Characterization of metabolite landscape distinguishes wild from cultivated Polygonati Rhizomes by UHPLC-Q-TOF-MS untargeted metabolomics

Rhizome, a modified subterranean plant stem, has been used in China for centuries as a Traditional Chinese Medicine (TCM). Polygonati Rhizome (PR) is a well-known species in the Rhizome family. Previous studies show that PR might be beneficial in the treatment of osteoporosis, cancer, diabetes, and many other diseases because of its properties such as antioxidant property. Thus cultivated PR strains were developed to fulfil the increasing demands. However, the metabolite profile differences between wild-type and cultivated PR remain largely unknown. Here, we performed unbiased and untargeted quantitative mass spectrometry-based metabolomics on 1 wild strain and 3 cultivated strains. A total of 1126 metabolites were identified on all 4 strains. Analyses of these data with unsupervised and supervised approaches identified common metabolites in all 4 strains as well as strain-specific metabolites. Next, we conducted a metabolomic-wide pairwise correlation analysis on metabolite abundance and discovered 577 significantly correlated metabolite-metabolite pairs by Pearson's correlation test. Importantly, KEGG enrichment analysis indicated that phenylpropanoids biosynthesis was the most differentially expressed pathway between cultivated and wild-type PR. By contrast, common metabolites on all 4 strains might suggest shared therapeutic targets. In summary, the systematic, untargeted metabolomics profiling of 4 PR strains and comprehensive data analyses provide invaluable resources to the understanding of the metabolite landscape and shed light on potential therapeutic applications for the treatment of diseases.