低温提取南瓜多糖的理化性质及清除DPPH自由基作用

The Physicochemical Properties and Radical Scavenging Activity of Pumpkin Polysaccharides Extracted at Low Temperature

首次采用低温水提的方法对南瓜多糖进行提取,从得率、理化性质、清除DPPH自由基活性方面对低温提取的南瓜多糖进行了研究,并与高温提取的南瓜多糖进行了比较。实验结果表明:经缓冻处理后,室温提取的南瓜多糖得率为5.06%,低于70℃提取的多糖得率5.48%(P>0.05)。低温提取的南瓜多糖为白色粉末I,2-KI反应阴性,分子量分布主要为4 ku^270 ku;低温南瓜多糖清除DPPH自由基的效果明显高于高温提取的南瓜多糖(P<0.05)。

Crude water-soluble pumpkin polysaccharides were extracted from pumpkin pulp at room temperature（25 ℃）.The yield,physicochemical properties and DPPH radical scavenging activity of polysaccharides were studied and compared with which obtained at 70 ℃.The results indicated that after slow freezing treatment,the yield of polysaccharides extracted at 25 ℃ was 5.06 % and that extracted at 70 ℃ was 5.48 %.Their difference was not obviously.The pumpkin polysaccharides obtained at 25 ℃ were white in colour,non-strach,and molecular weight ranged from 4 ku to 270 ku.Moreover the DPPH radical scavenging activity was higher than the polysaccharide obtained at 70 ℃.