State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University , 38 Xueyuan Road, Beijing 100191, China.
South China Botanical Garden, Chinese Academy of Sciences , 723 Xingke Road, Guangzhou, Guangdong 510650, China.
Anal Chem. 2017 Mar 7;89(5):3146-3153. doi: 10.1021/acs.analchem.6b04919. Epub 2017 Feb 23.
Secondary metabolites are usually the bioactive components of medicinal plants. The difference in the secondary metabolisms of closely related plant species and their hybrids has rarely been addressed. In this study, we conducted a holistic secondary metabolomics analysis of three medicinal Glycyrrhiza species (G. uralensis, G. glabra, and G. inflata), which are used as the popular herbal medicine licorice. The Glycyrrhiza species (genotype) for 95 batches of samples were identified by DNA barcodes of the internal transcribed spacer and trnV-ndhC regions, and the chemotypes were revealed by LC/UV- or LC/MS/MS-based quantitative analysis of 151 bioactive secondary metabolites, including 17 flavonoid glycosides, 24 saponins, and 110 free phenolic compounds. These compounds represented key products in the biosynthetic pathways of licorice. For the 76 homozygous samples, the three Glycyrrhiza species showed significant biosynthetic preferences, especially in coumarins, chalcones, isoflavanes, and flavonols. In total, 27 species-specific chemical markers were discovered. The 19 hybrid samples indicated that hybridization could remarkably alter the chemical composition and that the male parent contributed more to the offspring than the female parent did. This is hitherto the largest-scale targeted secondary metabolomics study of medicinal plants and the first report on uniparental inheritance in plant secondary metabolism. The results are valuable for biosynthesis, inheritance, and quality control studies of licorice and other medicinal plants.
次生代谢物通常是药用植物的生物活性成分。然而，亲缘关系密切的植物物种及其杂种之间次生代谢的差异很少被关注。在这项研究中，我们对三种作为常用草药甘草的药用甘草属植物（乌拉尔甘草、光果甘草和胀果甘草）进行了全面的次生代谢组学分析。通过内转录间隔区和 trnV-ndhC 区的 DNA 条形码鉴定了 95 批样品的甘草属（基因型），并通过基于 LC/UV 或 LC/MS/MS 的 151 种生物活性次生代谢物的定量分析揭示了它们的化学型，包括 17 种黄酮糖苷、24 种皂苷和 110 种游离酚类化合物。这些化合物代表了甘草生物合成途径中的关键产物。对于 76 个纯合子样品，三种甘草属植物表现出明显的生物合成偏好，特别是在香豆素、查尔酮、异黄酮和黄酮醇方面。总共发现了 27 种种特异性化学标志物。19 个杂交样品表明，杂交可以显著改变化学成分，并且父本比母本对后代的贡献更大。这是迄今为止对药用植物进行的最大规模的靶向次生代谢组学研究，也是首次报道植物次生代谢中的单亲遗传。研究结果对于甘草和其他药用植物的生物合成、遗传和质量控制研究具有重要价值。
