响应面法优化蛹虫草液体发酵配方及条件的研究

Optimization of formula and conditions for liquid fermentation of Cordyceps militaris by response surface method

蛹虫草是一种珍稀的药食两用真菌,为提高其菌丝体的液体发酵效率,首先通过单因素试验确定了蛹虫草液体发酵的最优碳源、氮源及适宜培养的pH、温度、装液量和转速6个因素。然后采用Plackett-Burman试验设计,确定葡萄糖、牛肉膏、温度是影响蛹虫草液体发酵菌丝体生物量的关键因素。利用响应面法设计三因素三水平试验,最终获得蛹虫草菌丝体液体发酵的最佳配方及条件为:牛肉膏13.34g/L、葡萄糖20.00g/L、MgSO41.5 g/L、KH2PO41.5 g/L,pH 6.5,摇床转速150 r/min,温度27℃。验证试验表明,优化后条件培养的菌丝生物量可达1.489 g/105 mL,是优化前的2倍,与模型预测值基本一致,优化效果较好,可为蛹虫草液体深层发酵培养及后续工厂化生产提供技术参考。

Cordyceps militaris is a kind of rare medicinal and edible mushroom.In order to improve the liquid fermentation efficiency of its mycelia,the optimum carbon source,nitrogen source,pH,temperature,volume of culture media and rotation speed for liquid fermentation were optimized by single factor test.Then Plackett-Burman method was used to further optimize the single factors that were screened to affect mycelia biomass to screen the key influencing factors.The optimal formula and conditions of liquid fermentation of C.militaris mycelia were obtained as follows:beef extract 13.34 g/L,glucose 20.00 g/L,MgSO41.5 g/L,KH2PO41.5 g/L,pH 6.5,shaking speed 150 r/min,temperature 27℃.Verification tests showed that the biomass of mycelia under optimized conditionscould reach 1.489 g/105 mL,which was twice that before optimization,basically consistent with the predicted value of the model,and the optimization effect was good,which provided a theoretical basis for liquid deep fermentation culture and subsequent factory production of C.militaris.