固定化Bacillus thuringiensis ZJOU-010壳聚糖酶的研究  

Immobilization and Enzymatic Properties of Chitosanase from Bacillus thuringiensis ZJOU-010

作　　者：陈静[1] 陈余 鹿刘奇[1] 陈小娥[1] 方旭波[1] 

机构地区：[1]浙江海洋学院食品与药学学院、医学院,浙江舟山316000 [2]乐清市乐成镇农业综合服务中心,浙江乐清325600

出　　处：《食品科学》2010年第23期326-330,共5页Food Science

基　　金：浙江省自然科学基金项目(Y305119);浙江省优先主题农业项目(2008C12029);2009年浙江省大学生科技创新活动计划(新苗人才计划)项目

摘　　要：采用吸附交联技术,以DEAE-22纤维素为载体、戊二醛为交联剂,固定Bacillus thuringiensis ZJOU-010壳聚糖酶,考察固定化酶的制备条件,并研究固定化酶的性质。结果表明B.thuringiensis ZJOU-010壳聚糖酶的最佳固定化条件为:戊二醛体积分数3.0%、加酶量20mg、固定化时间10h;在此条件下制备的固定化壳聚糖酶的最适pH值和温度分别为4.83和50℃;与游离酶相比,该固定化酶的热稳定性较好,在40℃和50℃条件下的半衰期(t1/2)分别为36.3h和6.2h,动力学常数Km值为9.19g/L;该固定化酶重复使用10批后活力仍可保持初始活力的88.32%。The chitosanase in the fermentation broth of B.thuringiensis ZJOU-010 was immobilized by adsorption onto DEAE-22 cellulose and cross-linking with glutaraldehyde. The immobilization conditions of this enzyme were investigated. Apart from this, its enzymatic properties after the immobilization were characterized. The optimal enzyme immobilization process determined was that the immobilization was allowed to proceed for 10 h under the conditions of 3.0% glutaraldehyde concentration and 20 mg enzyme loading. The optimal pH and temperature of the immobilized enzyme obtained under these conditions were 4.83 and 50 ℃, respectively. It had better thermostability than its free counterpart, displaying half-lives of 36.3 h at 40 ℃ and 6.2 h at 50 ℃ and a kinetic parameter Km of 9.19 g/L. After being repeatedly used for 10 times, the residual activity of the immobilized enzyme as percentage of original activity was 88.32%.

关 键 词：壳聚糖 壳聚糖酶 固定化 吸附交联 DEAE-22纤维素 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]