裂褶菌多糖发酵培养基优化及其活性研究

以胞内总多糖产量为响应值，采用单因素试验与Box-Behnken响应面法优化裂褶菌产多糖的液态深层发酵培养基配方，并研究其抑菌、抗氧化及保湿活性。结果表明，最佳培养基配方为葡萄糖20 g/L、酵母浸粉29.5 g/L、KH2PO4 0.6 g/L、抗坏血酸0.006 g/L、β-环糊精17 g/L、谷氨酰胺0.000 5 g/L、透明质酸0.05 g/L、羧甲基淀粉钠3 g/L，采用最优培养基摇瓶发酵11 d，总多糖产量达5.35 g/L，10 L发酵罐发酵6 d，总多糖产量达6.39 g/L。10.0 mg/mL的裂褶菌多糖（SPG）对大肠杆菌、绿脓杆菌、枯草芽孢杆菌、金黄色葡萄球菌的抑菌率分别为56.24%、33.75%、32.62%和42.51%；2.0 mg/mL的SPG对O2-·、·OH、DPPH·和ABTS自由基的清除率分别为84.58%、15.08%、18.61%、32.60%；在相对湿度（RH）为43%和81%的环境中放置8 h，保湿率均＞98%；表明SPG具有较强的抑菌、抗氧化和保湿活性。

Optimization of fermentation medium of Schizophyllum commune and schizophyllan polysaccharide activity

Using the yield of total intercellular polysaccharide from Schizophyllum commune as response value, the medium formula for submerged fermentation of S. commune for polysaccharides production was optimized by single factor experiments and Box-Behnken response surface methodology, and the bacteriostatic activity, antioxidant activity and moisture retention were studied. The results indicated that the optimum medium formulation for intercellular polysaccharides yield of S. commune was as follows: glucose 20 g/L, yeast extract powder 29.5 g/L, KH2PO4 0.6 g/L, ascorbic acid 0.006 g/L, β-cyclodextrin 17 g/L, glutamine 0.000 5 g/L, hyaluronic acid 0.05 g/L and sodium carboxymethyl starch 3 g/L. After cultured for 11 d under the condition, the yield of total polysaccharides was 5.35 g/L with shaking flask. The yield of total polysaccharides in 10 L fermentor was 6.39 g/L for 6 d. The antibacterial rates of schizophyllan polysaccharide (SPG) 10.0 mg/ml on Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus were 56.24%, 33.75%, 32.62% and 42.51%, respectively. When the mass concentration of schizophyllan polysaccharide was 2.0 mg/ml, the scavenging rates for O2-·, ·OH, DPPH· and ABTS free radical were 84.58%, 15.08%, 18.61% and 32.60%, respectively. In the environment of relative humidity of 43% and 81% placed for 8 h, the moisturizing rate was up to 98%. The results indicated that the schizophyllan polysaccharide had stronger activity on bacteriostasis, antioxidation and moisture retention.