高温淀粉酶高产菌株筛选及产酶条件优化

为筛选高温淀粉酶高产菌株,利用淀粉酶水解圈作筛选模型,从稻田中采集土样,筛选得到产淀粉酶能力较高的菌株E10。为提高菌株产酶能力,进行了碳源种类及浓度,氮源种类及浓度,无机盐种类及浓度,pH值,种龄及接种量、温度、时间的单因素试验,并对发酵培养基及发酵条件进行了L9(34)正交优化试验。结果表明:最佳产酶发酵培养基为2.0%麸皮、0.1%硝酸钾、0.25%氯化钙,最适初始pH值为6.0。最适产酶条件为种龄24 h,接种量7 mL,于36℃下培养48 h。在优化条件下,菌株产酶活力可达180.94 IU/mL。

Screening of High-yield Strain Producing Thermostable Amylase and Optimization of Enzyme Production

In order to screen a high-yield strain producing thermostable amylase,starch hydrolysis circle was employed as a screening model. The E10 strain achieved from the paddy field soil has high capacity of enzyme production. In order to improve the capability of enzyme production of E10, the single factor experiments was conducted for the kinds and concentrations of carbon source,the kinds and concentrations of nitrogen source,the kinds and concentrations of inorganic salt,pH value,seed age,inoculate volume,temperature and time,then the L9(34) orthogonal optimization test for the fermentation medium and conditions was carried out. The results showed that the best fermentation medium of the enzyme production of E10 was 2.0% wheat bran,0.1% KNO3,0.25% CaCl2,initial pH value of 6.0. The optimal fermentation conditions of the enzyme production of E10 were 24 hours of seed age,7 mL of inoculates volume,36 ℃ of culture temperature,48 hours of time. Under the optimized conditions,the enzyme production of E10 reached 180.94 IU/mL.