mination of esters as their hydroxamic acid derivatives. The method is for use in de- termination of volatile esters and includes fixed reaction times and lower reaction temperature .
Thompson, A. R.
1951. Separation of saturated monohy- droxamic acids by partition chroma- •^ tography on paper . Australian Journal
% of Scientific Research, (B) 4: 180-186.
Chemical Abstracts, 46:427f'(1952). The lower hydroxamic acids were sep- arated by paper chromatography using var- ious solvent systems, and located on the chromatograms by spraying with FeCl3 solution.
Thornton, M . H . and F . K . Broome
1942. Determination of choline . A photo- metric modification of Seattle's meth- od. Analytical Chemistry, 14: 39-41. Choline reineckate in acetone solution is nieasured colorimetrically. For use with 0.6 to 16.0 mg. of choline. Maximum error is 2%.
Toms, H.
1928. Oil bromide films and their use in
determining the halogen absorption
of oils. Analyst, 53: 69-97. The unsaturation of an oil is determined by absorption of bromine vapor and gravi- metric determination of the change in wei^t of the sample caused by the bromine ab- sorbed. Results by this method are in ac- cord with Wijs determination.
Tom sett, S. L. andW. S. Tennant
1956. A method for determining esteri- fied fatty acid with zone electrophoresis 9 of serum proteins . American Journal
of CUnical Pathology, 26: 1226-1230. After electrophoresis of serum, the fatty acids are extracted from the paper and de- termined spectrophotometrically as their hydroxamic acid derivatives.
Tomsett, S. L.
1958. The determination of formaldehyde and acetaldehyde liberated in the per- iodate and ninhydrin reactions . Ana- lytica Chimica Acta, ^: 360-363. (In English). Chemical Abstracts, ^: 20921 (1960). Formaldehyde and acetaldehyde are sep- arated by aeration and are determined col- orimetrically by means of chromotropic acid atid p-hydroxybiphenyl, respectively. The method is suitable for determination of acetaldehyde and formaldehyde liberated by reaction of sugars, serine and threonine with periodate, and glycine and alanine with ninhydrin.
Tourtellotte, W. W., A.J. Vander, B. A. Skrentny, and R.N. Dejong
1958. A study of lipids in the cerebro- spinal fluid. II. The determination of 0 total lipids. Journal of Laboratory and
Clinical Medicine, 52: 481-490. A method is described for the determina- tion of 2 jxg. of total lipids by oxidation with dichromate-sulfuric acid reagent and color- imetric measurement of the reduced chro- mium ion.
69
Tourtellotte, W. W., F. M. Parker, and R. N. Dejong
1958. A study of lipids in the cerebro- spinal fluid, ni. The determination of total phospholipids. Journal of Labora- tory and Clinical Medicine, 52: 491- 495.
The method is based on co -precipitation of proteins and lipids, determination of phosphorus on an aliquot using HCIO4- H2SO4 for ashing, and colorimetric meas- urement of molybdate color developed with ascorbic acid as reducing agent. The meth- od is capable of determining 0.7 m^moles (0.02^g.) of phospholipid with coefficient of variation of about 5%.
Tourtellotte, W. W., B. A. Skrentny, and R, N. Dejong
1959. Lipides in the cerebrospinal fluid. IV . The determination of free and total
■ cholesterol. Journal of Laboratory and
Clinical Meditine, 54: 197-206. A method is described for determination of cholesterol in 0.25 ml. of cerebrospinal fluid. The proteins and lipids are co -pre- cipitated with trichloracetic acid and the lipids are extracted from the precipitate. Total cholesterol is determined fluoromet- rically by the procedure of Albers and Lowry (Analytical Chemistry, 27: 1829, 1955) and free cholesterol by a modifica- tion of the Sperry and Webb method (Jour- nal of Biological Chemistry, 187: 97, 1950). The method is capable of determining 1 ug. of free cholesterol and 0.5^ g. of total cholesterol with variations of 3 and 7%, re- spectively.
Trappe, W.
1938. Modification of the Kaufmann meth- od for determining the iodine number for very small amounts of fat. Bio- chemische Zeitschrift, 296: 180-185. Chemical Abstracts, 33: 420^(1939). The fat (0.2 to 2.0 mg.) is dissolved in CHCI3, brominated with Br2 in MeOH, and titrated iodometrically.
Trappe, W.
