从土壤中快速筛选葡萄糖氧化酶产生菌及发酵工艺的优化

Screening of Glucose Oxidase Producing Strain from Soil and Study on the Enzyme Producing Conditions

目的:从土壤中筛选葡萄糖氧化酶产生菌,并通过对其产酶特性研究及工艺优化提高其产酶量,为下一步育种工作打下良好基础。方法:采用Fiedure K.J.显色法从土壤样品中分离葡萄糖氧化酶产生菌,通过均匀设计等方法对培养基和发酵条件进行优化。结果:获得一株葡萄糖氧化酶产生菌L7。经优化后的培养基成分(g.L-1)为:葡萄糖60,蔗糖40,蛋白胨6,NaNO37,KH2PO40.5,Mg2SO4.7H2O1.1,KCl0.8,CaCO33.5。最适发酵条件为发酵温度26℃,消前pH值6.0,摇床转速250r.min-1,发酵周期3d。结论:从土壤中筛选到一株葡萄糖氧化酶产生菌L7,经过条件优化后酶活可达到2.56μmol.min-1。

Objective： It was to screening a glucose oxidase producing strain. Oxidase producing characteristic of the strain was studied and technics was optimized to increase field of oxidase, which may build the good foundation for the next step of breeding work. Methods： Fiedure. K.J. colour developing method was adoppted to isolate and screen the glucose oxidase producing strain from soil. The optimum medium ingredients and fermentation conditions were determined by using uniform design in this study.Results： A glucose oxidase producing strain was obtained.The rusults suggested that the optimal medium contained（g/L） glucose 60, sucrose 40,peptone 6, NaNO3 7, KH2PO4 0.5,Mg2SO4 ·7H2O 1.1,KCl 0.8, CaCO3 3.5. The ertzyrae activity of the strain amounted to 2.56μmol/min at 26℃ in 3 days under the optimal medium by shaking flask,which increased by 3.08 times contrasted to the initial.The speed of shaking table was 250r/min, and the value of initial pH was 6.0. From the experimentation we also found that the grade of the strain fragmentation and the time cost on enzyme activity mensurating would affect the enzyme activity. Conclusion： A glucose oxidase producing strain named L7 belongs to Aspergillus niger was obtained. The enzyme activity of the strain amounted to 2.56μmol/min under the optimal medium.