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Four new glucosides, named as gigantol-5-O-β-d-glucopyranoside (1), 9,10-dihydro-aphyllone A-5-O-β-d-glucopyranoside (2), ficusal-4-O-β-d-glucopyranoside (3), botrydiol-15-O-β-d-glucopyranoside (4), together with eight known compounds (5–12) were isolated from then-BuOH extract of the stems ofDendrobium fimbriatumHook. Their structures were elucidated by the analyses of spectroscopic data. [ABSTRACT FROM PUBLISHER]

Epigallocatechin gallate (EGCG) is the most abundant component of green tea catechins and has strong physiological activities. In this study, two novel EGCG glycosides (EGCG-G1 and EGCG-G2) were chemoselectively synthesized by a chemical modification strategy. Each of these EGCG glycosides underwent structure identification, and the structures were assigned as follows: epigallocatechin gallate-4″-O-β-D-glucopyranoside (EGCG-G1, 2) and epigallocatechin gallate-4′,4″-O-β-D-gluco-pyranoside (EGCG-G2, 3). The EGCG glycosides were evaluated for their anticancer activity in vitro against two human breast cell lines (MCF-7 and MDA-MB-231) using MTT assays. The inhibition rate of EGCG glycosides (EGCG-G1 and EGCG-G2) is not obvious. The EGCG glycosides are more stable than EGCG in aqueous solutions, but exhibited decreasing antioxidant activity in the DPPH radical-scavenging assay (EGCG > EGCG-G2 > EGCG-G1). Additionally, the EGCG glycosides exhibited increased water solubility: EGCG-G2 and EGCG-G1 were 15 and 31 times as soluble EGCG, respectively. The EGCG glycosides appear to be useful, and further studies regarding their biological activity are in progress. [ABSTRACT FROM AUTHOR]

Two new bibenzyl derivatives, dendrocandin T (1) and dendrocandin U (2), together with eight known bibenzyls, were isolated from the stems ofDendrobium officinale. Those compounds were sent for the first time for central nervous system-related bioassay and the results indicated that compounds3,4, and5have a certain degree of neurite outgrowth-promoting activity, and compounds1,2,6, and7also have weak activity. The results indicated thatD. officinaleused as health food and traditional Chinese medicine “Tiepi Shihu” has a health function of neurotrophic effects. [ABSTRACT FROM PUBLISHER]

Three new cassane-type diterpenes, 14-dehydroxy-12,16-dihydrocaesaldekarin L ( 1), 1-deacetyl-12-ethoxyneocaesalpin N ( 2), and 1-deacetylneocaesalpin N ( 3), together with two known cassane-type diterpenes, neocaesalpin A and neocaesalpin L, were isolated from the EtOH extract of the twigs and leaves of Caesalpinia minax. Their structures were elucidated by spectroscopic methods, as well as by comparison of their spectral data with those of related compounds. [ABSTRACT FROM AUTHOR]

Three new stilbenoids, 1-(4′-hydroxybenzyl)-imbricatin (1), (E)-4′-hydroxy-2′,3,3′,5-tetramethoxystilbene (2), and (E)-3,4′-dihydroxy-2,6-bis(4-hydroxybenzyl)-2′,3′,5-trimethoxystilbene (3), together with 15 known stilbene derivatives, were isolated from Pholidota yunnanensis. Their structures were elucidated by spectroscopic methods and by comparison of their NMR data with those of related compounds. Furthermore, the inhibitory activities on nitric oxide (NO) production of the isolated compounds were examined in murine macrophages (RAW 264.7) activated by lipopolysaccharide. The cytotoxicity of 18 compounds was determined by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. Among the tested compounds, eight stilbenoids, including three dihydrophenanthrenes, three stilbenes, and one bibenzyl derivative showed inhibitory effects on NO production without cytotoxicity with IC50 values ranging from 4.07 to 7.77 μM, as compared to MG-132, which was used as a positive control (IC50 of 0.10 μM). One dihydrophenanthrene, phoyunnanin C (5), showed cytotoxic effects at the test concentrations. [ABSTRACT FROM AUTHOR]

