基于特征脂肪酸的中药海藻鉴别研究

Chemical Identification of TCM Sargassum Based on Characteristic Fatty Acids

目的利用植物脂质组学和化学分类学开展羊栖菜与其同属易混马尾藻的鉴别研究。方法收集27批羊栖菜,靶向建立了脂肪酸气相色谱-质谱(GC-MS)指纹图谱;运用主成分分析、正交偏最小二乘判别分析等化学模式识别方法,比较了羊栖菜与同属其他8种22批马尾藻,建立了海藻饮片判别模型;基于羊栖菜与其他马尾藻的差异脂肪酸,结合脂肪酸生合成途径分析,筛选质量标志物。结果指纹图谱共标定29个共有脂肪酸,相似度均大于0.96。化学模式识别法能够很好区分羊栖菜与同属其他8种22批马尾藻,以此建立的判别模型能够准确验证15批市售海藻饮片。结合差异脂肪酸与脂肪酸生合成途径分析,发现单不饱和脂肪酸在化学分类中的重要作用,提出比值C20∶1 n-9/C16∶1 n-7可作为羊栖菜鉴别的候选质量标志物,14批市售海藻饮片可被准确验证。结论本研究建立了羊栖菜与同属易混马尾藻的判别模型,发现了脂肪酸质量标志物,为中药海藻真伪鉴别方法的制定提供参考。

OBJECTIVE To study the identification of Sargassum fusiforme and other sargassos(algae from the genus Sargassum)by targeted lipidomics combined with chemotaxonomy methods.METHODS Twenty-seven batches of S.fusiforme were collected and the GC-MS fingerprint of fatty acids(FAs)was established.The principal component analysis and orthogonal partial least squares discriminant analysis were used to compare S.fusiforme with other 8 species,total 22 batches of sargassos.Based on the differential FAs between S.fusiforme and other sargassos,combined with the analysis of FA biosynthesis pathway,the Q-marker was screened.RESULTS A total of 29 common FAs were identified by the fingerprint,and the similarity was greater than 0.96.The chemical pattern recognition method can well distinguish S.fusiforme from other 8 species,and the discrimination model established by this method can accurately verify 15 batches of commercial slices.Based on the analysis of differential FAs and FA biosynthesis pathway,monounsaturated fatty acid was found to play an important role in chemical classification.The ratio C20∶1 n-9/C16∶1 n-7 was proposed to be used as a candidate Q-marker for the identification of S.fusiforme and 14 batches of commercial slices can be accurately verified.CONCLUSION This study establishes the identification model of S.fusiforme and other confused sargassos,finds the Q-marker of FAs,and provides a reference for the establishment of the identification method of TCM SARGASSUM.