Absorption of Monoglycerides

¹ From the Department of Biochemistry, The University of Texas, Southwestern Medical School, Dallas, Texas

The rate of absorption of glyceryl monooleate, when fed alone, appeared to be much slower than that of other glycerides. However, the monooleate was found to be relatively unavailable for absorption because a large part of it was retained for a time in the stomach as a thick gel. In contrast, the chylomicronemia was markedly greater after feeding olive oil, Tween 80, or 1:1 mixtures of the glyceryl monooleate and olive oil or the fatty acids prepared from it. The slower absorption of the monoglyceride was not associated with a decreased lipid retention over a longer period, because eventually all of the lipid became available for absorption. In an unsuccessful attempt to prevent excessive gastric retention of this lipid, several 10% emulsions of the monooleate were employed. Observation showed that the retention in these attempts could not be attributed solely to gel formation, but more likely to a decreased gastric motility. Nevertheless, a similar rate of absorption of the monooleate and olive oil was obtained if only that part of the lipid were considered which had passed from the stomach and was therefore readily available for absorption. Insufficient evidence is at hand to determine whether the major hydrolysis of the monoglycerides, which is necessary for formation of the triglycerides of the chyle, occurs in the lumen or the mucosal cell.