Two novel bibenzyl trigonopols A (1) and B (2), together with seven known compounds, gigantol (3), tristin (4), moscatin (5), hircinol (6), naringenin (7), 3-(4-hydroxy-3-methoxyphenyl)-2-propen-1-ol (8), and ( - )-syringaresinol (9), have been isolated from the stems of Dendrobium trigonopus, of which compounds 6, 8, and 9 were isolated for the first time from this species. The structures of two new compounds were elucidated as threo-22-(17-hydroxyl-9-(3-hydroxyl-4-methoxy-phenethyl)-13,16,18-trimethoxy-21H-benzo[c]chromen-21-yl)ethane-22, 23-diol (1) and 9-(4-hydroxyl-3-methoxy-phenethyl)-17-(21-hydroxyl-20-methoxy-phenyl)chroman-11, 16-diol (2) on the basis of spectroscopic methods. Trigonopol A was found to exhibit antiplatelet aggregation activity in vitro with 67.55% inhibitory ration at 1.4337 × 10- 3 M. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) as a multifunctional hormone is secreted mainly from enteroendocrine L-cells, and enhancing its endogenous secretion has potential benefits of regulating glucose homeostasis and controlling body weight gain. In the present study, a novel polysaccharide (h-DHP) with high ability to enhance plasma GLP-1 level in mice was isolated from Dendrobium huoshanense protocorm-like bodies under the guidance of activity evaluation. Structural identification showed that h-DHP was an acidic polysaccharide with the molecular weight of 1.38 × 105 Da, and was composed of galactose, glucose, arabinose and glucuronic acid at a molar ratio of 15.7: 11.2: 4.5: 1.0 with a backbone consisting of →5)- α -L-Ara f -(1→, →3)- α -D-Gal p -(1→, →6)- α -D-Gal p -(1→, →3,6)- α -D-Gal p -(1→, →6)- β -D-Glc p -(1→ and →4,6)- β -D-Glc p -(1→ along with branches consisting of α -L-Ara f -(1→, α -D-Gal p -(1→, α -D-GlcA p -(1→, β -D-Glc p -(1→ and →4)- β -D-Glc p -(1→. Animal experiments with different administration routes demonstrated that h-DHP-enhanced plasma GLP-1 level was attributed to h-DHP-promoted GLP-1 secretion in the enteroendocrine L-cells, which was supported by h-DHP-enhanced extracellular GLP-1 level in STC-1 cells. Inhibition of adenylate cyclase and phospholipase C indicated that cAMP and cAMP-triggered intracellular Ca2+ increase participated in h-DHP-promoted GLP-1 secretion. These results suggested that h-DHP has the potential of enhancing endogenous GLP-1 level through h-DHP-promoted and cAMP-mediated GLP-1 secretion from enteroendocrine cells. • An acidic branched polysaccharide (h-DHP) was isolated from Dendrobium huoshanense protocorm-like bodies. • h-DHP could efficiently promoted GLP-1 secretion from enteroendocrine L-cells into the circulation. • h-DHP triggered GLP-1 secretion through cAMP-mediated signaling. [ABSTRACT FROM AUTHOR]

Dry eye is one of the most common ocular surface diseases caused by tear film instability and ocular surface damage due to an abnormal quality or quantity of tears. Inflammatory factors can initiate relevant transduction signalling pathways and trigger the inflammatory cascade response, resulting in ocular surface inflammation. It has been shown that the active ingredients in Dendrobium, such as polysaccharides, alkaloids and phenols, have anti-inflammatory, anti-tumour and immunity-boosting effects, and Dendrobium officinale extract can improve glandular secretion function, increase salivary secretion and increase the expression level of water channel protein in salivary glands in patients with dry eye syndromes. We investigated the in vitro cytoprotective effect of Dendrobium extracts in sodium chloride induced hyperosmotic conditions in human cornea keratocytes (HKs). Results showed that Dendrobium officinale Kimura et Migo water extract (DOW) and Dendrobium loddigesii Rolfe water extract (DLW) could upregulate the expression of aquaporins (AQP)5 protein, thus exerting a repairing effect by promoting cell migration. Furthermore, oral administration of DOW and DLW enhanced tear production in rats and exerted a protective effect on ocular surface damage. DOW and DLW could upregulate the expression of AQP5 and mucin (muc)5ac proteins in the lacrimal gland and reduce the inflammatory response. DOW and DLW inhibited the activation of the corresponding mitogen-activated protein kinases (MAPK) and NF-KB pathway, thereby playing a role in improving dry eye symptoms. This study provides a new perspective on dry eye treatment, and DOW and DLW may be potential therapeutic agents for dry eye. [ABSTRACT FROM AUTHOR]

