糖化酶产生菌的分离·鉴定及其选育

目的]对糖化酶产生菌的分离、鉴定及其选育进行研究。方法]采用稀释涂布法,分离纯化糖化酶产生菌,通过形态学与生理生化特征进行初步鉴定,再利用紫外线、亚硝酸和聚六亚甲基胍对该菌进行复合诱变选育。结果]通过筛选获得1株产糖化酶野生株,其产酶活力为72.56 U/ml;经鉴定,该菌株为多粘芽孢杆菌(Bacillus polymyxa);选择紫外线、亚硝酸和聚六亚甲基胍(Polyhexamethy Leneguanidine hydroch Loride,PHMG)连续复合诱变后,突变株酶活力比出发菌株产酶量提高67.90%。结论]试验所筛选的多粘芽孢杆菌为糖化酶的生产提供了一个新的选择菌种。

Research on the Isolation, Identification and Selection of the Bacterium Strain Producing Glucoamylase

Objective] The isolation,identification and breeding of the bacterium strain producing glucoamylase was researched.Method] The diluted coating method was used in the isolation and purification of the bacterium strain producing glucoamylase.The morphology,the physiological and biochemical characteristics of the strain were preliminarily identified.The bacterium strain was bred by means of the compound treatment of ultraviolet light,nitrous acid and Polyhexamethy Leneguanidine hydroch Loride(PHMG).Results] A wild type of bacterium strain producing glucoamylase was screened,which activity was 72.56 U/ml,and the identification indicated the strain belonged to the Bacillus polymyxa.The activity of the enzyme of the mutant was 67.90% higher than that of initial strain after the compound treatment of ultraviolet light,nitrous acid and PHMG.Conclusion] The screen of the bacillus polymyxa strain provided the new approach of the glucoamylase production.