A Comparative Study Among Different Protocols of Immobilization of Dextranase Using Chitin as a Matrix

In the current research, second most abundant renewable polysaccharide chitin is utilized for meaningful purpose. Owing to auspicious features of chitin it is used as a matrix for immobilization of valuable biocatalyst dextranase. Dextranase belongs to hydrolase family and has broad commercial application in different fields. Functionality of dextranase is further improve with the help of its immobilization on chitin by different protocols. Dextranase used in this study was isolated from a thermophilic bacteria Bacillus megaterium KIBGE-IB31 explored from hydrothermal spring. Isolated dextranase was immobilized on chitin by two different methods namely; adsorption and covalent binding. A comparative study was conducted between soluble, adsorbed and covalently cross linked dextranase. It was observed that although, there was slight deviation in characteristics of dextranase after immobilization but there was marked improvement in stability of enzyme after immobilization. The comparative analysis revealed that dextranase immobilized by adsorption was less stable and fails to retained enzyme stability for increase reusability. The adsorption method was improved after treatment of chitin with acid and showed improved stability as well as reusability. However, dextranase immobilized by covalent cross linking displayed highest stability at high temperature along with increase recycling efficiency as compare to enzyme immobilized by adsorption method. Hence, it can be concluded that though chitin is cheap, easily accessible matrix for immobilization of dextranase but still among different protocols of immobilization covalent cross linking was found to be more appropriate in improving enzyme stability and its reusability at industrial scale.