Integrated metabolomic and transcriptomic analysis reveals variation in the metabolites of Dendrobium officinale, Dendrobium huoshanense, Dendrobium nobile.

INTRODUCTION: Dendrobium is a perennial herb of the genus Dendrobium in the orchid family. Generally, Dendrobium officinale (TP) and Dendrobium huoshanense (HS) are both considered to have the function of yin-nourishing, while Dendrobium nobile (JC) has better efficacy of heat-clearing. However, because of the wide variety of Dendrobium species, the classification and clinical application of Dendrobium are often confused clearly distinguished in different medicinal uses. OBJECTIVE: In order to compare the differentially accumulated metabolites (DAMs) and differentially expressed genes (DEGs) of the three Dendrobium. METHODS: We selected TP, HS, and JC cultivated on stone for metabolomic and transcriptomic analyses between 2 and 3 years. RESULTS: The results showed that a total of 489 metabolites were obtained, including 72 were DAMs. The 72 DAMs were mainly enriched in metabolic pathways and biosynthesis of secondary metabolites. Transcriptome analysis results showed that 1,038 annotated DEGs were identified among the three Dendrobium species. The comprehensive analysis showed that the three Dendrobium differed in the distribution of the content of four major active components: flavonoids, amino acids, alkaloids, and sugars and alcohols, among which the DAMs and DEGs were mainly enriched in metabolic pathways and secondary metabolite biosynthesis. CONCLUSION: In this study, metabolomics and transcriptomics were utilized to compare the differences among the three species of Dendrobium, to provide theoretical references for future research and selection of different species of Dendrobium based on different medicinal uses, and to lay the foundation for further research on the biosynthesis of flavonoids in Dendrobium.

Does the Metabolome of Wild-like Dendrobium officinale of Different Origins Have Regional Differences?

Dendrobium officinale, as a traditional Chinese medicine, has considerable commercial value and pharmacological activity. Environmental factors of different origins have a great influence on Dendrobium officinale metabolites, which affect its pharmacological activity. This study sought to identify the differential metabolites of wild-imitating cultivated D. officinale stems of different origins. Using the widely-targeted metabolomics approach, 442 metabolites were detected and characterized, including flavonoids, lipids, amino acids and derivatives, and alkaloids. We found that although the chemical constitution of D. officinale cultured in the three habitats was parallel, the contents were significantly different. Meanwhile, the KEGG pathway enrichment analysis revealed that the distinctive metabolites among the three groups were mainly involved in flavone and flavonol biosynthesis. To further explore the different contents of flavonoids, HPLC was performed on four main flavonoid contents, which can be used as one of the references to distinguish D. officinale from different growing origins. In conclusion, a comprehensive profile of the metabolic differences of D. officinale grown in different origins was provided, which contributed a scientific basis for further research on the quality evaluation of D. officinale.