A novel polysaccharide (MSP-1) was isolated from the fruiting body of Morchella sextelata and purified using DEAE-52 and Sephadex G-75. The molecular weight of MSP-1 was 1.17 × 104 Da, as detected by HPLC analysis. The monosaccharide composition of MSP-1 was mannose and glucose at a ratio of 1.00: 1.25. Methylation and NMR results revealed that the backbone of MSP-1 was composed of →4)- β -D-Man p -(1→, →4)- β -D-Glc p -(1→, →4)- α -D-Glc p -(1→, and →4, 6)- α -D-Glc p -(1→. SEM images of MSP-1 presented a dense network structure with porous characterizations. The immunomodulatory activities of MSP-1 were evaluated using RAW264.7 cells, and the results showed that MSP-1 promoted proliferative and phagocytic activity and increased the production of NO, TNF- α and IL-6. These results indicated that MSP-1 exhibited significant immunomodulatory activities. • A novel heteropolysaccharide (MSP-1) was purified from the fruiting body of Morchella sextelata. • The complete structure of M. sextelata polysaccharide was exhibited for the first time in the present study. • The 3D structure of MSP-1 presented a dense network structure with porous characterizations. • MSP-1 exhibited strong immunomodulatory activities by promoting proliferative and phagocytic activity and obviously increasing the production of NO, TNF- α and IL-6 on RAW264.7 cells. [ABSTRACT FROM AUTHOR]

To explore the active polysaccharides from Dendrobium devonianum , a novel O -acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)- β - d -Man p -(1 → (71.4%) residue with internal →4)-2- O -acetyl- β - d -Manp-(1 → (14.2%), →4)-3- O -acetyl- β - d -Man p -(1 → (7.1%), and non-reducing end β - d -Man p -(1 → (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF- α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials. Structural characterization and biological evaluation of an key O -acetyl-1,4-linked- β - d -mannan from Dendrobium devonianum. [Display omitted] • The fine structure of Dendrobium devonianum polysaccharide was firstly elucidated. • Anticancer assay in vitro revealed that DDP-1 had cytotoxic activity against the growth of HepG2 and MCF-7 cancer cells. • DDP-1 presented remarkable immune-enhancing properties in vitro. • The microstructure features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials. [ABSTRACT FROM AUTHOR]

Background: Nanovaccines have shown the promising potential in controlling and eradicating the threat of infectious diseases worldwide. There has been a great need in developing a versatile strategy to conveniently construct diverse types of nanovaccines and induce potent immune responses. To that end, it is critical for obtaining a potent self-adjuvant platform to assemble with different types of antigens into nanovaccines. Results: In this study, we identified a new natural polysaccharide from the rhizomes of Bletilla striata (PRBS), and used this polysaccharide as a platform to construct diverse types of nanovaccines with potent self-adjuvant property. In the construction process of SARS-CoV-2 nanovaccine, PRBS molecules and RBD protein antigens were assembled into ~ 300 nm nanoparticles by hydrogen bond. For HIV nanovaccine, hydrophobic effect dominantly drove the co-assembly between PRBS molecules and Env expression plasmid into ~ 350 nm nanospheres. Importantly, PRBS can potently activate the behaviors and functions of multiple immune cells such as macrophages, B cells and dendritic cells. Depending on PRBS-mediated immune activation, these self-adjuvant nanovaccines can elicit significantly stronger antigen-specific antibody and cellular responses in vivo, in comparison with their corresponding traditional vaccine forms. Moreover, we also revealed the construction models of PRBS-based nanovaccines by analyzing multiple assembly parameters such as bond energy, bond length and interaction sites. Conclusions: PRBS, a newly-identified natural polysaccharide which can co-assemble with different types of antigens and activate multiple critical immune cells, has presented a great potential as a versatile platform to develop potent self-adjuvant nanovaccines. [ABSTRACT FROM AUTHOR]

