桑叶多糖的分离纯化及其抗凝血活性的研究

Isolation,purification and anticoagulant activity of the polysaccharide from the leaves of mulberry

为了研究桑叶多糖不同组分在体外的抗凝血活性,采用水提醇沉法提取桑叶粗多糖,聚酰胺进行脱色和脱蛋白.用DEAE sepharose CL-6B和sepharose CL-6B对桑叶多糖进行纯化,得到5种水溶性多糖组分(MPS-1、MPS-2a、MPS-2b、MPS-2c和MPS-3).单糖检测结果表明:桑叶多糖主要是由半乳糖、葡萄糖、鼠李糖、阿拉伯糖、木糖和甘露糖等组成.体外抗凝血活性检测显示5种桑叶多糖组分均能延长活化部分凝血活酶时间(activated partial thromboplastin time,APTT)和凝血酶时间(thrombin time,TT)、而对凝血酶原时间(prothrombin time,PT)影响不显著,说明它们是通过影响内源性途径或共同途径而发挥抗凝血作用;与对照相比,MPS-2b在试验浓度范围内对APTT和TT的效果达到极显著,表明MPS-2b有潜力开发成抗凝血活性物质.

To study different components of mulberry polysaccharides and their anticoagulant activity,the crude mulberry polysaccharides were extracted by water and precipitated by alcohol.The crude polysac- charides xcre decolorized and deproteinized by polyamide. Five water-soluble polysaccharides （MPS-1, MPS-2a, MPS-2b, MPS-2c and MPS-3） were purified by DEAE sepharose CL-6B chromatograph column and sepharose CL-6B chromatograph column. The monosaccharide compostion of MPS was composed mainly of galaetose, glucose, rhamnose, arabinose, xylose and mannose and so on. APTT, PT and TT in vitro tests showed that they prolonged APTT and TT,but had no significant effect on PT. The result confirmed these in the regulation of coagulation initiated via the intrinsic pathway or common pathwayl MPS-2b significantly prolonged APTT and TT compared to saline in experiment concentrations.These results suggest that the mulberry polysaccharide MPS-2b can be explored as a kind of natural potential anticoagulant.