阿克苏野生牛肝菌多糖提取优化及不同组分抗氧化活性分析

Extraction and antioxidant activity of different polysaccharide components from the wild boletus in Aksu region

【目的】研究阿克苏野生牛肝菌多糖的最佳提取工艺,分析不同多糖组分的理化性质和抗氧化能力,为野生牛肝菌多糖的深入开发及利用提供科学参考。【方法】以阿克苏地区野生牛肝菌为材料,优化多糖水提条件,采用体积分数为40%和80%的乙醇进行分级沉淀,得到2种粗多糖组分LD-40和LD-80;测定多糖的水溶性、持水力和粘度,清除DPPH自由基、羟基自由基进行还原力试验,评价2种多糖组分的特性。【结果】牛肝菌多糖的最佳提取工艺条件为料液比1:30,温度80℃,时间3 h,多糖最高得率为13.36%。乙醇分级沉淀获得LD-40和LD-80分别占总多糖的92.37%和7.63%,各自水溶性分别为66.9%和74.9%,持水力为7.71和6.16 g/g。相同浓度下,LD-40粘度较LD-80更强,但LD-80抗氧化能力比LD-40强。【结论】阿克苏地区野生牛肝菌富含多糖,具有较好的持水力,但抗氧化活性较弱。

【Objective】To optimize the extraction conditions of polysaccharides from the wild boletus in Aksu region and determine the physical properties and antioxidant capacity of different polysaccharide components.【Methods】The wild boletus was sampled from Aksu region,and water extraction conditions of polysaccharide were optimized.Two polysaccharide components,LD-40 and LD-80,were obtain by fractional precipitation of ethanol with volume fraction of 40%and 80%.The polysaccharide properties of water solubility,water retention and viscosity were tested.The antioxidant capacity was evaluated by free radical scavenging of DPPH and hydroxyl and reducing power experiments.【Results】The optimal extraction conditions were solid-liquid ratio 1∶30,temperature at 80℃,time for 3 h,then the yield of polysaccharide was 13.36%.Polysaccharide components,LD-40 and LD-80,obtained from ethanol fractional precipitation accounted for 92.37%and 7.63%of the total polysaccharide,respectively.The water solubility of LD-40 and LD-80 was 66.9%and 74.9%,respectively,and the water holding capacities were 7.71 and 6.16 g/g,respectively.At the same concentration,the viscosity of LD-40 was stronger than that of LD-80,but LD-80 had stronger antioxidant capacity than LD-40.【Conclusion】The wild boletus in Aksu region is rich in polysaccharides which has good water holding capacity,but the antioxidant activity is weak.The results can provide scientific reference for the further development and utilization of wild boletus polysaccharides.