Lipase catalyzed transesterification of ethyl butyrate synthesis in n-hexane- a kinetic study.

Abstract

Kinetics of lipase catalyzed transesterification of ethyl caprate and butyric acid was investigated. The objective of this work was to propose a reaction mechanism and develop a rate equation for the synthesis of ethyl butyrate by transesterification using surfactant coated lipase from Candida rugosa. The reaction rate could be described in terms of Michaelis-Menten equation with a Ping-Pong Bi-Bi mechanism and competitive inhibition by both the substrates. The values of kinetic parameters computed were Vmax=2.861μmol/min/mg; Km(acid)=0.0746M; Km(ester)=0.125M; Ki acid=0.450M. This study indicated a competitive enzyme inhibition by butyric acid during lipase catalyzed transesterification reaction. Experimental observations had clearly indicated that the substrates as well as product act as dead-end inhibitors.