Kinetic study of asymmetric hydrolysis of dimethyl 3-(4-fluorophenyl) glutarate using novozym 435

Immobilized Candida antarctica lipase B (Novozym 435) was used to catalyze the asymmetric hydrolysis of dimethyl 3-(4-fluorophenyl)glutarate (3-DFG) in an aqueous system containing methyl tert-butyl ether (MTBE) as cosolvent. The present work put emphasis on the kinetic study of the asymmetric hydrolysis reaction. The effects of rotation speed, enzyme loading, concentrations of substrate and product on the reaction were investigated. The optimal rotation speed was 200 r·min^-1, and the reaction was free from intra-particle diffusion limitations. The inhibitions of substrate (3-DFG) and product (3-MFG) were excluded which both displayed no decline on the activity of Novozym 435 at elevated concentrations within the given range. In addition, methanol, a byproduct of the reaction, inhibited the activity of Novozym 435 following a competitive inhibition pattern. The kinetic constants were obtained through non-linear regression, with values of K_m 0.24 mol·L^-1, K_i 0.39 mol·L^-1, V_max 2.39 mmol·L^-1·h^-1, respectively.