羊肚菌胞外多糖液态发酵培养基配方优化及其体外降血糖活性

本研究以甘肃省野生三地羊肚菌为研究对象，探究羊肚菌胞外多糖液态发酵培养基最佳方案与体外降血糖活性。采用单因素实验比较红糖、玉米粉等7种添加物对羊肚菌液态发酵过程中胞外多糖含量的影响，在此基础上采用响应面分析法优化羊肚菌胞外多糖液态发酵培养基配方。通过测定羊肚菌胞外多糖对α-淀粉酶和α-葡萄糖苷酶抑制率检测其体外降血糖活性。结果表明:当红糖添加量2.20 g/L、尿素添加量3.18 g/L、玉米粉添加量2.40 g/L时，实际得到羊肚菌胞外多糖的含量可达到1.20 g/L。羊肚菌胞外多糖在浓度为1.0 mg/mL时对α-葡萄糖苷酶和α-淀粉酶的抑制率则分别达到73.46%和36.37%，羊肚菌胞外多糖具有较好的降血糖活性。

Optimization of Liquid Fermentation Medium Formulation of Morchella eohespera Exopolysaccharide and Its Hypoglycemic Activity in Vitro

In this study, strains of wild Morchella eohespera in Gansu province were selected as the research object to explore the optimal solution of liquid fermentation medium of M. eohespera extracellular polysaccharide and its hypoglycemic activity in vitro. A single factor experiments were conducted to compare the effects of seven additives, including brown sugar and corn meal, on the content of M. eohespera extracellular polysaccharide during liquid fermentation. On this basis, response surface methodology was used to optimize the liquid fermentation medium formula of M. eohespera exopolysaccharides. The hypoglycemic activities of extracellular polysaccharide from M. eohespera on α-amylase and α-glucosidase were determined in vitro. The results showed that when the amounts of addition of brown sugar was 2.20 g/L, urea was 3.18 g/L and corn flour was 2.40 g/L, the actual content of extracellular polysaccharide of M. eohespera could reach 1.20 g/L. At the concentration of 1.0 mg/mL, effects of extracellular polysaccharide of M. eohespera on α-glucosidase and α-amylase showed that the inhibition rates for these enzymes were 73.46% and 36.37%, respectively. The results showed that extracellular polysaccharide of M. eohespera was with hypoglycemic activity.