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 



