南瓜多糖的性质及光谱分析

Properties and Analysis of Pumpkin Polysaccharide by UV and Infrared Spectrometries

采用热水浸提和乙醇沉淀的方法提取南瓜多糖,Sevage法除蛋白,活性炭脱色,对南瓜多糖的理化性质、提取率、含量、组成和结构进行了研究,南瓜多糖呈灰白色粉末,溶于水,不溶于有机溶剂。碘-碘化钾反应呈阴性,说明提取物为非淀粉性多糖。提取率5.34%,总糖含量为97.93%,紫外光谱扫描结果表明南瓜多糖几乎不含核酸和蛋白质;红外吸收光谱检测表明,在3433、2949、1749、1612、1416、1333、1238、1147、1101、1018、833、763、637、536、427cm-1处表现为典型的多糖特征吸收峰;南瓜多糖是一种酸性多糖,同时存在呋喃环和吡喃环,该多糖是以α型糖苷键相连结的杂多糖。

Pumpkin polysaccharide was extracted with hot--water,precipitated with ethanol and decolourized by active carbon. The protein in crude polysaccharide was removed by Sevage method. The physical and chemical characters, extraction rate, contents, compositions of pumpkin polysaccharide were studied. Pumpkin polysaccharide was pearl powder, water-soluble, insoluble in organic solvents. The negative reaction with potassium iodide show that pumpkin polysaccharide was non-starch polysaccharide. Extraction rate was 5. 34% and the content of polysaccharide was 97. 93%. UV spectrum showed that there was little DNA and protein. Typical absorption peaks of infrared spectroscopy at 3 433,2 949,1 749,1612,1416,1 333,1 238,1 147,1 101,1 018,833,763, 637,536,427cm^-1 indicated pumpkin polysaccharide is linked to the heteropolysaccharide by aglycosidic bond,and is acid polysaccharide and comprises furan and pyran parts.