Polysaccharides from numerous traditional Chinese medicines have been proven as the bioactive ingredients and are hence used as the quality control markers. However, the assessment criteria always show a poor specificity, due to the lack of matic comparison among the analogous herbs. In the present study, two similar materials, namely sea-tangle and sargassum, were selected as the model herbs to develop more specific methods for quality control. Two well-established methods, determination of the total polysaccharides content and monosaccharides composition analysis, were both employed. Based upon the quantitative results, the evaluation criteria of the polysaccharides contents of not less than 2.0% and 1.7% were proposed for sea-tangle and sargassum, tively. Nine identical monosaccharide derivatives appeared on the HPLC chromatograms of the hydrolysis and derivatized solutions of the two drugs. Principal component analysis and orthogonal partial least squares discriminant analysis using the peak areas of monosaccharides derivatives as the variables were performed, and the results indicated that mannuronic acid and xylose with the opposite concentrations in the two drugs were the differential components. A discriminative criterion using the peak area ratio of these two monosaccharides derivatives was proposed for the qualitative identification. In conclusion, a more specific and quantitative quality control method was developed for sea-tangle and sargassum.
LONG Hua-LiZHANG Jing-XianGUO Ji-LingSUI Guo-QiHOU Jin-JunYANG Wen-ZhiHAN Su-MeiWU Wan-YingGUO De-An
目的:测定不同品种沙蚕中15种氨基酸含量并进行多元统计分析。方法:采用酸水解法制备水解氨基酸样品溶液,以异硫氰酸苯酯为衍生化试剂衍生后进行HPLC分析。采用CAPCELL PAK C18色谱柱(4.6 mm×250 mm,5μm),以0.1 mol·L^(-1)醋酸钠溶液(p H 6.5)-乙腈(93∶7)为流动相A,乙腈-水(8∶2)为流动相B,梯度洗脱,流速1.0 m L·min^(-1),柱温40℃,检测波长254 nm,进样量2μL。采用主成分分析法对不同品种沙蚕中15种氨基酸相对含量进行分析。结果:15种氨基酸在一定浓度范围内呈良好线性关系,线性相关系数r值均大于0.999 6,加样回收率(n=6)为96.1%~101.5%,氨基酸衍生溶液在12 h内稳定;氨基酸相对含量的主成分分析可以达到降维的目的,各品种沙蚕样品得到较好的区分。结论:所建立的条件方法可靠,精密度和重复性良好,可用于沙蚕中水解氨基酸含量的测定,主成分分析可用于揭示沙蚕的特征氨基酸,为沙蚕品质特征评价提供依据。
