Immobilization of a protease on modified chitosan beads for the depolymerization of chitosan |
| |
Authors: | Jin Li Jun CaiLian Zhong Yumin Du |
| |
Institution: | a Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China b Key Laboratory of Fermentation Engineering, Ministry of Education, Hubei University of Technology, Wuhan 430068, China c College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China d College of Resource and Environmental Science, Wuhan University, Wuhan 430072, China |
| |
Abstract: | Neutral protease was immobilized on chitosan (CS), carboxymethyl chitosan (CMCS), and N-succinyl chitosan (NSCS) hydrogel beads. And the biocatalysts obtained were used to prepare low molecular weight chitosan (LMWC) and chitooligomers. Weight-average molecular weight of LMWC produced by neutral protease immobilized on CS, CMCS and NSCS hydrogel beads were 3.4 kDa, 3.2 kDa and 1.9 kDa, respectively. The effects of immobilization support and substrate on enzymatic reaction were analyzed by measuring classical Michaelis-Menten kinetic parameters. The FT-IR, XRD and potentiometric determination results indicated decrease of molecular weight led to transformation of crystal structure, but the degree of N-deacetylation and chemical structures of residues were not changed compared to initial chitosan. The degree of polymerization of chitooligomers was mainly from 2 to 7. We observed a strong dependence of the immobilized enzyme properties on the chemical nature of the supports, which leads to different microenvironment of neutral protease and changes the hydrolyzing process. |
| |
Keywords: | Degradation Enzymes Low molecular weight chitosan Immobilization Characterization |
本文献已被 ScienceDirect 等数据库收录! |
|