桑枝皮多糖的提取及组成成分与体外生物活性分析

Extraction,Composition and in vitro Bioactivity of Polysaccharide from Mulberry Branch Bark

为了更好地发掘桑枝皮的药用价值,采用热水浸提法从桑枝皮中分离提取多糖,其得率达到28.5%。采用薄层层析(TLC)法和非衍生化高效液相色谱(HPLC)法分析桑枝皮多糖的组成成分,初步推定桑枝皮多糖为一种杂多糖,由鼠李糖、木糖、阿拉伯糖、甘露糖、葡萄糖和半乳糖等单糖组成。桑枝皮多糖的体外生物活性试验显示其具有较强的对DPPH自由基的清除能力(IC50为1.7mg/mL)和对α-葡萄糖苷酶的抑制活性(IC50为0.298mg/mL)。上述结果提示桑枝皮多糖是降血糖和抗氧化的天然药物资源。

In order to facilitate exploitation of mulberry branch bark＇s medicinal value,hot water method was used to extract polysaccharide from mulberry branch bark and the extraction rate reached 28.5%.Composition of the polysaccharide was analyzed with thin-layer chromatography （TLC） and non-derivatization high performance liquid chromatography （HPLC）.It was preliminarily inferred that the polysaccharide from mulberry branch bark was a mixed polysaccharide which contained rhamnose,xylose,arabinose,mannose,glucose and galactose etc.In vitro bioactivity assay indicated that mulberry branch bark polysaccharide had high scavenging ability to DPPH free radical （IC50=1.7 mg/mL） and strong inhibition activity to α-glucosidase （IC50=0.298 mg/mL）.The above results suggest that mulberry branch bark polysaccharide is a natural medicinal resource with antidiabetes and antioxidant activities.