1940. Separation of biological fats from "At natural mixtures by means of adsorp-
tion columns. I. The eluotropic series of solvents. Biochemische Zeitschrift, 305:^ 150-161. ~ (1941).
Chemical Abstracts, 35:
477*^
The "eluotropic series" (solvents arranged according to their eluting power) is given.
Trappe, W.
1940. Separation of biological lipides from their natural mixtures by adsorp- tion columns. II. Isolation of phospho-
. rus- and nitrogen-free lipide fractions.
Biochemische Zeitschrift, 306: 316- 336. Chemical Abstracts, "35:2169^ (1941). The relative adsorbabilities of lipid frac- tions from biological materials are listed.
Trappe, W.
1941 . Separation of biological lipides from their natural mixtures by means of adsorption columns . III. Separation of phosphorus- and nitrogen-free lipide fractions . Biochemische Zeitschrift, 307: 97-106. Chemical Abstracts, 35: 40533(1941).
Free fatty acids with phosphatides were separated from total lipid extract on an Al20q column . An activated Frankonite KL column was used to separate hydrocarbons and cholesterol esters.
Trappe, W.
1942. Determination of free and ester- ified cholesterol in 0 . 1 cc . blood from the finger tip. Klinische Wochenschrift,
" 2j.: 651-652. Chemical Abstracts, 38:
2058^(1944). Blood lipids are adsorbed on 5102- Ester- ified cholesterol is eluted with benzene, free cholesterol is eluted with Et20-CHCl3, the solvents are evaporated, and cholesterol is estimated in each fraction with AcOH-ZnClo and AcCl.
Trappe, W.
1943. Simple method for the separate quantitative estimation of free and esterified cholesterol in blood serum
■ without digitonin precipitation and sapon-
ification . Zeitschrift fiir physiologische Chemie, 273:177-190. Chemical Ab-
70
stracts, 37: 3119^(1943). The cholesterol is extracted from plasma with EtOH -petroleum ether (2:3), and the extract is dried and evaporated. The resi- due is dissolved in CCI4 and chromato- graphed on an AI2O2 column. Esterified cholesterol is eluted with CCl^ and free cholesterol with CHCI3, and cholesterol content of each fraction is estimated color- imetrically using ZnCl2-AcOH and AcCl.
Trinder, P.
1952. Determination of cholesterol in
■ serum. Analyst, 77: 321-325. Cholesterol esters are hydrolyzed by
heating the serum with alcoholic KOH, and the cholesterol is extracted with petroleum ether. Color is developed with acetyl chloride -sulfuric acid.
Trusov, V. I.
1950. Determination of choline in biolog- ical materials. Biokhimiya, 15: 495- 498. Chemical Abstracts, 45:3448f (1951). Choline is precipitated as the reineckate, the Cr is oxidized by KBrOg or H2O2, and the resulting chromate is titrated with Na2S203 .
Turner, M. E.
1931 . A simplification of the Okey meth- od for the determination of cholesterol
■ by the oxidation of the digitonide . Jour nal of Biological Chemistry, 92: 495-498.
A modification of the Okey method (Journal of Biological Chemistry, 88: 367, 1930) for oxidation of cholesterol digitonide.
Twltchell, E.
1921. The precipitation of solid fatty , acids with lead acetate in alcoholic so-
^ lution. Journal of Industrial and Engi-
* neering Chemistry, 13: 806-807.
A method is described for separation of the liquid and solid fatty acids in which the solid acids are precipitated from a hot al- coholic solution by addition of lead acetate and cooling. The liquid acids remain in solution and are filtered off.
Uzman, L. L.
1953 . A general method for the prepara- tion of cerebrosides. Archives of Bio- chemistry and Biophysics, 45: 149-155. Tissue is homogenized and extracted with CHCl3-MeOH (2:1) and trichloracetic acid is added. The mixture is centrifuged, the upper and lower layers of the three-phase system are drawn off, and the interphase layer is dialyzed against distilled water. The resulting material is recrystallized from alcohol-chloroform (1:1). 65-75% of the total tissue cerebrosides are obtained from spleen and brain .
Van Beers, G. J., H. De longh, and J. Boldingh 1957. Isolation of phospholipides by dialysis through a rubber membrane. Essential Fatty Acids. Proceedings of '^ the International Conference on Biochem-
A ical Problems of Lipids, 4th Oxford,
(Pub. 1958) pp. 43-47. Chemical Ab- stracts, 53:17278a (1959). A method is described for separation of phospholipids from lipid mixtures by dialy- sis through a rubber membrane. The phos- pholipids do not pass through when a non- polar solvent is used.
