Rearrangement of Glyceride Fatty Acids During Digestion and Absorption

Abstract

A number of studies (l-8) have attempted to identify the digestion products of glycerides that are absorbed from the lumen of the intestine. Unfortunately none of these unequivocally established the nature of the absorbed materials. I f they had, they would have revealed also the extent of rearrangement of the fatty acids of the dietary triglycerides. Moreover, because of the type of materials fed or the analytical methods employed, information about the reactions involving a particular fatty acid that occupied a specific position in a triglyceride molecule could not be obtained. There are two reports in the literature of experiments dealing directly with the problem of triglyceride rearrangement during digestion and absorption. Borgstrom (9) concluded from his studies that randomization takes place. A recent paper of Savary, Constantin, and Desnuelle (10) claims that, if randomization takes place, it is limited to certain fatty acids. In the studies reported here, triglycerides of known structure were fed to rats, and the distribution of the fatty acids in the triglycerides of the lymph was determined. The results obtained show that 85 to 90% of the fatty acids occupy the same position on the lymph triglyceride molecule as they did on the dietary triglyceride molecule before the processes of digestion and absorption.