Synthesis of triacylglycerol by lipase in phosphatidylcholine reverse micellar system

Triacylglycerols were synthesized from 1,2-diacylglycerol and fatty acids by lipase entrapped in phosphatidylcholine reverse micelles in n-hexane. In the reaction system without reverse micelles, however, 1,2-diacylglycerol was hydrolyzed into 2-monoacylglycerol and fatty acid, and triacylglycerol was not synthesized. The maximum activity of synthetic reaction was obtained at Wo=10 (Wo=mol water/mol surfactant), which was the water content of this reverse micellar system. Though the optimal pH of theR. delemar lipase reaction is about pH 5.6 in a bulk water system, the enzyme was active for triacylglycerol synthesis at pH’s from 5 to 9 in the reverse micellar system. For the synthesis of triacylglycerols, lauric, myristic, palmitic, stearic, oleic and arachidic acids were effectively used as the fatty acid substrate. 2-Monoacylglycerol was also effective as a substrate of triacylglycerol synthesis. Furthermore, 1,2-diacylglycerol could be replaced by several kinds of aliphatic alcohols as fatty acid acceptors in the reverse micellar system. In this case, those alcohols with chain length more than 4 carbons were effectively used for ester formation.