Van de Kamer, J. H., N. A. Pikaar,
A. Bolsaens-Frankena, C. Couvee-Pioeg, and L. van Ginkel
1955. Quantitative determination of the different higher saturated fatty acids
. in fat from blood, chyle, and faeces,
by means of partition chromatography
* on rubber. Biochemical Journal, 61: 180-186. ~
The fats are extracted and saponified, and the fatty acids are extracted from the hydrol- ysate. The unsaturated fatty acids are oxi- dized with KMn04, and the saturated fatty acids are separated on a rubber chromato- graphic column with acetone -water solvent mixtures .
Vandenheuvel, F. A. and D. R. Vatcher
1956. Partition chromatography of ali- phatic acids. Quantitative resolution
^ on normal chain even acids from Cj^2
# to C24. Analytical Chemistry, 28: 838- 845.
71
C.2-C24 ^^^^y acids were chromatograph- ed on a dichlorodimethylsilane-treated col- umn of silicic acid by using 2,2,4-trimethyl- pentane as stationary phase and eluting with aqueous methanol . The eluted acids are measured by titration. Error is less than
2.5%-
An apparatus for automatically and con- tinuously changing the composition of the eluting solvent and a semiautomatic, motor driven microburette are described.
Van Handel, E .
1959. Separation and chemical assay of
# lipide classes . Journal of the Ameri- A can Oil Chemists Society, 36: 294-297. ■ Chemical Abstracts, 53:17226h (1959).
A review and discussion of methods for microdetermination of cholesterol, triglyc- erides, and phospholipids .
Van Handel, E. and D. B. Zilversmit
1953. Micromethod for the direct deter- mination of serum triglycerides . Jour-
# nal of Laboratory and Clinical Medicine, 50: 152-157.
Triglycerides are determined as glycerol by the chromotropic acid method of Lambert and Neish (Canadian Journal of Research, 28: 83, 1950) after quantitative removal of phosphatides and saponification.
Wachsmuth, H. and L. van Koeckhoven
1959. The determination of choline in blood serum . Clinica Chimica Acta, 4: 206-212 (In French). Chemical Ab- stracts, 53:12381g(1959). Precipitation of choUne by silico-tungstic acid and reduction of the silico-tungstate with HSO3" gives a color reaction which is 600 times more intense than the choline reineckat^ reaction.
Weigensberg, B. I. andG. McMillan
1959. Ultraviolet spectrophotometric
method for the determination of choles- ■ terol . American Journal of Clinical
Pathology, 31: 16-25.
Serum or tissue cholesterol or the cho- lesterol digitonide is determined by spectro- photometric measurement of the absorption of UV lig^t at 204-206 mjx . The method is simple and reproducible, and is 3 to 4 times more sensitive than the Schoenheimer- Sperry method.
Weil, L. andM. A. Russell
1942. Studies on plasma phosphatase activity and on blood phospholipids in ▲ rats with obstructive jaundice . Journal
of Biological Chemistry, 114: 307-314. A method is described for the determina- tion of the phospholipids in an alcohol -ether extract of 8 mm? of plasma or 4 mm? of blood by a micro modification of the method of Boyd (Journal of Biological Chemistry, 144: 223, 1936). The phospholipids are digested with HCIO4 and color is developed with am- monium molybdate, using aminonaphtholsul- fonic acid as reducing agent.
Weiss, B 1957
•
▲
The separation of sphingolipides by adsorption chromatography. Jour- nal of Biological Chemistry, 223: 523- 534. A method is described for chromatograph- ic separation of sphingolipides of the central nervous system by gradient elution with chlo- roform and methanol from a silicic acid col- umn.
Attempts to use the method of Taurog, et al, (Journal of Biological Chemistry, 155: 19, 1944) for separation of choline -contain- ing from non-choline-containing phospho- lipids on magnesium oxide were unsuccess- ful.
Diminished resolving power was observed when Hyflo Super -Cel was added to the ad- sorbent, or when the silicic acid was added to the column as a chloroform suspension rather than a chloroform -methanol suspen- sion.
