核桃内生细菌Bacillus subtilis HB1310发酵棉秆水解糖液产油工艺优化

Optimization of lipid production technology by a walnut endophytic Bacillus subtilis HB1310 using cotton stalk hydrolysate as substrate

为实现核桃内生产油细菌Bacillus subtilis HB1310发酵棉秆水解糖液高效生产微生物油脂,检测了糖液浓度、氮源浓度、发酵起始p H值以及发酵时间4个主要因素对该菌株发酵棉秆水解糖液产油率的影响。通过单因素试验确定了响应面试验中各因素的水平中心点。通过响应面试验确定了菌株发酵棉秆水解糖液产油的优化工艺参数为糖液浓度7%(w/v)、氮源浓度5 g/L、发酵起始p H值6.0、发酵时间2 d,在此优化工艺条件下进行验证试验,获得的产油率可达30.26%±1.05%(w/w),与模型的理论预测值较接近,说明建立的模型是切实可行的。

In order to improve the lipid production technology by a walnut endophytic Bacillus subtilis HB1310 using cotton stalk hydrolysate as substrate, the effects of reducing sugar concentration,nitrogen source concentration, initial p H value and fermentation time on lipid content production were examined. The results showed that the central points of four factors in Response surface experiment were determined by the single factor experiments. The optimal technical parameters were determined by response surface experiment as follows： reducing sugar concentration was 7%（w/v）, nitrogen concentration was 5 g/L, initial p H value was 6.0, fermentation time was 2 d,the validating experiment under the optimized fermentation conditions was developed,the experimental value can be reached30.26%±1.05%（w/w）, which was close to the theoretical predicting value,indicating that the model was feasible.