柳叶白前粗多糖组成、形貌特征及抗氧化研究

Study on Composition, Morphological Characteristics and Antioxidant Activity of Crude Polysaccharide from Cynanchum Stauntonii

目的提取获得柳叶白前粗多糖(CSP90),对其单糖组成、形貌特征和抗氧化活性进行分析。方法通过水提醇沉法提取CSP90,利用HPLC测定单糖组成,通过扫描电子显微镜分析形貌特征,并测定CSP90对1,1-二苯基-2-三硝基苯肼(DPPH)自由基的清除作用。结果CSP90的糖含量和蛋白质含量分别为94.7%和2.86%,主要由葡萄糖、半乳糖和阿拉伯糖组成,其微观结构的聚集状态部分呈凹凸不平的不规则薄碎片状结构,边缘不平整,而部分结构呈光滑连绵的薄片,伴有一些分支,说明CSP90呈无定形结构。在1.6 mg·mL^(-1)的浓度下,CSP90与抗坏血酸(VC)对DPPH自由基的清除率分别为96.5%和97.6%,表明CSP90具有较好的DPPH自由基清除活性。结论CSP90含有多种单糖,并且对DPPH自由基的清除能力较好,有望被开发成一种天然的抗氧化剂。

Objective The crude polysaccharides were extracted and purified from Cynanchum stauntonii(CSP90),and the monosaccharide composition,morphological characteristics and antioxidant activities were analyzed.Methods CSP90 was obtained by water extraction and alcohol precipitation.The monosaccharides composition of CSP90 was determined by highperformance liquid chromatography(HPLC).The morphological characteristics were analyzed by scanning electron microscopy.While the 1,1-diphenyl-2-trinitrophenylhydrazine(DPPH)radical scavenging activity of CSP90 was further determined.Results The sugar and protein contents of CSP90 were 94.7%and 2.86%,respectively.CSP90 was mainly composed of glucose,galactose,and arabinose.Some of the microstructures of CSP90 were irregular and thin fragments with uneven edges,while some of the microstructures were smooth and continuous slices with some branches,indicating that CSP90 had an amorphous structure.At a concentration of 1.6 mg·mL^(-1),the scavenging rates of DPPH radical by CSP90 and ascorbic acid(VC)were 96.5%and 97.6%,indicating that CSP90 had better DPPH radical scavenging activity.Conclusion CSP90 contained a variety of monosaccharides and had a good DPPH radical scavenging ability.It is hoped that CSP90 will be developed into a natural antioxidant.