72
Wheeldon, L. W. and F. D. Collins
1957. Studies on phospholipids. I. The determination of amino nitrogen in un-
A hydrolyzed phospholipids . Bipchem-
ical Journal, 66: 435-441. I-flouro-2:4-dinitrobenzene is reacted directly with the NH2 groups of the unhy- drolyzed phospholipid in the presence of triethylamine, and the colored compounds formed are estimated colorimetrically.
Wheeldon, L. W. and F. D. Collins
1958. Studies on phospholipids. 3. De- termination of choline . Biochemical
^ Journal, 70: 43-45.
The lipid sample is hydrolyzed at 100° in ethanol-HCl. Choline is precipitated as choline phosphomolybdate, washed with iso- butanol, and dissolved in acetone. H2SO4 and SnCl2 are added and the optical density of the blue solution is measured at 630 m;,;. The method agrees closely with the reineck- ate method of Click . Added choline was quantitatively recovered.
White, L. K.
1946. Spectrophotometric determination of glycerol. Oil and Soap, 23: 323- 326. Chemical Abstracts, 41:56d(1947). A procedure for determination of glycerol by spectrophotometric measurement of the blue color of the copper -glycerol complex is described.
White, M . F . and J . B . Brown
1949. A study of the tetrabromide meth- od of estimating linoleic acid in fatty # acid mixtures. Journal of the American
Oil Chemists Society, 26: 385-388. The yield of insoluble tetrabromides from bromination of linoleic acid is affected by the composition of the petroleum ether used as solvent, and by the amounts of linoleic acid and other fatty acids in thg sample used.
Whitehorn, J. C.
1924-1925. A method for the determina- tion of lipoid phosphorus in blood and ▲ plasma . Journal of Biological Chemis-
try, 62: 133-138. The extracted lipids are digested with
H2SO4-HNO3. Molybdate color is developed with sodium sulfite and hydroquinone .
Whittaker, V. P. andS. Wijesundera
1952. The separation of esters of cho- _. line by filter -paper chromatography. ^ Biochemical Journal, 51: 348-351.
Choline esters were separated by paper chromatography using n-propanol- or n-butanol -water as solvents. The esters were detected on the chromatogram by us- ing hydroxylamine- ferric chloride, iodine, or phosphotungstic acid-stannous chloride.
Wiese, H. F. and A. E. Hansen
1953. Semimicromethod for unsaturated _ fatty acids of blood serum . Journal of * Biological Chemistry, 202: 417-423.
The unsaturated fatty acids from 3 ml . of blood serum are isomerized by treatment with 11% KOH in ethylene glycol at 180° for 25 minutes, and read spectrophotometri- cally .
Williams, H. H., B. N. Erickson, I. Avrin, S. S. Bernstein, and I. G. Macy
1938. Determination of cephalin in phos- pholipids by the estimation of choline. ▲ Journal of Biological Chemistry, 123:
111-118. The total phospholipid is determined on an aliquot of tissue extract by Bloor's oxidative titrimetric method (Journal of Biological Chemistry, 82: 273, 1929). Choline is de- termined as the reineckate on a second ali- quot after Ba(0H)2 hydrolysis, and cephalin is calculated as the difference in total and choline -containing phospholipid.
Willis, G. C, Jr.
1950. Preparation of fatty acid methyl _ esters. Chemi st - Analyst, 39: 62.
Methyl esters of the fatty acids may be prepared by treating a methanolic solution of the acid with concentrated H2SO4 and heating to remove excess MeOH. The re- action is essentially complete.
Winzler, R. J. and E. R. Meserve
1945. Spectrometric determination of small amounts of choline . Journal of Biological Chemistry, 159: 395-397, Choline reineckate in acetone is
73
determined spectrophotometrically at 327 m/i. Accuracy is + 5% with 50-400 /i-g. of choline hydrochloride.
Wittenberg, J, B.
1955. The separation of sphingosine and related compounds by reversed phase
-^ partition chromatography. Journal of
Biological Chemistry, 216: 379-390.
After conversion to their N-succinyl de- rivatives with succinic anhydride, sphingo- sine and related compounds are separated on a dichlorodimethylsilane -treated column of diatomaceous earth.
A method for assay of sphingosine com- pounds is proposed which entails conversion of sphingosine and related compounds to their N-succinyl derivatives and titration with alkali of the carboxylic acid group which has been introduced. Three to 100 /imoles were determined with an accuracy of +5%.
