本文以云南昆明石林地区的桑木耳为原料，优化了桑木耳多糖水提工艺，并对多糖的益生活性和体外抗氧化活性进行分析。通过单因素试验结合响应面法获得了优化的桑木耳多糖水提工艺为：在料液比1:108（m/V），提取温度100 ℃，提取时间3.5 h时，单次提取率达6.96%，经10次重复提取，多糖总得率高达34.18%。经凝胶色谱柱测定桑木耳多糖的重均分子量为2.09×107 u。采用离子色谱对桑木耳多糖的单糖组成进行分析，发现其主要单糖组分为葡萄糖，木糖和甘露糖，摩尔质量比为1.18:0.65:2.88。红外光谱结果显示，该多糖含有β型吡喃糖苷键。益生活性和抗氧化活性研究表明，桑木耳多糖可有效促进两歧双歧杆菌和青春双歧杆菌的增殖，并具有良好的ABTS自由基和羟自由基清除能力。桑木耳多糖浓度为10 mg/mL时，对ABTS自由基、羟基自由基的清除率分别达到98.93%和71.28%。

The extraction process of of Mulberry fungus polysaccharide (MFP) sampled from Kunming, Yunnan Province, were optimized and the probiotic and antioxidant activities of the extracted polysaccharides were analyzed in this study. By single factor test combined with response surface methodology, the optimized water extraction conditions of MFP were obtained. When the extraction was performed with the solid-liquid ratio of 1:108 (m/V) at 100℃ for 3.5 h, the polysaccharide yield was 6.96%. After 10 repeated extractions, the polysaccharide yield was as high as 34.18%. High performance gel permeation chromatography (HPGPC) analysis showed the average molecular weight of MFP was 2.09×107 u. The monosaccharide composition analyzed by ion chromatography showed that MFP mainly contained glucose, xylose and mannose, their molar mass ratio was 1.18: 0.65: 2.88. Fourier transform infrared (FT-IR) results showed that the polysaccharide contained β-glucopyranoside bonds. The experimental data of the effects of MFP on probiotics indicated that MFP had prebiotic activity that could effectively promote the proliferation of Bifidobacterium bifidum and Bifidobacterium adolescentis. Furthermore, the in vitro antioxidant activity experiment showed that MFP at the concentration of 10 mg/mL had strong ABTS?+ and ?OH radical scavenging ability and the scavenging rates were 98.93% and 71.28%, respectively.

国家自然科学基金资助项目（21776137）；南京市科技支撑计划项目（201608075）