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 . 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 



