Lipase-catalyzed hydrolysis of (+,-)-2-(4-methylphenyl) propionic methyl ester enhanced by hydroxypropyl-β-cyclodextrin

Abstract

BACKGROUND: Enzymatic kinetic resolution is an attractive technology for production of enantiomerically pure compounds. The objective of this research is to investigate the enantioselective hydrolysis of (+,-)-2-(4-methylphenyl) propionic methyl ester (2-(4-MP)PPAME) to (+)-2-(4-methylphenyl) propionic acid ((+)-2-(4-MP)PPA) catalyzed by enzyme in an aqueous medium. RESULTS: Lipase AY from candida rugosa (CRL) was screened as the best lipase. Novozym 435 IM and lipopan S BG show higher catalytic activity but the enantioselectivity is very low. By addition of hydroxypropyl-β-cyclodextrin (HP-β-CD) to the aqueous system, an increased substrate conversion of 45.28% was obtained, the high enantiomeric excess remaining compared with the conversion of 28.05% without HP-β-CD. Response surface methodology and central composite design were employed to model and optimize the reaction system. CONCLUSION: Under the optimal conditions including pH of 6.60, 12.5 mg mL−1 enzyme, 35 mmol L−1 HP-β-CD, 0.06 mmol substrate, temperature 39°C, agitation speed 400 rpm and 40 h reaction time, the substrate conversion was up to 40.32% and the optical purity of the product (+)-2-(4-methylphenyl) propionic acid was up to 95.22%. © 2018 Society of Chemical Industry.