海藻多糖UH3的结构特征、抗凝和溶栓活性研究

Structural characterization,anticoagulant and thrombolytic activities of the seaweed polysaccharide UH3

目的对海藻多糖UH3的结构特征、抗凝血和溶栓活性进行研究。方法通过热水提取法,从海藻中提取硫酸多糖,采用强阴离子交换色谱和凝胶渗透色谱对多糖进行分离纯化;采用高效液相色谱、高效凝胶渗透色谱(HPGPC)、红外光谱及甲基化方法对多糖的结构进行表征;通过活化部分凝血活酶时间(APTT)、凝血酶时间(TT)、凝血酶原时间(PT)及血凝块溶解法研究多糖体外抗凝血和溶栓活性。结果多糖UH3在HPGPC色谱图上呈单一对称峰,分子量为50.3kDa,硫酸根和糖醛酸含量分别为12.27%和12.85%;UH3主要由鼠李糖组成,含有少量葡萄糖醛酸和木糖;UH3糖链中鼠李糖主要以→4)-Rhap-(1→、→3,4)-Rhap-(1→及少量的T-Rhap形式存在,木糖以→4)-Xyl p-(1→和T-Xyl p形式存在,糖醛酸以→4)-GlcAp-(1→和T-GlcAp形式存在;硫酸根主要位于→4)-Rhap-(1→的C-3位。多糖UH3对APTT和TT有显著延长作用,并能明显提高溶栓率。结论海藻多糖UH3是1种结构新颖的具有抗凝和溶栓活性的硫酸多糖。

Objective To investigate the structural characterization,anticoagulant and thrombolytic activity of the seaweed polysaccharide UH3.Methods The crude polysaccharide was extracted from green alga by hot water,and further purified by strong anion exchange chromatography and gel permeation chromatography.The structure of the polysaccharide was characterized by high performance liquid chromatography,high performance gel permeation chromatography(HPGPC),Fourier infrared spectroscopy(FT-IR)and methylation analysis.The anticoagulant and thrombolytic activities of the polysaccharide were determined by activated partial thromboplastin time(APTT),thrombin time(TT),prothrombin time(PT),and clot lytic assay in vitro.Results The polysaccharide of UH3 appeared as a single peak in the HPGPC chromatogram,and its average molecular weight was about 50.3 kDa.The contents of sulfate esters and uronic acid were 12.27% and 12.85%,respectively.The polysaccharide UH3 was mainly composed of rhamnose with small amounts of glucuronic acid and xylose.The rhamnose in polysaccharide UH3 was existed in the forms of→4)-Rhap-(1→,→3,4)-Rhap-(1→and small amount of T-Rhap,the xylose was existed as→4)-Xyl p-(1→and T-Xyl p,and the glucuronic acid was existed as→4)-GlcAp-(1→and T-GlcAp.The sulfate ester was substituted at the C-3 of→4)-Rhap-(1→ residues.Polysaccharide UH3 could significantly prolong APTT and TT,and significantly increase clot lytic rate in vitro.Conclusion The seaweed polysaccharide UH3 was a novel sulfated polysaccharide with anticoagulant and thrombolytic activities.