Wild imitating vs greenhouse cultivated Dendrobium huoshanense: Chemical quality differences.

Dendrobium huoshanense (D. huoshanense) has been used as functional food supplements and herbal medicines for preventing and managing diseases with a long history in China. Due to its endangered natural resources and huge demand, people tend to cultivate D. huoshanense to protect this species. However, the quality of wild and cultivated herbs of the same species may change. This work quantified and compared the main quality traits and chemical components of wild imitating and greenhouse cultivated D. huoshanense with different growth years. As a result, wild and cultivated D. huoshanense had similar chemical composition, but there are significant differences in the content of many ingredients (polysaccharides, flavonoids, nucleosides, bibenzyls, lignans and volatile compounds). And the contents of many of these components increased with growing years. In addition, multivariate statistical analyses have been applied to classify and evaluate samples from different cultivation modes according to these components. In conclusion, our results demonstrated that the overall quality of greenhouse cultivated D. huoshanense was not as good as wild-grown, but this mode can be a promising and sustainable way of producing D. huoshanense.

Identification of lignans and quality assessment in Dendrobium officinale under different cultivation modes.

RATIONALE: Lignans have attracted much attention from researchers because of their wide distribution and industrial applications in plants, as well as the remarkable diversity of their biological activities. As the literature has mainly focused on the extraction and identification of monomeric compounds of lignans, most lignans in Dendrobium officinale, a traditional Chinese medicine with a long cultivation history and rich sources, have not been detected using quality control methods. The aim of this study was to identify the lignans in Dactilon officinale. METHODS: High-performance liquid chromatography (HPLC) coupled with diode array detection and HPLC multiple-stage tandem mass spectrometry was used to identify the chemical constituents of D. officinale. Simultaneously, the characteristic chromatograms of D. officinale were established. Additionally, a method was established to determine the content of syringaresinol-4,4'-di-O-ß-D-glucoside, syringaresinol-4-O-ß-D-glucoside and syringaresinol. RESULTS: Thirty-three lignans, including 17 tetrahydrofuran lignans, two dibenzylbutane lignans, three aryl tetrahydronaphthalene lignans and 11 8-O-4'-neolignans, were tentatively identified from the methanol extract of the stems of D. officinale. This is the first report of 8-O-4'-neolignans from D. officinale. In addition, a total of eight characteristic peaks were marked in characteristic chromatograms, which were identified as lyoniresinol-9'-O-ß-D-glucoside, syringaresinol-4,4'-di-O-ß-D-glucoside, 8-hydroxy-syringaresinol-4-O-ß-D-glucoside, 5,5'-dimethoxy-lariciresinol-4-O-ß-D-glucoside, syringaresinol-4-O-ß-D-glucoside, 4-hydroxy-3,3',5,5'-tetramethoxy-8,4'-oxyneoligna-7'-ene-9,9'-diol-9-O-ß-D-glucoside, 4-hydroxy-3,3',5,5'-tetramethoxy-8,4'-oxyneoligna-7'-ene-9,9'-diol-4-O-ß-D-glucoside and syringaresinol. Our results showed that no significant difference occurred in lignan composition among the 99 batches of D. officinale from different sources. However, the peak areas of the lignans of D. officinale planted under simulated wild culture were generally higher than those in greenhouses, and showed an upward trend with the increase in growth years. The average contents of syringaresinol-4,4'-di-O-ß-D-glucoside, syringaresinol-4-O-ß-D-glucoside and syringaresinol were 10.112-179.873, 51.227-222.294 and 6.368-120.341 µg/g, respectively. CONCLUSIONS: This study provided a basis for improving the quality control of D. officinale and could provide references for the identification of lignans in other Dendrobium species.

Identification of bibenzyls and evaluation of imitative wild planting techniques in Dendrobium officinale by HPLC-ESI-MSn.

Dendrobium officinale is a traditional Chinese herb with beneficial properties. Modern pharmacological studies show that bibenzyl is one of the antitumor active ingredients, but there is no effective quality control method for identifying ingredients. In this study, the composition of bibenzyls in Dendrobium officinale was studied by high-performance liquid chromatography coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MSn ). A total of nine isolated bibenzyls and their glycosides, 22 bis (bibenzyls), and two phenylpropanol bibenzyl derivatives were identified. The results of HPLC characteristic chromatogram analysis and statistical analysis showed that the relative content of bibenzyls in wild imitation cultivation of samples had been significantly higher than that in greenhouse cultivation. In addition, the relative content of bibenzyls increased with the growth of the original plant. This study provided a scientific reference for controlling the quality of bibenzyls in Dendrobium officinale, developing the cultivation technology and improving the quality of Dendrobium officinale. HIGHLIGHTS: HPLC-ESI-MS/MS method for the analysis of bibenzyls and bis (bibenzyls) in Dendrobium officinale. Easy-to-use method facilitating rapid measurement of large sample quantities. The method requires only small volumes of samples for the analysis. Applicable for the establishment of Chinese medicine studies and the quality control standard of Chinese herbs.

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.

Taxonomic and functional diversity of Dendrobium officinale microbiome in Danxia habitat.

AIMS: Microbial communities that inhabit plants are crucial for plant survival and well-being including growth in stressful environments. The medicinal plant, Dendrobium officinale grows in the barren soils of the Danxia Habitat. However, the microbiome composition and functional potential for growth of this plant in this environment are still unexplored. METHODS AND RESULTS: In this study, we analysed the taxonomic and functional diversity of the D. officinale Microbiome by metagenomic sequencing of both rhizosphere and endosphere samples. A total of 155 phyla, 122 classes, 271 orders, 620 families and 2194 genera were identified from all samples. The rhizospheric microbes (DXRh) were mainly composed of Proteobacteria and Acidobacteria, while Basidiomycota and Ascomycota were the most dominant phyla in root endosphere (DXRo) and stem endosphere (DXS), respectively. Most of the dominant microbial communities had been reported to have diverse functional potentials that can help plant growth and development in stressful and nutrient-deprived ecological environmental. These include plant growth promoting rhizobacteria (PGPR) such as Massilia, Pseudomonas, Bradyrhizobium, Klebsiella, Streptomyces, Leclercia, Paenibacillus, Frankia and Enterobacter in the DXRh, Tulasnella and Serendipita in the DXRo, Colletotrichum and Burkholderia in the DXS and Paraburkholderia, Rhizophagus and Acetobacter in endosphere. Analysis using the KEGG, eggNOG and CAZy databases showed that metabolic pathways such as carbohydrate metabolism, amino acid metabolism, energy metabolism, genetic information processing and environmental information processing are significantly abundant, which may be related to the survival, growth and development of D. officinale in a stressful environment. CONCLUSIONS: We speculated that the microbial community with diverse taxonomic structures and metabolic functions inhabiting in different niches of plants supports the survival and growth of D. officinale in the stressful environment of Danxia Habitat. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided an important data resource for microbes associated with D. officinale and theoretical foundation for further studies.