A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. The biosynthesis of triacylglycerol is localized to the endoplasmic reticulum membrane and starts with glycerol 3-phosphate reacting with acyl-CoA through a glycerol-3-phosphate O-acyltransferase resulting in the release of lysophosphatidic acid (LPA). This, in turn, reacts with an acyl-CoA through a lipase complex resulting in the release of CoA and phosphatidic acid. Phosphatidic acid reacts with water through a phosphatidic acid phosphohydrolase 1 resulting in the release of a phosphate and a diacylglycerol. This reaction can be reversed through a CTP-dependent diacylglycerol kinase. The diacylglycerol reacts in the endoplasmic reticulum with an acyl-CoA through a diacylglycerol O-acyltransferase resulting in the release of coenzyme A and a triacylglycerol. Triacylglycerol metabolism begins with a reaction with water through lipase resulting in the release of a fatty acid, hydrogen ion, and a diacylglycerol. Diacylglycerol then reacts with a lipase 3 resulting in the release of a fatty acid and a monoacylglycerol. Monoacylglycerol reacts with monoglyceride lipase resulting in the release of a fatty acid in glycerol.

Triacylglycerol Metabolism TG(15:0/18:0/20:0) References