Comparative Analysis of Components and Biological Activities in Different Parts of Gastrodia elata Blume

Background:Gastrodia elata Blume (GE) is a widely used plant with both medicinal and edible properties. Besides the underground tubers, its above-ground parts also have certain medicinal potential. However, most of these resources are frequently discarded during production and processing. The differences in chemical composition and bioactivity among different parts of GE remain unclear. Methods: In this research, the non-targeted metabolomics method was used to detect the metabolites in the stem (ST), capsule shell (CS), seed (SE), arrow end (AE), middle end (ME), and navel end (NE) of GE. Differential metabolites were screened by multivariate statistical analysis. The pathway enrichment analysis of differential metabolites was carried out by the Kyoto Encyclopedia of Genes and Genomes (KEGG) platform. The antioxidant and α-glucosidase inhibitory activities of extracts from six different parts of GE were determined in vitro, followed by correlation analysis between biological activities and key metabolites. Results: Metabolites in different parts of GE were significantly different, including lipids, organic acids, organoheterocyclic compounds, phenylpropanoids, benzenoids, and organic oxygen compounds. The characteristics of metabolites in the underground and above-ground parts of GE were clearly distinct. The contents of lipids, organoheterocyclic compounds, and organic acids were the highest in SE, SE and CS, ST, and AE, respectively. The KEGG pathway enrichment analysis preliminarily suggested that the differences in metabolites from different parts of GE might be related to the arginine biosynthesis pathway, which involves seven metabolites, including L-glutamic acid, L-arginine, L-ornithine, and L-aspartate. Compared with the tuber (the conventional medicinal part), ST and CS exhibited excellent antioxidant properties and inhibitory activity against α-glucosidase. Correlation analysis indicated that L-arginine and L-aspartate were positively correlated with the biological activity of GE and may be components preliminarily associated with its difference in activity. Conclusions: This study provided preliminary comparative evidence for the metabolite characteristics from different parts of GE, thereby facilitating the further development and utilization of its above-ground resources.