利用响应面法对柳小皮伞液体发酵培养基的优化

首先采用Plackett-Burman设计对影响柳小皮伞(Marasmiussalicicola)AS5.166发酵胞外多糖培养基的组成成分进行了筛选,所选取的10个相关因素为:葡萄糖、蔗糖、酵母膏、蛋白胨、K2HPO4、KH2PO4、CaCl2、FeSO4、MgSO4、VB1。在此基础上,再采用响应曲面法(ResponseSurfaceMethodology,RSM)对影响柳小皮伞发酵胞外多糖培养基的关键影响因素蔗糖、酵母膏和FeSO4的最佳水平范围作了进一步的研究与探讨,通过对二次多项回归方程求解得知,在上述自变量分别为蔗糖23.28g/L、酵母膏12.21g/L和FeSO447.80mg/L时,胞外多糖产量的最大预测值为94.74mg/100ml。

Optimization of Cultivation Conditions for Extracellular Polysaccharide by Marasmius salicicola Using Response Surface Methodology

Our previous work has indicated that cultivation conditions for extracellular polysaccharide by Marasmius salicicola are strongly affected by many internal and external factors. In this study, we use an effective two-phase statistical approach to enhance extracellular polysaccharide production. In the first phase, Plackett-Burman design was undertaken to evaluate the effects of the ten factors, including glucose, sugar, yeast extract, peptone, MgSO4, KH2PO4, K2HPO4, FeSO4, CaCl2 and VB1. By regression analysis, glucose, sugar, yeast extract, KH2PO4, MgSO4 and FeSO4 were found to be important for cultivation conditions for extracellular polysaccharide by Marasmius salicicola. In the second phase of the optimization process, a response surface methodology (RSM) was used to optimize the above critical factors, and to find out the optimal concentration levels and the relationships between these factors. Based on the results of the first phase, a three-level three-factor (sugar, yeast extract, FeSO4) Box-Behnken design was employed. By solving the quadratic regression model equation using appropriate statistic methods, the optimal concentrations for obtain 94.74mg/100ml. Extracellular polysaccharide production was calculated as: 23.28g/L sugar, 12.21g/L yeast extract and 47.80mg/L FeSO4. The experimental data under various conditions have validated the theoretical values.