生防解淀粉芽孢杆菌CC09合成iturin A条件的响应面优化

Optimization of Iturin A Synthesis by Bacillus amyloliquefaciens CC09 Using Response Surface Technique

采用摇瓶发酵试验,比较了11种已用于芽孢杆菌合成环脂肽的培养基对解淀粉芽孢杆菌CC09产iturin A的影响,筛选适合菌株CC09产iturin A的主要营养成分。然后采用Plackett-Burman设计、中心组合设计和响应面分析等方法,优化培养基组成及发酵条件。获得了解淀粉芽孢杆菌CC09摇瓶发酵产生iturin A的最佳培养基组成为小麦粉14 g/L、黄豆饼粉25 g/L、玉米粉8 g/L、MgSO_4 0.1 g/L、MnSO_4 2.5 mg/L、FeSO_4 0.8 mg/L;最佳发酵条件为装液量60 mL/250 mL、pH 6.0、28℃、125 r/min、48 h,在此条件下,生防解淀粉芽孢杆菌CC09合成iturin A的产量达501 mg/L,较优化前的138 mg/L提高了4.2倍,且发酵成本是利用改良LB培养基的4.3%。

By shaking flask-fermentation assay, we compared the effects of 11 media commonly used for the cycle lipopeptide production by Bacillus spp. on the Iturin A synthesis of strain CC09, and optimized fermentation conditions by using the Plackett-Burman method, the central composite design and the response surface techniques. Results showed that CC09 could produce Iturin A up to 501 mg/L under the optimal medium： wheat powder 14 g/L, soybean meal 25 g/L, corn flour 8 g/L, MgSO_4 0.1 g/L, MnSO_4 2.5 mg/L, FeSO_4 0.8 mg/L; and culture condition： 60 mL medium in 250 mL flask, pH 6, 28 ℃, 125 r/min, 48 h. Under the optimized condition, the production of Iturin A by strain CC09 is 4.2-fold higher than that by the strain fermented in LB medium（138 mg/L）. Moreover, the fermentation cost under the optimal condition is about 4.9% of the cost under the modified LB medium.