Production and Kinetics of Isoamyl Acetate from Acetic Anhydride using Candida Antarctica Lipase B in a Solvent-Free System

Abstract

Isoamyl acetate is the most essential esters in food industry. Studies on isoamyl acetate production were expanded since 1976 through having 1174 patents that contains isoamyl acetate on that year. Most researches have used hexane or heptanes as solvent which are not preferable due to their toxic properties. Therefore, the risk and unfavorable conditions were removed by introducing solvent-free system. In this study, isoamyl acetate was produced using Candida Antarctica Lipase-B (CALB) by esterification reaction between acetic anhydride and isoamyl alcohol in a solvent-free system. The parameters studied were acid-alcohol molar ratio (0.1 – 2), reaction time (2-6 h), temperature (30-50 °C) and mass of enzyme (4-12 wt%). The isoamyl acetate production was maximum (41.6-fold) at acid to alcohol molar ratio of 2, mass of enzyme of 5.78 wt%, at time of 3 h and 44 °C reaction temperature. An enzymatic kinetic model based on modified Michaelis-Menten equation was developed and fitted to the non-linear regression to the experimental data. The model developed was in agreement with the experimental data with R2 value equals to 0.999.