In vitro esterification of cholesterol by pancreatic juice and by acetone powder extracts of small intestine: the effect of unsaturated fatty acids upon esterification with saturated fatty acids

Abstract

The esterification of cholesterol by rat pancreatic juice and by extracts of acetone powders of rat small intestine was studied with palmitic, stearic, oleic, linoleic, and linolenic acids. When each fatty acid was tested individually, the extent of esterification was highest with oleic acid and lowest with the two saturated fatty acids. The esterification of cholesterol with palmitic and stearic acids by the intestinal extracts and with palmitic acid by pancreatic juice was greatly increased by the addition of either oleic or linoleic acid to the incubation mixture. It is suggested that the difference between esterification of cholesterol with saturated fatty acids and esterification with unsaturated fatty acids, as well as the enhancement of the esterification with saturated fatty acids by the addition of an unsaturated fatty acid, is accounted for by micellar solubilization of cholesterol and of saturated fatty acid in the presence of an unsaturated fatty acid and bile salts.

Keywords

• cholesterol esters
• biosynthesis
• specificity
• saturated
• unsaturated
• pancreatic juice