Response Surface Modeling of Lipase-Catalyzed Isoamyl Propionate Synthesis


  • The authors thank the Director, CFTRI, Mysore, for providing the facilities. Helpful suggestions from Dr. A.P. Sattur are acknowledged. S. Hari Krishna is thankful to the Council of Scientific and Industrial Research, New Delhi, India, for awarding his Senior Research Fellowship.


ABSTRACT: Response surface methodology based on a 3-variable, 5-level central composite rotatable design matrix was used to optimize the synthesis. The influence of selected variables, namely, enzyme/substrate (E/S) ratio, substrate concentration, and temperature was investigated. E/S ratio and temperature had a strong effect on esterification, while substrate concentration did not. Reaction time did not show significant effect on ester yields, and conversions could be completed in less than 24 h. The response surface model has been found to describe the experimental results adequately. Product yield at optimum conditions (24 g/mol E/S ratio, 1.5 M substrate concentration 20 °C) was 1.4 M, representing 93% conversion, which is in good agreement with the predicted one.