Zwitterionic polymer-coated porous poly(vinyl acetate-divinyl benzene) microsphere: A new support for enhanced performance of immobilized lipase

Enzyme immobilization has attracted great attention for improving the performance of enzymes in industrial applications. This work was designed to create a new support for Candida rugosa lipase (CRL) immobilization. A porous poly(vinyl acetate-divinyl benzene) microsphere coated by a zwitterionic polymer, poly( maleic anhydride-alt-1-octadecene) and N,N-dimethylethylenediamine derivative, was developed for CRL immobilization via hydrophobic binding. The catalytic activity, reaction kinetics, stabilities and reusability of the immobilized CRL were investigated. It demonstrated the success of the zwitterionic polymer coating and subsequent CRL immobilization on the porous microsphere. The immobilized lipase ( p2-MS-CRL) reached 27.6 mg.g(-1) dry carrier and displayed a specific activity 1.5 times higher than free CRL. The increase of V-max and decrease of K-m were also observed, indicating the improvement of catalytic activity and enzyme-substrate affinity of the immobilized lipase. Besides, p2-MS-CRL exhibited significantly enhanced thermal stability and pH tolerance. The improved performance was considered due to the interfacial activation regulated by the hydrophobic interaction and stabilization effect arisen by the zwitterionic polymer coating. This study has thus proved the advantages of the zwitterionic polymer-coated porous carrier for lipase immobilization and its potential for further development in various enzyme immobilizations. (C) 2019 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.