TRANSESTERIFICATION KINETICS OF TRIGLYCERIDES FOR A MODIFIED LIPASE IN N-HEXANE

A simple kinetic model for the transesterification of triglycerides catalyzed by a modified lipase in n-hexane has been proposed. The model assumes that the enzyme has 1,3-positional specificity and does not distinguish among the different fatty acid residues considered in this study. The model is based on material balances of consecutive second-order reversible reactions and requires only one parameter that can easily be determined experimentally. The differential rate equations have been solved analytically to give explicit equations that link the concentrations of all possible triglycerides to the initial conditions and the reaction time. The model was in good agreement with experimental data for different biocatalyst concentrations with the same value of the specific rate constant. The same value of specific rate constant also gave a good fit with experimental data for an acidolysis reaction between a triglyceride and a fatty acid, implying that the modified lipase did not distinguish between free fatty acids and fatty acid residues attached to the 1 and 3 positions of a glycerol backbone.