为研究提取溶剂酸碱性和分子量对黑木耳多糖抗氧化活性的影响及其抗氧化相关性，本试验以野生黑木耳为原料制备黑木耳多糖，采用Labscale TFF System超滤系统对黑木耳多糖进行分子量分级，分别测定黑木耳多糖的得率、纯度和抗氧化活性，并使用SPSS软件分析黑木耳多糖分子量与抗氧化活性之间的相关性。结果表明，酸性未脱色黑木耳多糖的得率最高（12.48%），碱性脱色黑木耳多糖的纯度最高（68.78%），中性未脱色黑木耳多糖体外抗氧化活性最好。不同分子量中性未脱色黑木耳多糖抗氧化试验表明，分子量小于30 ku的黑木耳多糖（Sp3）抗氧化活性最好，抗氧化活性与Vc相近。其次是分子量为30 ku~100 ku的黑木耳多糖（Sp2），最差的是分子量大于100 ku的黑木耳多糖（Sp1），Sp3与抗氧化活性之间存在极显著相关（p<0.01），本试验结果为深入开发黑木耳多糖抗氧化产品提供理论依据。

The Auricularia auricula polysaccharides were prepared from wild Auricularia auricula in this study and the molecular weight was fractionated by Labscale TFF System laboratory ultrafiltration system to investigate the effects of acid-base property of extraction solvent and molecular weight on the antioxidant activity of Auricularia auricula polysaccharides The yield, purity and antioxidant activity of the Auricularia auricula polysaccharides were determined and the correlation between molecular weight and antioxidant activity were analyzed by SPSS software. The highest yield of acidic non-decolorized polysaccharides (12.48%) and the highest purity of the alkaline decolorized polysaccharides (68.78%) were obtained, and the neutral decolorized Auricularia auricula polysaccharides had the best antioxidant activity in vitro .The antioxidant experiment of neutral non-decolorized Auricularia auricula polysaccharides with different molecular weights showed that the antioxidant activity of polysaccharides with the molecular weight of less than 30 ku was best, which was similar to that of Vc, followed by the polysaccharides with the molecular weight of 30 ku to 100 ku , and the worst were those with the molecular weight greater than 100 ku .There was a significant correlation between molecular weight and antioxidant activity(p<0.01). The results provided a theoretical basis for the further development of antioxidant products of Auricularia auricula polysaccharide.

中央高校基本科研业务费专项资金资助（2572014CA19、2572014EA02）；黑龙江省自然科学基金面上项目（C2015062）