中文摘要：

目的从防风Saposhnikovia divaricata中提取多糖并对其进行理化性质及结构特征的分析。方法采用DEAE-52纤维素和Sephadex G-200凝胶柱色谱分离纯化，获得防风多糖主要成分SPS0和SPS1，通过紫外光谱（uv）、热稳定性实验、红外光谱（IR）、刚果红实验、环境扫描电镜（ESEM）、原子力显微镜（AFM）对防风多糖进行理化性质、形貌特征及结构特征分析。结果SPSO和SPS1糖醛酸的质量分数分别为12．07％、0．95％；IR光谱显示SPSO含有-COOH的特定吸收峰；刚果红实验表明SPS0具有三股螺旋结构，SPS1没有三股螺旋结构；ESEM、AFM观察显示SPS0形貌工整，为链状多分枝结构，SPS1多糖形貌不规则，有少量分枝结构。结论SPS0是一种具多分枝结构的酸性多糖；SPS1是一种含β-D-吡喃环的均一多糖，热稳定性较高。

英文摘要：

Objective To extract Saposhnikovia divaricata polysaccharides （SPS） and to analyze the characteristics of their physicochemistry and structures. Methods Two main polysaccharides, SPS0 and SPS 1, were obtained by DEAE-52 and Sephadex G-200 column chromatography; UV spectrophotometer, heat stability test, IR spectrometry, Congo-red test, environmental scanning electron microscope （ESEM）, and atomic force microscope （AFM） were used to determine the physicochemical, morphological, and structural properties ofpolysaccharides. Results The uronic acid contents of SPS0 and SPS1 were 12.07% and 0.95%, respectively. IR spectrometry showed SPS0 had a specific absorption peak of-COOH. Congo-red test indicated that only SPS0 had a triple helix conformation. ESEM and AFM showed that SPS0 was neat and orderly, with a hyper branched structure, but irregular figure and fewer branches were observed in SPS1. Conclusion SPS0 is an acidic and hyper branched polysaccharide, while SPS1 is a homogeneous polysaccharide including β-D-pyranose sugar residues with better heat stability.