商陆根部多糖的分离、纯化及其体外抗氧化活性

本研究从商陆根部提取分离出商陆多糖,并对该多糖含量进行测定及体外抗氧化活性研究。商陆根部经石油醚回流脱脂、热水抽提、脱色、乙醇沉淀等处理可从中提取出粗多糖。多糖经三氯乙酸脱蛋白纯化,再分别以考马斯亮蓝法和蒽酮-硫酸法测定其蛋白质含量和糖含量,并通过采用清除羟自由基和超氧自由基能力测定法、β-胡萝卜素-亚油酸法,以抗坏血酸（Vc）为对照,来分析粗多糖和纯多糖的体外抗氧化能力。采用水提法提取的粗多糖,含有10.69%的蛋白质和60.91%的多糖;纯化后的多糖糖含量达到91.04%。商陆粗多糖、纯多糖及Vc对羟自由基（·OH）清除率的IC50分别是1.26mg/mL、4.78mg/mL和0.224mg/mL;对超氧自由基（O2-·）清除率的IC50分别为1.91mg/mL、2.28mg/mL和0.123mg/mL;对β-胡萝卜素-亚油酸体系的抑制作用的IC50分别为0.471mg/mL、0.692mg/mL和0.379mg/mL。实验结果表明商陆多糖是一种较好的抗氧化剂,可作为潜在天然抗氧化剂应用于食品和医药工业中。

Isolation and Purification of Polysaccharides from the Root of Phytolacca acinosa Roxb and their in vitro Antioxidant Activity

In this research,we have extracted and determined the content of the polysaccharides from the root of Phytolacca acinosa Roxb,and we also investigated the in vitro antioxidant activity of the obtained polysaccharides.The polysaccharides from the root of Phytolacca acinosa Roxb were prepared by degreasing with petroleum ether,extraction with hot water,decolourization,precipitation with ethanol as well as removing protein withtrichloroacetic acid（TDA）.In crude polysaccharide,the content of protein and polysaccharide were assessed with coomassie brilliant blue method and anthrone-sulfuric acid method,respectively.Taking ascorbic acid（Vc） as compared sample,the antioxidant activity of polysaccharides from the root of Phytolacca acinosa Roxb has been evaluated by scavenging hydroxyl free radical（·OH）,superoxide anion（O2-·） and β-carotene-linoleic Acid methods.Analytical experiments showed that crude polysaccharide from the root of Phytolacca acinosa Roxb contained 60.84 % polysaccharide and 10.82% protein,while the purified sample contained 92.01% polysaccharide.The IC50 for crude polysaccharide,purified polysaccharide and Vc was1.26 mg/mL,4.78 mg/mL,0.224 mg/mL,respectively,in scavenging·OH,while 1.91 mg/mL,2.28 mg/mL and 0.123 mg/mL in scavenging O2-·,0.471 mg/mL,0.692 mg/mL and 0.379 mg/mL in inhibiting β-carotene-linoleic acid system.The experimental results indicated that as a satisfactory antioxidant,polysaccharides from the root of Phytolacca acinosa Roxb might be applied as natural antioxidant in food and pharmaceutical industries.