液体培养的桑黄胞外多糖发酵培养基成分的优化

摘要

通过27-3IV部分因子设计（FFD）,对葡萄糖、蛋白胨、酵母膏、磷酸二氢钾、硫酸镁、VB1以及草酸铵7个营养因子进行筛选。在此基础上,采用中心组合设计对部分因子设计,筛选出对桑黄胞外多糖产量的关键因子,确定培养基的组成和水平。在葡萄糖34.12g/L、酵母膏5.01g/L、蛋白胨4g/L、MgSO40.75g/L、KH2PO41g/L、VB10.0075g/L、草酸铵0.88g/L的条件下进行5次平行发酵实验。结果发现桑黄胞外多糖平均产量为（2.363±0.04）g/L,与预测值（2.342g/L）基本相符。可见,用该回归模型优化产桑黄胞外多糖的发酵培养基是可行的。%A 27-3IV fractional factorial design（FFD） was employed to determine culture medium ingredients affecting extracellular polysaccharide（EPS） production by P.baumii Pilát,such as glucose,peptone,yeast extract,ammonium oxalate,KH2PO4,MgSO4 and thiamine（VB1）.Glucose,yeast extract and ammonium oxalate were identified as key affecting factors,and their optimal levels were further investigated by means of a central composite design.The average EPS yield from 5 parallel fermentation experiments carried out using a culture medium（g/L） composed of glucose 34.12,yeast extract 5.01,peptone 4,MgSO4 0.75,KH2PO4 1,VB1 0.0075 and ammonium oxalate 0.88 was（2.363 ± 0.04）g/L,which was in substantial agreement with the predicted value（2.342 g/L）.It can be seen clearly that the developed regression model is applicable for the optimization of culture medium for EPS production.