统计学分析方法应用于富硒米曲霉发酵培养基的优化

Optimization of medium for cul turing selenium-enriched aspergillus oryzae by statistical method

应用Plackett-Burman设计法对影响富硒米曲霉发酵的培养基组分进行了筛选,所选的6个相关因素为:蔗糖、酵母膏、氯化钙、硫酸镁、磷酸二氢钾和VB1。确定影响富硒米曲霉发酵的关键因素为:氯化钙、酵母膏和VB1。应用最陡爬坡实验逼近以上3个因素的最大响应区域。在此基础上,采用中心组合设计结合响应面法(Response Surface Methodology,RSM)对影响富硒米曲霉富硒发酵的关键因子的范围进行进一步确定,主要影响因素的最佳浓度为氯化钙0.25 g/L,酵母膏28.4 g/L,VB10.015 g/L。验证实验结果表明,采用优化后的培养基,米曲霉的胞内硒含量达到2.268 mg/g,与理论值相差1.4%。因此,利用响应面法对米曲霉富硒的培养基进行优化合理可行。

The medium components for culturing selenium-enriched aspergillus oryzae were optimized by statistical method. First, the effects of six factors including sucrose, yeast extract, CaCl2, MgSO4 · 7H2O, KH2PO4 and VB1 were evaluated by Plackett-Burman design. CaCl2, yeast extract and VB1 showed the significant effects. Subsequently, the fermentation condition was approached by the design of steepest ascent, and then a three-level three-factor central composite design was employed to optimize the concentration of CaCl2, yeast extract and VB1. At last, the three optimal parameters were determined as 0.25 g/L CaCl2, 28.4 g/L yeast extract and 0.015 g/L VB1,while the content of selenium was 2.268 mg/g.