Studies of poly(vinyl acetate-co-diviyl benzene) beads as a carrier for the immobilization of penicillin acylase and the kinetics of immobilized penicillin acylase

Abstract

Poly(vinyl acetate-co-diviyl benzene) beads were synthesized via a novel polymerization method. The amount of hydroxide radical could reach 11.5 mmol g −1 (wet) after the beads were catalyzed by NaOH in methanol at 18–20°C for 24 h. The activators such as SESA, glutaraldehyde and p-benzoquinone were used to immobilize penicillin acylase. The penicillin acylase immobilized with SESA exhibited better stability than that with other activators. The successively immobilization could increase the activity of immobilized penicillin acylase about two times and the activity yield 10%, respectively. At the optimal conditions of immobilization, the activity of immobilized penicillin acylase amounted to 812–1200 unit per gram (wet). The kinetics of immobilized penicillin acylase was also studied. The reaction constants, K m , K iPAA , K iAPA and K s for immobilized penicillin acylase were equal to 0.033, 0.013, 0.009 and 0.081 mmol/ml, respectively.