Wittenberg, J. B., S. R. Korey, and F. H. Svenson
1956. The determination of higher fatty aldehydes in tissues. Journal of Bio- logical Chemistry, 219: 39-47.
A method is described for the estimation of higher fatty aldehydes in tissue lipids by colorimetric measurement of their p-nitro- phenylhydrazone derivatives. The method is specific for higher aldehydes, and lower aldehydes and keto acids do not interfere. Determines 0. 1 to 7 umoles within 5%.
Wittenberg, J. B.
1957. The separation of the C5-C,2 fatty acids by reversed-phase partition
^ chromatography . Biochemical Journal,
• 65: 42-45.
Chloroform -Skellysolve S-water-methanol solvent systems were used to separate the C^-C j2 fatty acids on a dichlorodimethyl- silane-treated column of Hyflo Super -Cel.
Witter, R. F., G. V. Marinetti, A. Morrison, and L. Heicklin
1957. Paper chromatography of phospho- lipides with solvent mixtures of ketones and acetic acid. Archives of Biochem-
•
istry and Biophysics, 68: 15-20.
Lysolecithin, sphingomyelin, phospha- tidyl ethanolamine, lecithin, andphospha- tidic acid in quantities of 10 to 25 jxg. in 20/^1. were separated by paper chromatog- raphy using mixtures of various ketones and acetic acid as solvent systems.
Wolman, M.
1950. Staining of lipids by the periodic- acid-Schiff reaction. Proceedings of the Society for Experimental Biology and Medicine, 75: 583-585. Schiff's reagent will stain unsaturated lipids after they have been oxidized with per- iodate. Sphingolipids will stain even if they do not contain a carbohydrate.
Woolley, D. W.
1941 . A method for the estimation of ino- sitol . Journal of Biological Chemistry, 140: 453-459.
A basal medium was developed which sup- ported practically no growth under the ex- perimental conditions. Inositol content of the sample material added to the basal me- dium was determined by colorimetric meas- urement of the turbidity produced by the yeast Saccaromyces cereviseae.
It was noted that inositol does not produce marked stimulation unless the basal medium was otherwise complete for optimal growth.
Attempts to use Eastcott's basal medium (Journal of Physical Chemistry, 32: 1096, 1928) were not entirely successful.
WooUey, D. W.
1943 . Isolation and partial determination of structure of soy bean lipositol, a new ■^ inositol -containing phospholipid. Jour-
▲ nal of Biological Chemistry, 147: 581-
591. Lipositol was prepared by extraction with CHCI3 and recrystallization from CHCI3 with methanol and ethanol .
Wren, J. J. and H. K. Mitchell
1958. Silicic acid chromatography of j^ lipids of whole human blood. Proceed-
^ ings of the Society for Experimental
* Biology and Medicine, 99: 431-435.
Blood lipids were separated into 20 com- ponents by chromatography on silicic acid.
74
Wycoff, H. D. and J. Parsons
1957. Chromatographic microassay of
"A" cholesterol and cholesterol esters.
■ Science, 125: 347-348.
Free and esterified cholesterol are sep- arated from about 0.02 ml. of plasma by chromatography on SiOo, and estimated by measurement of the color produced with FeCl3 reagent.
Yasuda, M.
1931. Contributions to the micro deter- mination of cholesterol. Journal of Bio- logical Chemistry, 92: 303-312. Modifications of Okey's procedure (Jour- nal of Biological Chemistry, 88: 367, 1930). Acetone is used to separate the digitonide from excess digitonin and lipid material. The digitonide is freed of impurities by so- lution in hot absolute alcohol and filtration.
Yasuda, M.
1931-2. The determination of the iodine _ number of lipids . Journal of Biological
* Chemistry, 94: 401-409.
The lipids are halogenated with pyridine sulfate dibromide, and the excess halogen is titrated with thiosulfate. The method is combined with determination of total lipid by Bloor's oxidative procedure. Chloroform dissolves the phospholipid precipitated from acetone-MgCl2 as well as moist ether, and dissolves a smaller amount of the MgCl2.
Young, L .
1934. The determination of inositol in animal tissues. Biochemical Journal, 28: 1435-1443. Inositol is extracted from tissue with aqueous acetone, purified by precipitation, and estimated by oxidation with potassium iodomercurate.
