Preparation of a novel nanobiocatalyst by immobilizing penicillin acylase onto magnetic nanocrystalline cellulose and its use for efficient synthesis of cefaclor

Abstract

Magnetic nanocrystalline cellulose (MNCC) was prepared and used as an enzyme support for the immobilization of penicillin acylase (PA). A novel coupling agent, tri(hydroxymethyl)phosphine(THP) instead of the conventional glutaraldehyde(GA), was used as a crosslinker in this study. The obtained results showed that the immobilized PA with THP (PA-THP-MNCC) had high enzyme loading (172.3 mg/g) and activity recovery (77.6%) in the optimal preparation conditions, which were remarkably superior to those of the counterpart using GA (PA-GA-MNCC, 148.4 mg/g and 48.7%, respectively). Compared with free PA and PA-GA-MNCC, PA-THP-MNCC displayed a higher optimum pH and temperature, and manifested relatively higher enzyme-substrate affinity and catalytic efficiency. In addition, PA-THP-MNCC exhibited significantly enhanced stability. Furthermore, PA-THP-MNCC was successfully employed for synthesis of cefaclor, an important second-generation cephalosporin antibiotic, affording a significantly higher yield of 84% than that reported previously.