戴氏绿僵菌活性多糖深层发酵的培养基优化

戴氏绿僵菌是食药用虫草戴氏虫草的无性型，以其胞外多糖产量为指标，采用单因素试验与正交试验，对戴氏绿僵菌液体深层发酵培养基中的碳源、氮源、生长因子、无机盐进行优化。结果表明：利用优化后的培养基发酵，即木糖40g/L、黄豆浆4g/L、硫酸铵0.2g/L、VA+VD 1g/L、KH2PO4 1g/L、MgSO4·7H2O 0.5g/L初始pH6.0，胞外多糖的产量高达(22.72 ± 0.55)g/L，比发酵基础培养基产量增加30 多倍，也明显高于迄今已见报道的虫草相关真菌的胞外多糖产量。

Optimization of Culture Medium Composition for Active Polysaccharide Production from Metarhizium taii

Matarhizium taii, the anamorph of edible medicinal mushroom Cordyceps taii, can produce polysaccharide with diverse pharmacological effects for the development of functional foods and new drugs. The purpose of this study was to investigate the use of a combinatorial experimental strategy, involving both one-factor-at-a-time and orthogonal array design methods to optimize the fermentation medium composition for active polysaccharide production by submerged fermentation of Matarhizium taii. The results showed that the optimal medium composition for active polysaccharide production consisted of xylose 40 g/L, soybean steep liquor 4 g/L, (NH4)2SO4, 0.2 g/L vitamin A plus D 1 g/L, KH2PO4 1 g/L and MgSO4·7H2O 0.5 g/L at initial pH 6.0. Using such a medium, an exocellular polysaccharide yield of up to (22.72 ± 0.55) g/L was obtained, which was over 30 times higher than that obtained using fermentation basal medium.