响应面法优化促植物生长枯草芽孢杆菌CK15产芽孢条件

目的]优化枯草芽孢杆菌CK15的发酵条件,提高其芽孢产量。方法]通过单因素试验优化碳源种类及浓度、氮源种类及浓度、无机盐种类、装液量、摇床转速、初始p H、温度、接种量,采用Plackett-Burman试验筛选出培养基中的显著因素,再利用Box-Behnken试验确定3个因素的最佳浓度。结果]在玉米粉10.7 g/L、豆粕粉24.4 g/L、CaCO_3 7.4 g/L、NaCl 5.0 g/L、MnSO_4　0.4 g/L、KH_2PO_4　1.0 g/L、装液量50 m L/250 m L、转速为200 r/min、初始p H 7.2、温度30℃、接种量2.0%条件下,芽孢产量达到7.4×109cfu/m L,比优化前提高了80.49%。结论]响应面法有效提高了枯草芽孢杆菌CK15的芽孢产量。

Optimization of Fermentation Condition for Spore Production of Plant Growth Promoter Bacillus subtilis CK15 by Response Surface Methodology

Objective] To optimize the fermentation condition of Bacillus subtilis CK15 and to enhance the Spore Production yield. Method] Single factor test was used to optimize the type and concentration of carbon source, type and concentration of nitrogen source, the type of inor-ganic salt, loaded liquid volume, shaker speed, initial pH, temperature and inoculum size.The optimal concentrations of three factors were determined by Plackett-Burman design; and the optimal concentrations of three factors were obtained by Box-Behnken test. Result] The spore production was 7.4 ×109 cfu/mL under the conditions of 10.7 g/L corn flour, 24.4 g/L soybean meal powder, 7.4 g/L CaCO3 , 5 g/L NaCl, 0.4 g/L MnSO4 , 1.0 g/L KH2 PO4 , 50 mL/250 mL loaded liquid volume, 200 r/min rotation speed, initial pH 7.2, 30 ℃ tempera-ture, and 2 %inoculation amount.Thus, the spore production increased by 80.49%than before.Conclusion] The response surface method effectively improves the spore production of Bacillus subtilis CK15.