交联壳聚糖微球固定化β-葡萄糖苷酶工艺研究

Study of the Immobilization of β-Glucosidase onto Cross-linked Chitosan Microsphere

目的:以戊二醛交联壳聚糖微球为载体,通过共价连接反应固定化β-葡萄糖苷酶。方法:以固定化酶比活和酶活回收率为目标,采用单因素方法优化固定化工艺、微球制备条件。结果:微球最佳制备条件:2.5%壳聚糖,2%乙酸,7.5%氢氧化钠,氢氧化钠:乙醇(v/v)=1∶1。最佳固定化工艺为:0.1g壳聚糖微球在20mL 3%戊二醛溶液中50℃交联2h。加酶量为7 388mU/g干球,25℃吸附24h。固定化酶比活为6 188mU/g干球,酶活回收率为95.4%。结论:交联壳聚糖微球共价连接法可有效固定化β-葡萄糖苷酶。

Objective： To optimize the immobilization of β- Glucosidase onto chitosan microsphere with glutaraldehyde. Method： Using activity of immobilized enzyme and activity recovery as response value, the effects of immobilization conditions and preparation conditions of cross - linked chitosan microsphere on immobilization were studied. Result：Tile optimal preparation conditions of chitosan microsphere were： 2.5 % chitosan, 2% acetic acid, 7.5% NaOH, the ratio of NaOH and ethonal（v/v） = 1 ： 1. The optimal immobilization conditions were as following： 0. lg wet chitosan microspheres was treated with 20mL 3% glutaraldehyde at 50℃ for 2h, then glucosidase was incubated with the microspheres for 24h at 25℃ with an enzyme loading of 7 388mU/g dry microspheres, giving the activity and activity recovery of the immobilized glucosidase 6188mU/g dry carrier and 95.4%, respectively. Conclusion： β- Glucosidase was immobilized by covalent bonding and the enzyme exhibited a considerable affinity to chitosan, giving high activity recovery while maintaining an optimum level of activity.