决明子多糖定量分析方法研究

摘要

The monosaccharide composition of monosaccharide composition of semen cassia polysaccharides has been studied. The effects of the glucose standard and the mixed standards according to the molar proportion of monosaccharide units in semen cassiae polysaccharides have been evaluated. The purification of crude polysaccharide extracts by use of PVPP/alcohol precipitation was to remove polyphenols and proteins from polysaccharides. The reliability of the methodology was verified. The results showed that the monosaccharide molar proportion of semen cassiae polysaccharides as the following∶mannose∶glucuronic acid∶aminogalactose∶glucose∶galactose∶xylose∶arabinose=43.3∶4.3∶1.2∶6.4∶21.3∶18.8∶4.8. The polysaccharide content calibrated by the mixture standard curve was more accurate(relative error:-0.14%)than the one using the glucose standard curve(relative error:37.75%). The treatment of PVPP or/and alcohol precipitation removed polyphenols and proteins effectively from crude polysaccharide extracts. The analytic method was confirmed with a good reproducibility,high precision,good stability and higher recovery rate(RSD<3%). This methodology could be used to determine semen cassia polysaccharides in a rapid and accurate manner.%该文以决明子为原料，对决明子多糖的单糖组成进行了研究，同时比较了单一标品和混合标品对多糖测定结果的影响；考察了PVPP/醇沉处理对决明子粗多糖提取物中多酚、蛋白和多糖的影响，并从方法学上验证该方法。结果表明，决明子多糖组成中，单糖摩尔比为甘露糖∶葡萄糖醛酸∶氨基半乳糖∶葡萄糖∶半乳糖∶木糖∶阿拉伯糖=43.3∶4.3∶1.2∶6.4∶21.3∶18.8∶4.8。混标标准曲线和葡萄糖标准曲线所校正获得的多糖含量与真实值的相对误差分别为-0.14%和37.75%，即混标标准曲线比葡萄糖标准曲线更适用于校正决明子多糖含量。同时，PVPP处理和醇沉处理对决明子多糖提取液中干扰物质（多酚和蛋白质）分别有吸附和沉降作用。本决明子多糖定量分析方法具有重现性好、精密度高、稳定性好和回收率高等特点（RSD＜3%）。该方法可对决明子多糖进行更为准确、快捷的定量检测。