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Recently, nanoparticles have been widely used in drug and vaccine adjuvant delivery. Dendrobium devonianum Polygonatum (DP), a main biologically active ingredient isolated from Dendrobium devonianum, has been widely used in the clinic as an immunostimulant to stimulate and improve immune responses, contributing to its excellent biological activity. To increase the immune efficacy of DP, macrophage cell membrane-coated drug nanocrystals featuring homologous immune escape, targeting ability and low toxicity are in high demand. In this study, a new drug and vaccine adjuvant delivery system, PEI-MM-PLGA-DP/OVA, was designed and developed. This study aimed to report the macrophage immunomodulatory activity of PEI-modified macrophage cell membrane-coated PLGA nanoparticles encapsulating Dendrobium devonianum polysaccharides. PEI-MM-PLGA-DP/OVA could promote antigen uptake by macrophage and lymphocyte proliferation, increase the expression levels of MHC II, CD80 and CD86, and upregulate the ratio of CD4+ to CD8+ T cells in immunized mice. PEI-MM-PLGA-DP/OVA induced the highest TNF-α, IFN-γ, IL-4, and IL-6 cytokine secretion levels and the levels of OVA-specific antibodies (IgG) compared with the other groups. The above results indicated that PEI-MM-PLGA-DP/OVA had better adjuvant activity than PLGA-DP/OVA and MM-PLGA-DP/OVA.

The discovery of new edible flowers that are nontoxic, innocuous flowers having human health benefits, surveys of their phytochemicals and utilization are of great scientific and commercial interest. Dendrobium officinale and Dendrobium devonianum are precious Traditional Chinese Medicine. During the massive commercial cultivation, a lot of flowers were produced and certified as edible flowers, and the phytochemical profiles and bioactivities warrant evaluate. The present study aimed to investigate the phytochemicals and antioxidative activities in flowers of D. officinale (DOF) and D. devonianum (DDF). In total, 474 metabolites were identified using a widely targeted metabonomics method, 16 amino acids and 6 flavonoids were measured using high‐performance liquid chromatography (HPLC), and 8 fatty acids were detected using gas chromatography–mass spectrometry (GC‐MS). Both flowers contained various amino acids, including 7 essential amino acids, diverse flavonoids, especially quercetin, kaempferol and their derivatives, and high levels of methyl linoleate and methyl linolenate. The relative levels of quercetin, kaempferol and their glycosides were higher in DDF than in DOF, whereas the relative levels of several flavonoids C‐glycosides were high in DOF. Ethanol extracts of both DOF and DDF showed antioxidative capacities including the scavenging of 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals. Both edible flowers contained flavonoids, amino acids, and fatty acids and have antioxidative activities, which should be explored for use in functional foods and pharmaceuticals., Dendrobium officinale and Dendrobium devonianum are precious Traditional Chinese Medicines. During the massive commercial cultivation, a lot of flowers were produced and certified as edible flowers, and the phytochemical profiles and bioactivities warrant evaluate. The present study aimed to investigate the phytochemicals and antioxidative activities in flowers of D. officinale (DOF) and D. devonianum (DDF).Both edible flowers contained flavonoids, amino acids and fatty acids, and have antioxidative activities, which should be explored for use in functional foods and pharmaceuticals.

All orchids maintain an obligate relationship with mycorrhizal symbionts during seed germination. In most cases, germination-enhancing fungi have been isolated from roots of mature plants for conservation and cultivation purposes. To understand the germination biology of Dendrobium devonianum, an over-collected medicinal orchid, the seeds of D. devonianum were inoculated with a fungal strain (FDd1) isolated from naturally occurring protocorms of D. devonianum and two other germination-enhancing fungal strains (FDaI7 and FCb4) from D. aphyllum and Cymbidium mannii, respectively. The fungal strain was isolated from five protocorms of D. devonianum and identified as a species of the genus Epulorhiza. In germination trials, treatments with all of the three fungal strains showed a significant promoting effect on seed germination and protocorm formation, compared with the control treatment (no inoculation). However, FDd1 fungal strain showed the greatest effectiveness followed by FDaI7 and FCb4. For all inoculation and control treatments, seeds developed to protocorms regardless of the presence of illumination, whereas protocorms did not develop to seedlings unless illumination was provided. The results of our manipulative experiments confirmed the hypothesis that mycorrhizae associated with orchid seedlings are highly host-specific, and the degree of specificity may be life stagespecific under in vitro conditions. The specific mycorrhizal symbionts from protocorms can enhance restoration efforts and the conservation of orchids such as D. devonianum.

