碱性木聚糖酶产生菌的筛选及培养基成分的优化

Isolation of Alkaline Xylanase Producing Strains and Optimalization of the Fermentative Culture Medium

通过集富培养、水解圈鉴定、酶活检测,从不同地点采集富含木聚糖的土样中初筛出10株木聚糖酶产生菌,选取酶活最高的Bacillussp.No.X-18菌株,进行单因素、双因素和培养基成分的综合优化试验。结果显示最佳培养基是:1.5%蔗糖、1%阿拉伯糖、0.37%NH4C l、0.37%酵母膏、0.5%K2HPO4、0.02%MgSO4.7H2O,pH 8.0,其木聚糖酶活力可达74.21 IU/mL。

Ten strains of bacteria with xylanase activity were isolated from the soil by enrichment cultivating and the method of assaying transparent zone and the bacterial strain of Bacillus sp. No. X-18,which could produced the highest enzymatic activity, was obtained. Xylanase fermentative culture medium for the Bacillus sp. No. X-18 strain was optimized. The results showed that the optimal medium composition conrained 1.5 % sucrose, 1% ambinose,0.37 % NH4 Cl,0.37 % yeast extract, 0.5 % K2 HPO4,0.02 % MgSO4·7H2O,pH 8.0, and the enzyme activity could reach 74.21 IU/mL in the medium.