银耳芽孢多糖发酵培养基配方、发酵条件的优化及其放大发酵试验

为开发银耳芽孢高产胞外多糖深层液态发酵培养基，提高银耳芽孢多糖的发酵产量以及实现规模化生产应用，本研究采用单因素实验探索不同来源的碳氮源及营养元素对银耳多糖产量的影响，并结合Plackett-Burman和Box-Behnken响应面设计，得到高产胞外多糖的发酵培养基配方和发酵条件，进一步使用50 L发酵罐进行了发酵工艺的验证。结果表明:优化后得到银耳芽孢高产胞外多糖发酵培养基配方为:葡萄糖35 g/L，NaCl 0.6 g/L，复合氮源（酵母浸膏和玉米浆干粉1:1）3.6 g/L，MgSO₄ 0.5 g/L，KH₂PO₄ 1 g/L；最适发酵条件为:发酵温度27 ℃，发酵初始pH5，发酵时间6 d，接种量3%（v/v），摇床转速150 r/min。优化完后银耳芽孢胞外多糖产量为214.45 mg/100 mL，在摇瓶发酵阶段达到了较高的产量水平。50 L发酵罐放大发酵中验证多糖得率为258.78 mg/100 mL，比摇瓶实验得率提高了21.03%。本次优化显著促进了银耳芽孢胞外多糖的产量，为其规模化工业生产提供理论支持。

Optimization of Fermentation Medium Formula and Fermentation Conditions of Tremella fuciformis Spore Polysaccharide and Its Scale-up Fermentation Experiment

In order to develop a submerged fermentation medium for high-yield extracellular polysaccharides (EPS) of Tremella fuciformis spore, to improve its fermentation yield and achieve large-scale production applications, this study used a single factor method to explore the effects of different sources of carbon and nitrogen sources and nutrient elements on the yield of Tremella polysaccharides. Through the Plackett-Burman and Box-Behnken response surface design to obtain the high-yield EPS fermentation medium and fermentation conditions, and verified the optimization results in a 50 L fermentation tank. The results showed that the fermentation medium of Tremella spores with high production of extracellular polysaccharides was: Glucose 35 g/L, NaCl 0.6 g/L, compound nitrogen source (yeast extracts:corn steep dry powder=1:1) 3.6 g/L, MgSO₄ 0.5 g/L, KH₂PO₄ 1 g/L; Optimal fermentation conditions were: 27 ℃, pH5, fermentation for 6 days, inoculation amount 3%(v/v) and shaker speed 150 r/min. After optimization, the yield of extracellular polysaccharide from Tremella spore was 214.45 mg/100 mL, with 8.56 times of that before optimization. In the 50 L fermentation tank, the polysaccharide yield was 258.78 mg/100 mL with 21.03% higher than the shake flask experiment. This optimization of the fermentation process significantly promoted the production of extracellular polysaccharides from Tremella spore, which would provide a theoretical support for its large-scale industrial production.