The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis) have a high medicinal value as a traditional Chinese medicine (TCM). Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC) method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS) method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC) method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently.

Dendrobium devonianum has been used as herbal medicines and nutraceutical products since ancient time in China. However, its chemical composition and pharmacological mechanisms are not fully known. In present studies, by chemical purification and characteristic identification, we discovered a novel polysaccharide from D. devonianum, which was designated as DvP-1 with molecular weights of 9.52 × 104 Da. DvP-1 is a homogeneous heteropolysaccharide consisting of D-mannose and d -glucose in the molar ration of 10.11: 1. The main glycosidic linkages were β-1, 4-Manp, which were substituted with acetyl groups at the O-2, O-3 and/or O-6 positions. DvP-1 was found to directly stimulate the activation of macrophages in vitro, as evidenced by inducing morphologic change, thereby promoting the production of cytokines TNF-α, IL-6 and NO, and enhancing the pinocytic activity of macrophages. By establishing a zebrafish model, we also found that DvP-1 could alleviate vinorelbine-induced decrease of macrophages in vivo. Further findings indicated that DvP-1 activated macrophages through several toll-like receptors (TLRs), but mainly through TLR4. DvP-1 served as a TLR4 agonist and induced ERK, JNK, p38, and IκB-α phosphorylation, suggesting the activation of MAPK and NFκB signaling pathways downstream of TLR4. These findings could help us further understand the immunomodulating effects of D. devonianum in Chinese medicines or health foods for immunocompromised persons. They also show the medicinal value of DvP-1 for the treatment of cancer and infectious diseases caused by TLR4 dysfunction.

Two new phenanthrenes dendrodevonin A and B, two new aliphatic acids dendrodevonic acid A and B, along with ten known compounds, were isolated from the stems of Dendrobium devonianum. The structures of new compounds were elucidated on the basis of MS and NMR spectroscopic data, and single-crystal X-ray diffraction analysis. The cytotoxicities of isolates towards HT-29 cell were discussed, and 4-methoxy-2,7-phenanthrenediol exhibited inhibitory activity compared with other studied compounds.

The aim of the present study is to investigate the antitumor activity and immunostimulatory effect of the water-soluble polysaccharides (DDP) from stem of Dendrobium devonianum in S180 tumor-bearing mice. The mice were divided into 3 groups, and then DDP or Ganoderma lucidum polysaccharides (GLP) dissolved in deionized water were given to the mice at a dose of 200 mg kg−1 for 30 days. DDP, as well as GLP, significantly inhibited the growth of mouse transplantable tumors and promoted spleen indexes, delayed-type hypersensitivity reaction, natural killer cell activity, macrophage phagocytosis and lymphocyte proliferation. Moreover, DDP and GLP increased the colonic acetate, butyrate and total short-chain fatty acid (SCFA) concentrations. These results indicated that oral administration of DDP significantly inhibited the growth of transplanted tumors in S180 tumor-bearing mice by improving specific and non-specific immune responses, as well as increasing colonic SCFAs.

Response surface methodology (RSM) was employed to optimize the conditions for the ultrasonic-assisted extraction (UAE) of polysaccharides from the flowers of Dendrobium devonianum. The optimal conditions for the maximum yields of DDFPs are as follows: an extraction temperature of 63.13°C, an extraction time of 53.10 min, and a water-to-raw material ratio of 22.11 mL/g. Furthermore, three fractions (DDFPs30, DDFPs50, and DDFPs70) were prepared from Dendrobium devonianum flowers polysaccharides (DDFPs) by the stepwise ethanol precipitation method. The DDFPs50 exhibited the highest antioxidant activity compared to the other fractions. The molecular weight, polydispersity, and conformation of these fractions were also characterized. In particular, the monosaccharide composition analysis of the DDFPs indicates that mannose and glucose are the primary components, similar to those of the D. officinale plant. This study provides a rapid extraction technology and essential information for the production of DDFPs, which could be potentially used as healthcare food.

