秦巴山区黑木耳多糖理化性质及体外抗氧化活性

Physicochemical properties and antioxidant activities in vitro of Auricularia auricula polysaccharides in Qinba mountain area

以秦巴山区黑木耳子实体为原料,东北黑木耳为对照,采用热水浸提法、复合酶法和超声法提取黑木耳多糖,对其理化性质及体外抗氧化活性进行分析。通过苯酚-硫酸法、硫酸-咔唑法测定多糖总糖及糖醛酸含量,秦巴山区黑木耳多糖与东北黑木耳多糖相比无显著差异;超声法和酶法制备的黑木耳多糖糖含量、蛋白含量均显著高于热水提取法,糖醛酸含量大小依次为:热水提取>超声提取>酶法提取。气相色谱测定结果表明,秦巴山区黑木耳多糖主要由甘露糖、葡萄糖醛酸、木糖组成,相对摩尔百分比为60.87∶20.83∶9.86,与东北黑木耳多糖相似;与酶法和超声提取相比,热水提取甘露糖、葡萄糖醛酸含量最高,岩藻糖、半乳糖含量最低。通过对过氧化氢清除能力、还原力、金属螯合力检测,发现秦巴山区黑木耳多糖具有良好的抗氧化能力,且其抗氧化能力强弱依次为:超声提取>酶法提取>热水提取。该结果可为秦巴山区特色黑木耳资源的合理开发利用及其多糖的进一步分离纯化、结构解析和生物活性研究提供依据。

Taking Auricularia auricula fruiting body in Qinba mountain area as the research object,the polysaccharides of A.auricula were extracted by hot water,multiple enzyme and ultrasonic extraction method.The physicochemical properties and antioxidant activities of A.auricula polysaccharides in Qinba mountain area were evaluated by the comparation with northeast A.auricula.The results demonstrated that there was no significant difference in sugar and uronic acid contents between A.auricula in Qinba mountain and northeast area determined by phenol-sulfuric acid method and sulfuric acid-carbazole method.The sugar content and protein content of crude polysaccharides of Qinba A.auricula prepared by ultrasonic method and enzyme method were significantly higher than that of hot water extraction,and the content of uronic acid had significantly differences:hot water extraction>ultrasonic extraction>enzymatic extraction.Gas chromatography determination results showed that A.auricula polysaccharides in the Qinba mountain area were mainly composed of mannose,glucuronic acid,xylose,and the relative mole percentage was 60.87∶20.83∶9.86,which was similar to control samples.Compared with enzymatic and ultrasonic extraction,hot water extraction had the highest content of mannose and glucuronic acid,and the lowest content of fucose and galactose.Through the detection of H_(2)O_(2) scavenging ability,reducing power,and metal chelating power,it was found that the A.auricula polysaccharides in the Qinba mountain area had good antioxidant capacities:ultrasonic extraction>enzymatic extraction>hot water extraction.The results could provide a basis for the rational utilization of the characteristic black fungus resources in the Qinba mountains and the further separation and purification,structural analysis,and biological activity researches of A.auricula polysaccharides.