Efficient Resolution of cis-(+/-)-Dimethyl 1-Acetylpiperidine-2,3-dicarboxylate by Covalently Immobilized Mutant Candida antarctica Lipase B in Batch and Semicontinuous Modes

摘要

Candida antarctica lipase B (CALB) is a robust biocatalyst for production of chemicals. In this study, an engineered lipase B (CALB-I189K) was covalently immobilized onto a glutaraldehyde activated amino resin (ESR-3) and used for the preparation of chiral moxifloxacin precursor though enzymatic resolution of cis-(+/-)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate (cis-(+/-)-1). The immobilization conditions were optimized, and the immobilized CALB-I189K exhibited improved thermal stability, with a half-life of 247.5 h at 30 degrees C. It enables the resolution of 100 g L-1, cis-(+/-)-1 for 50 cycles in a stirred tank reactor, with an average productivity of 49.6 g L(-1)h(-1). The resolution reaction was also performed in a recirculating packed bed reactor (RPBR) in a semicontinuous mode, and the average productivity reached 59.4 g L(-1)h(-1) under the optimal operating condition. Moreover, the RPBR bioconversion system has high operational stability and conserved over 85.7% of the initial conversion capacity after 50 cycles. This efficient bioconversion process demonstrated the potential of employing immobilized CALB-I189K for industrial production of chiral moxifloxacin precursor.