The chain conformation, chemical characters and immunomodulatory activity of polysaccharide from Dendrobium devonianum (DDP) were investigated. Results showed that molecular weights, polydispersity index, radius of gyrations of DDP were 3.99 × 10 5 Da 1.27, 74.1 nm, respectively. By applying the polymer solution theory, the exponent (v) values of 2 > z 1/2 = kM w v was calculated as 0.38, which revealed that DDP existed as a globular shape in aqueous solution, and further confirmed by AFM analysis. Furthermore, the main monosaccharide compositions were Man and Glc with the ratio of 29.61:1.00. Indeed, the main glycosidic linkages were β-1,4-Manp, and substituted with acetyl groups at O-2 and O-3 position. Notably, DDP could promote the immune functions of macrophages including NO release and phagocytosis. Thus, DDP could be explored as a natural immune-stimulating agent in the health and functional food area as well as pharmaceutical industries.

Endophytic fungi are rich in orchids and have great impacts on their host plants. 53 endophytes (30 isolates from Dendrobium devonianum and 23 endophytic fungi from D. thyrsiflorum) were isolated, respectively, from roots and stems of Dendrobium species. All the fungi were identified by way of morphological and/or molecular biological methods. 30 endophytic fungi in D. devonianum were categorized into 11 taxa and 23 fungal endophytes in D. thyrsiflorum were grouped into 11 genera, respectively. Fusarium was the dominant species of the two Dendrobium species in common. Antimicrobial activity of ethanol extract of fermentation broth of these fungi was explored using agar diffusion test. 10 endophytic fungi in D. devonianum and 11 in D. thyrsiflorum exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among 6 pathogenic microbes (Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus). Out of the fungal endophytes isolated from D. devonianum and D. thyrsiflorum, Phoma displayed strong inhibitory activity (inhibition zones in diameter >20 mm) against pathogens. Epicoccum nigrum from D. thyrsiflorum exhibited antibacterial activity even stronger than ampicillin sodium. Fusarium isolated from the two Dendrobium species was effective against the pathogenic bacterial as well as fungal pathogens. The study reinforced the assumption that endophytic fungi isolated from different Dendrobium species could be of potential antibacterial or antifungal resource.

The adapter ligation-mediated allele-specific amplification (ALM-ASA) has been applied to authenticate three valuable Dendrobium species (Dendrobium aphyllum, Dendrobium devonianum and Dendrobium officinale) and their corresponding “Fengdou” foods samples. Three species-specific primers and a universal primer were designed. By using these primers, three amplification products are 198 bp (D. aphyllum), 250 bp (D. devonianum) and 310 bp (D. officinale) in length, which were clearly distinguishable on a 2.0% agarose gel. In addition, no band was observed with other 17 allied Dendrobium species of “Fengdou”. The results showed that ALM-ASA could be used to authenticate not only the three valuable Dendrobium species but related food products such as “Fengdou” foods by simultaneous detection of three-site nucleotide difference on rDNA internal transcribed spacer region.

To obtain seedling growth-promoting fungi is a key step in restoration-friendly cultivation of medicinal Dendrobium species, since there are a large number of functionally-unknown endophytic fungi in the roots of Dendrobium plants.In this study, six functionally-unknown endophytic fungal strains were isolated from roots of D.devonianum using single peleton isolation technology, and used in inoculation experiments to test their effectiveness for seedling growth in D.devonianum.After 90 days of inoculation, comparing with the control treatment, FDdS-1, FDdS-2 and FDdS-4 showed strong pathogenic or fatal effects on seedlings; while, FDdS-12, FDdS-9 and FDdS-5 had different effects on seedling growth.FDdS-5 had significant promoting effects on height, fresh and dry weight, stem diameter and root numbers, while FDdS-9 only had significant promoting effect on seedling height, and FDdS-12 had a negative effect on seedling growth.According to the anatomical features of the inoculated roots, FDdS-5 fungi could infect the velamina of seedlings and the existence of symbiosis pelotons in the cortex cells, suggesting that FDdS-5 is a mycorrhiza fungi of D.devonianum.FDdS-5 and FDdS-9 were identified as Sebacina vermifera and Sebacina sp.by molecular technologies.By using FDdS-5 in the restoration-friendly cultivation of D.devonianum, it could effectively promote seedling growth and shorten the seedling growth periods.The results will aid in reintroduction and cultivation of D.devonianum.

