Diacylglycerols digestion

T. Yanagita, Digestion and Absorption of Diacylglycerol, 5th International Congress on Essential Fatty Acids and Eicosanoids, Diacylglycerol and Human Health Session, Taipei, Taiwan, 2002. 

Diacylglycerols arise from action of triacylglycerol lipase on a fat (triacylglycerol), which hydrolyzes one of the three fatty acids from it (at position one or three). Further digestion of the monoacylglycerol requires the action of monoacylglycerol lipase. 

Pancreatic lipase is an enzyme found in intestinal mucosal cells that digests triacylglycerols to a mixture of free fatty acids, glycerol, monoacylglycerols, and diacylglycerols. The enzyme requires calcium and is unusual in catalyzing its reaction at an oil-water interface (Figure 18.6). 

Diacylglycerols (DAG) are found naturally as minor components in various dietary lipids. Although human adults ingest 1 to 5 g of DAG every day, little attention has been paid to its nutritional characteristics because DAG have been recognized only as intermediates in the process of TAG digestion and absorption. 

Digestion and Absorption of Diacylglycerol Teruyoshi Yanagita, and Ikuo Ikeda... 

The liver (hepatopancreas or digestive gland) of freshwater snails contains mainly free sterols, triacylglycerols, and sterol esters (Figure 15.3, lane 2). Additionally, diacylglycerols may also be detected. The study described here is based on unpublished observations in our laboratory on the TLC analysis of the common viviparid snail, Campeloma decisum, found in freshwater ponds in the United States. Similar experiments can be done with the hepatopancreas of other available marine or freshwater snails (see Chapter 4). For this experiment, obtain 100... 

Apart from the limited resolution of this procedure, it was not possible to assay small amounts of endogenous diacylglycerols and monoacylglycerols in plasma as these were masked by similar lipids derived from phospholipase C digestion of the phospholipids. A comparable automated procedure was therefore developed by the Czechoslovakian group in which the phospholipase C digestion step was omitted and only the simple lipids were assayed [595,596]. Here also the methodology has proved its worth in clinical trials [848,849] and in comparisons with alternative methods [593],... 

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