Youngs, C. G. andB. M. Craig
1951. A note on the preparation of methyl esters of fatty acids . Journal of the _ American Oil Chemists Society^ 28:
• 521-522. Chemical Abstracts, 46: 1271f (1952).
A method is described for direct conver- sion of saponified fatty acids to their methyl esters with dimethyl sulfate. Yield is over 99%.
Youngs, C. G., A. Epp, B. M. Craig, and H. R. Sallans
1957. Preparation of long-chain fatty
acid chlorides. Journal of the American • Oil Chemists Society, 34: 107-108.
Chemical Abstracts, 51^:7039d (1957). A method is described for preparation of fatty acid chlorides by treating the free acid with PCI5 or PCI3 in an inert organic solvent. Excess chlorinating agent is removed by washing the solvent phase with water. Yield is quantitative, with less than 1 .5% of free acid unreacted.
Zak, B., R. C. Dickenham, E.G. White, H. Burnett, and P. J. Chemey
1954. Rapid estimation of free and total cholesterol. American Journal of Clin- ical Pathology, 24: 1307-1315. Cholesterol is extracted from serum with 50:50 alcohol -acetone. Total cholesterol is determined directly on the dried residue of an aliquot of the extract, and free choles- terol is precipitated with digitonin in another aliquot. Color is developed in both portions with the FeCl3 -acetic acid reagent of Zlatkis, et al (Journal of Laboratory and Clinical Medicine, 41: 486, 1953).
Zak, B., N. Moss, A. J. Boyle, and A. Zlatkis 1954. Reactions of certain unsaturated sterols with acid iron reagent. Ana- lytical Chemistry, 26: 776-777. Colors produced by reaction of various sterols with ferric chloride -acetic acid- sulfuric acid reagent are given.
Zak, B.
1957. Simple rapid microtechnic for serum total cholesterol. American
■ Journal of Clinical Pathology, 27: 583-
588. Serum proteins are precipitated with a ferric chloride -acetic acid solution. A por- tion of the supernatant is diluted with H2SO4 and the resulting color is measured in a spectrophotometer at 560 mu.
Zbinovsky, V.
1955. New solvent for separating mono - ir carboxylic acids (C2 to C^^) and dicar-
# boxylic acids (C2 to 022)- Analytical
75
Chemistry, 27: 764-768. All of the individual saturated fatty acids C2-C14, the C|3-Ci5 fatty acids differing by two C in chain length, and the dicarbox- ylic acids C2 to C22 were separated on a silicic acid column. Methyl cellosolve- water was used as a stationary phase, and Skellysolve B, n-butyl ether, or their mix- tures were used as eluting solvents.
Zilch, K . T . and H.J. Dutton
1951. Analysis of fat oxidation product ■^ by countercurrent distribution methods.
Analytical Chemistry, 23: 775-778. Effects of various functional groups on the distribution of compounds were studied. Partition coefficients are given for a num- ber of model compounds .
Zilversmit, D. B. and A. K. Davis
1950. Micro -determination of plasma phospholipids by trichloracetic acid A precipitation. Journal of Laboratory
and Clinical Medicine, 35: 155-160. A method is described for determination of phospholipids in 0.2 ml. of plasma. The phospholipids are precipitated with trichlo- racetic acid and phosphorus is determined colorimetrically after perchloric acid di- gestion of the precipitate.
Zlatkis, A., B. Zak, and J. Boyle
1953. A new method for the direct deter- mination of serum cholesterol. Jour- ■ nal of Laboratory and Clinical Medicine,
41: 486-492. A sulfuric acid, acetic acid, and ferric chloride reagent is added directly to a 0. 1 ml. sample of serum and the color is read spectrophotometrically at 400-700 m/.i. Cholesterol and cholesterol esters yield the same molar color, thus eliminating the need for saponification . The method compares well with other methods, and is rapid and reproducible.
Zuckerman, J. L. andS. Natelson
1948. A convenient and rapid procedure for total cholesterol estimation using an acid chloroform extraction. Journal of Laboratory and Clinical Medicine, 33: 1322-1325. Sulfuric acid and chloroform are added to the serum sample and mixed. The sample is centrifuged and the acid and precipitated protein are removed. Acetic anhydride and sulfuric acid are added to an aliquot of the chloroform solution and the color is read at 625 m^^. The method requires about 45 min- utes . Results are comparable to those ob- tained by Bloor's extraction method.
76
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