通过优化刺糖多孢菌发酵合成多杀菌素培养基成分,改善培养条件,从而提高多杀菌素产量.在单因 素以及Plackett-Bummn试验设计的基础上,采用Box-Behnken试验设计方法对发酵培养基组分中的玉米浆、可溶性 淀粉、丙酸钠进行研究,运用遗传算法优化的BP神经网络建立多杀菌素产量与培养基组分浓度之间的预测模型, 采用循环算法对此模型进行寻优,得到三种组分的最佳配比为玉米浆7 g/L、可溶性淀粉16 g/: L、丙酸钠2 g/L,多 杀菌素产量达到( 550.22 ± 3. 84) mg/L,采用上述方法优化后的培养基使得多杀菌素产量比原始培养基产量( 225 mg/L)提高145% .本研究结果可为培养基优化提供-种有效的建模方法.
In this work, we report an approach to improve spinosad production by optimizing the fermentation medium components. Com steep liquor, soluble starch and sodium propionate in the fermentation medium were in-vestigated by Box-Behnken design (BBD) , which was based on single factor and the Plackett-Burman design. Moreover, a prediction model of the spinosad yield as a function of the medium component concentration has been established by using the artificial neural network ( ANN) optimized by genetic algorithm ( GA) . Using ANN opti-mized by GA as the objective function, we employed the circulatory algorithm to optimize the medium components and the optimal ratio of the three components as follows: with com steep liquor 7 g/ L, soluble starch 16 g/L, and sodium propionate 2 g/L,the final yield of spinosad reached (550. 22 ± 3. 84 ) mg/L, which was 145% higher than the original fermentatiom medium(225 mg/L) obtained when cultured on the optimized medium. Our results from this study can provide an effective modeling method for medium optimization.