ImmobilizedCandida 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 methyltert-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 ofKm0.24 mol⋅L−1,Ki 0.39 mol⋅L−1,Vmax2.39 mmol⋅L−1⋅h−1 , respectively.%对 Novozym 435在以甲基叔丁基醚(MTBE)为助溶剂的水相体系中不对称水解3-(4-氟苯基)-戊二酸二甲酯(3-DFG)的动力学进行了研究。考察了摇床转速、酶浓度、底物浓度、产物浓度等因素对该水解反应的影响。结果表明该水解反应的最佳转速为200 r⋅min−1,内扩散的影响可忽略。底物3-(4-氟苯基)-戊二酸二甲酯和产物3-(4-氟苯基)-戊二酸单甲酯(3-MFG)对Novozym 435的催化水解活性不存在抑制作用。此外,该反应受副产物甲醇的竞争性抑制,通过非线性回归求得该体系相应的动力学参数值:米氏常数Km值为0.24 mol⋅L−1,抑制常数Ki值为0.39 mol⋅L−1,最大反应速度Vmax值为2.39 mmol⋅L−1⋅h−1。
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