具杀螺活性的商陆根际真菌Aspergillus fumigatus SL-30发酵条件优化

Optimization of Fermentation Conditions for Molluscicidal Rhizosphere Fungi Aspergillus fumigatus from Phytolacca acinosa Roxb.

以杀螺率为响应值,对商陆根际真菌菌株SL-30的发酵条件进行优化。在前期单因素试验的基础上,采用Plackett-Burman设计法,对影响菌株发酵滤液杀螺活性的主要因素进行筛选,确定了三个主要因素依次为可溶性淀粉,蛋白胨和初始pH。采用响应面分析法确定了以上三个显著因子的最佳水平分别及交互影响,结果显示,三个显著因素的最佳水平为可溶性淀粉16.40 g/L,蛋白胨3.76 g/L,初始pH 3,该条件下发酵滤液的杀螺活性预测值达98.949%。经六批次的发酵验证,预测值与试验平均值接近。

Fermentation conditions of a rhizospheric strain named as SL-30 from Phytolacca acinosa Roxb.were optimized.On the basis of early study,Plackett-Burman design was undertaken to evaluate the effects of the eight factors and three statistically significant parameters including soluble starch,peptone and initial pH were selected.Then a response surface methodology was used to optimize the above three factors,and to find out the optimal concentration levels and the relationships between each pair of these factors.The result showed,under conditions of soluble starch 16.40 g/L,peptone 3.76 g/L and initial pH 3 the molluscicidal activity of fermentation broth＇s filtrate reached 98.949%.After six batches cultivation,the predicted values were verified by validation experiments.