连钱草多糖的结构表征及抗补体活性研究

Structural characterization and anti-complement activity of polysaccharides from Glechomae Herba

目的分离纯化具有抗补体活性的连钱草均一多糖并表征其结构。方法水提醇沉得连钱草粗多糖,DEAE-52、SephadexG-100柱色谱抗补体活性导向分离得到均一多糖,采用HPGPC、IR、GC、甲基化及核磁等方法对均一多糖进行结构表征,并测定均一多糖的抗补体活性。结果分离所得连钱草均一多糖GLP-1和GLP-2,相对分子质量分别为5370和20040,均主要由阿拉伯糖和半乳糖组成的杂多糖,阿拉伯糖和半乳糖的物质的量比分别为1∶6.3和1∶4.9,GLP-1和GLP-2均具有较强的抗补体活性。结论连钱草均一多糖的结构表征为进一步阐明其抗补体活性的药效物质基础提供了研究基础,同时也为筛选天然补体抑制剂提供了基础。

Objective To isolate and purify the homogeneous polysaccharides from Glechomae Herba through the guidance of anti-complement activity, and study their structures. Methods Crude polysaccharides from Glechomae Herba were extracted by water extraction and alcohol precipitation, then homogeneous polysaccharides were separated by DEAE-52 and Sephadex G-100 column chromatography. The structures of homogeneous polysaccharides were characterized by HPGPC, IR, GC, methylation and NMR, and their anti-complement activities were also determined. Results Two homogeneous polysaccharides GLP-1 and GLP-2 were obtained with the molecular weight of 5 370 and 20 040. They were both heteropolysaccharides composed of arabinose and galactose with the ratio of 1:6.3 and 1:4.9, respectively. Conclusion The structures of GLP-1 and GLP-2 further elucidate the pharmacodynamic basis of their anti-complement activities and provide basis for screening natural complement inhibitors.