竹叶多糖分离纯化及抗氧化能力的研究

对超临界CO2流体萃取技术提取的竹叶粗多糖采用分级醇沉、脱蛋白质及纤维素柱层析等技术分离纯化,研究分离纯化后的竹叶多糖产物的物化指标。研究结果表明:经超临界CO2流体萃取技术提取得到的毛竹叶粗多糖,采用体积分数为70%的乙醇沉淀,得到预纯化产物,预纯化产物得率17.75%,多糖含量9.586 mgg,总抗氧化能力2.556 mgg VC;预纯化产物再经Sevag法脱蛋白质及DEAE-52纤维素层析柱层析,获得一种中性竹叶多糖,其平均分子量为5.051×104,IC50值为0.178 mgg竹叶多糖,与VC(IC50值为0.158 mgg)相比,具有较好的DPPH清除能力。 

Isolation,purification technique and antioxidant capacities of polysaccharides from bamboo leaves

We extracted crude polysaccharide (BPS) from bamboo leaves by the method of supercritical CO2 extraction. The BPS was fractionated and precipitated by ethanol, and then protein was removed and further separated and purified by cellulose column. Physical and chemical indicators of the purified BPS were investigated. Results showed that: the crude polysaccharide extracted with supercritical CO2 technique was precipitated by ethanol at the volume concentration of 70%, obtaining a yield of pre-purified product 17.75%, the content of polysaccharide in it was 9.586 mg蛐g, and its total antioxidant capacity was 2.556 mg蛐g VC . Protein in the pre-purified product was removed by Sevag. Then neutral polysaccharide was obtained through DEAE-52 cellulose column, with an average molecular weight of 5.051í104 . Its IC50 value was 0.178 mg蛐g BPS, showing a better DPPH scavenging ability than VC ( IC50 value 0.158 mg蛐g) .