Molecular structure of glycerolipids in rats fed partially hydrogenated triacylglycerols
Reichwald-Hacker, I.; Grosse-Oetringhaus, S.; Kiewitt, I.; Mukherjee, K.D.
Journal of Nutrition 110(6): 1122-1129
1980
ISSN/ISBN: 0022-3166 PMID: 7381584 Document Number: 156744
The positional distribution of acyl moieties was studied in two major classes of glycerolipids, triacylglycerols and diacylglycerophosphocholines, of liver, heart and serum of rats fed on an unhydrogenated soya bean oil (control group) or a partly hydrogenated soya bean oil (experimental group) containing 12.3% trans-octadecenoic acids. In both groups, most of the fatty acids from dietary triacylglycerols were utilized for the synthesis of tissue triacylglycerols according to their dietary availability. Irrespective of the dietary fat, the saturated fatty acids were preferentially esterified at positions 1 and 3 and the unsaturated fatty acids at position 2 of tissue triacylglycerols. In the experimental group very little of the dietary trans-octadecenoic acids was incorporated into positions 1 or 3 or position 2 of tissue triacylglycerols. In diacylglycerophosphocholines of both groups, the dietary and endogenous palmitic and stearic acids were esterified predominantly at position 1, whereas dietary linoleic acid and polyunsaturated fatty acids derived therefrom were esterified almost exclusively at position 2. Relatively large proportions of trans-octadecenoic acids were selectively esterified at position 1 of diacylglycerophosphocholines of the experimental group. Reported specificities of enzymes involved in the biosynthesis of glycerolipids from sn-glycero-3-phosphate satisfactorily account for the positional distribution of acyl moieties.