黑穗醋栗果实多糖清除自由基活性及结构初步研究

Analysis of Structure and Free Radical Scavenging Activities of Ribes nigrum Polysaccharides

以黑穗醋栗果实为原料,分别用80%、70%、60%、50%、40%、30%乙醇醇沉并采用D4006大孔树脂初步纯化制备6种多糖。分别进行DPPH·、OH·和O2-·清除试验,结果表明6种多糖对自由基均有不同程度的清除作用,其中80%醇沉制备的多糖(BCP-1)对三种自由基的清除作用最强。利用葡聚糖凝胶SephadexG-100对BCP-1纯化制备均一组分BCP-1-Ⅱ,采用气相色谱法和高效液相色谱法对BCP-1-Ⅱ进行单糖组成分析及分子量测定。结果表明:BCP-1-Ⅱ分子量为51880 u,并且由4种单糖组成,摩尔比为阿拉伯糖:甘露糖:葡萄糖:半乳糖=9.08:1.00:15.77:0.41。红外光谱扫描结果表明其含有多糖的特征吸收峰,并且可能含有吡喃糖环及α-糖苷键。

Six kinds of crude polysaccharides were precipitated with 80%, 70%, 60%, 50%, 40% and 30% ethyl alcohol respectively from Ribes nigrum fruit. Then the DPPH？, OH？and O2-？scavenging activities were investigated after purified by macroporous resin D4006. The results showed that six kinds of polysaccharides had certain scavenging activities and the polysaccharides precipitated with 80% ethanol （BCP-1） had stronger free radical elimination capacity. Homogeneous component （BCP-1-Ⅱ） was prepared after further purification from BCP-1 by Sephadex G-100. The compositions of the main fraction BCP-1-Ⅱ were identified and quantified by GC and HPLC. Results indicated that BCP-1-Ⅱhad an average molecular weight of 51880 u and contained arabinose, mannose, glucose and galactose with the molar ratio of 9.08：1.00：15.77：0.41. Characteristic absorption of polysaccharide was shown in IR spectrum and the monomer of backbone of BCP-1-Ⅱ might be α-pyranose.