In this study, microwave assisted puffing technology was developed to increase the extraction efficiency of polysaccharides from D. devonianum. Fresh stems of Dendrobium devonianum were processed using microwave puffing technology and the processing conditions were explored and optimized to increase the extraction yield of polysaccharides. The effects of sample length (SL), initial moisture content (IMC), microwave power (MP), and processing time (PT) on quality attributes of the products, in terms of expansion ratio and sensory evaluation, were analyzed using response surface methodology. The optimal SL, IMC, MP, and PT were 3.5 cm, 22%, 702 W, and 31 s, respectively, which resulted in optimal expansion ratio and sensory score of 326.1% and 8.63, respectively. Furthermore, the extraction yield of polysaccharides from the microwave-puffed products was increased by 18.9% compared with that from nonpuffed samples. Antioxidant and anti-hyperglycemic activities of polysaccharides from puffed and nonpuffed D. devonianum were also evaluated and compared. Practical applications We developed a novel microwave assisted puffing technology to increase the extraction efficiency of polysaccharides from D. devonianum. Polysaccharides, the major active components of Dendrobium species, exhibit the potential as an inhibitor, including immunomodulator, antioxidant, anti-tumor and anti-hyperglycemic agent.

From the whole plant of Dendrobium devonianum, a new flavonol glycoside, 5-hydroxy-3-methoxy-flavone-7-O-[β-D-apiosyl-(1 → 6)]-β-D-glucoside, as well as 13 known compounds, was isolated. Their structures were identified based on extensive spectroscopic studies including HR-EI-MS, (1)H, (13)C NMR, DEPT, H-H COSY, HSQC, HMBC and NOESY spectra. The new compound and gigantol were evaluated for their α-glucosidase inhibitory activity, and both displayed more potent α-glucosidase inhibitory activity than acarbose, one of the most potent α-glucosidase inhibitor drugs, with the inhibition rate of 43.4% and 36.7%, respectively, in the concentration of 437.5 μmol/L.

The aim of this study was to establish a method for discriminating Dendrobium officinale from four of its close relatives Dendrobium chrysanthum, Dendrobium crystallinum, Dendrobium aphyllum and Dendrobium devonianum based on chemical composition analysis. We analyzed 62 samples of 24 Dendrobium species. High performance liquid chromatography analysis confirmed that the four low molecular weight compounds 4′,5,7-trihydroxyflavanone (naringenin), 3,4-dihydroxy-4′,5-dime- thoxybibenzyl (DDB-2), 3′,4-dihydroxy-3,5′-dimethoxybibenzyl (gigantol), and 4,4′-dihydroxy-3,3′,5-trimethoxybibenzyl (moscatilin), were common in the genus. The phenol-sulfuric acid method was used to quantify polysaccharides, and the monosaccharide composition of the polysaccharides was determined by gas chromatography. Stepwise discriminant analysis was used to differentiate among the five closely related species based on the chemical composition analysis. This proved to be a simple and accurate approach for discriminating among these species. The results also showed that the polysaccharide content, the amounts of the four low molecular weight compounds, and the mannose to glucose ratio, were important factors for species discriminant. Therefore, we propose that a chemical analysis based on quantification of naringenin, bibenzyl, and polysaccharides is effective for identifying D. officinale.

5 pages; International audience; This article documents the addition of 411 microsatellite marker loci and 15 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Acanthopagrus schlegeli, Anopheles lesteri, Aspergillus clavatus, Aspergillus flavus, Aspergillus fumigatus, Aspergillus oryzae, Aspergillus terreus, Branchiostoma japonicum, Branchiostoma belcheri, Colias behrii, Coryphopterus personatus, Cynogolssus semilaevis, Cynoglossus semilaevis, Dendrobium officinale, Dendrobium officinale, Dysoxylum malabaricum, Metrioptera roeselii, Myrmeciza exsul, Ochotona thibetana, Neosartorya fischeri, Nothofagus pumilio, Onychodactylus fischeri, Phoenicopterus roseus, Salvia officinalis L., Scylla paramamosain, Silene latifo, Sula sula, and Vulpes vulpes. These loci were cross-tested on the following species: Aspergillus giganteus, Colias pelidne, Colias interior, Colias meadii, Colias eurytheme, Coryphopterus lipernes, Coryphopterus glaucofrenum, Coryphopterus eidolon, Gnatholepis thompsoni, Elacatinus evelynae, Dendrobium loddigesii Dendrobium devonianum, Dysoxylum binectariferum, Nothofagus antarctica, Nothofagus dombeyii, Nothofagus nervosa, Nothofagus obliqua, Sula nebouxii, and Sula variegata. This article also documents the addition of 39 sequencing primer pairs and 15 allele specific primers or probes for Paralithodes camtschaticus.