Among the diversified glycan modifications, acylation is one of the most abundant. This modification could be responsible for many of the properties of glycans, such as structural stability and specificity for biological activity. To obtain better insight into the effects of acetylation of glycans on the structure and thermostability of insulin, it is critical to investigate glycans with a high degree of acetylation. An in-depth study of three functional glycans named acetyl-mannan from Dendrobium devonianum (DDAM) was conducted herein by efficient enzymatic depolymerization, and the effect of glycosidic bonds on acetylation modification sites was studied through a molecular dynamics (MD) method, as well as its positive effect on insulin secretion, glucose uptake, and the thermal stability of tertiary structures in vitro. Further study indicated that DDAMs play a hypoglycemic role by sparking the thermostability of the insulin conformation. The hypoglycemic activity displayed a positive correlation with the degree of acetylation in DDAMs. In this work, through the MD method, we confirmed the structure characteristics of DDAMs and provided accurate data support for the structure-activity relationship analysis. Thus, these findings demonstrated that DDAMs might be an exceptional leading compound for the stability of insulin drug. • Through the MD method, we have determined the optimal location for acetylation and the structure of natural complex glycan. • After treatment with DDAMs, the mechanism of hypoglycemic may be related to the increased thermostability of the insulin. • The SAR results suggest that the hypoglycemic activity shown a positive correlation with the degree of acetylation in DDAMs. [ABSTRACT FROM AUTHOR]

• Interactions between glycan and lipid soluble molecule (zeaxanthin) are non-covalent. • The mechanism of interaction of zeaxanthin and corn silk glycans was enthalpy driven. • The interaction proved a positive role in hypoglycemic effect and the nutrient base. • The mechanism of hypoglycemic related to the thermostability of insulin and glycans. Glycans in corn silk could interact with co-existing small molecules during its absorption, digestion, and biological process. In order to understand the exact mechanism of action of zeaxanthin, it is critical to investigate the biomolecular interactions, which were necessary to form a glycan-small molecule complex and yet produce the bioactive effect. So far, the in-depth study of these natural interactions has not been fully elucidated. Here, we probed that the molecular interaction between zeaxanthin (ZEA) and glycans from corn silk (CSGs) was driven by enthalpy. More importantly, it was the first time found that CSGs can bind to lipid-soluble ZEA could be binded with CSGs. It was the first report on the thermostability of insulin structure and natural glycans. This study should facilitate our understanding of the interaction between lipid soluble molecules and glycans, and provide a more comprehensive understanding of the nutrient base in food. [ABSTRACT FROM AUTHOR]

Glycans play a crucial role in a variety of physiological and pathological processes. In terms of skin, the sugar chain length, monosaccharide composition and structure of glycans change with age, and thus the changes in glycogens in skin cells are a potential biomarker of aging. The exogenous addition of structurally defined glycans is of great importance for delaying the skin aging process. Fortunately, a functional glycan named manno-oligosaccharide (DOMOS) from Dendrobium officinale was obtained herein by efficient enzymatic depolymerization and exerts anti-aging effects on human skin in vitro and in vivo together with human clinical studies. Further studies show that DOMOS exerts anti-aging effects by triggering the ECM process through a TGF- β /Smad-SIRT1 signalling pathway. This is the first study to concentrate on the beneficial effects of glycan degradation by a highly specific method on skin aging and provides an all-new solution to the skin aging problem that people are most concerned about. [Display omitted] [ABSTRACT FROM AUTHOR]

The traditional Chinese medicine (TCM) "Shihu" has a long history of medicinal use in China from some species of Dendrobium. D. officinale is a major source of "Shihu" and is widely cultivated in south of China and listed separately as "Tiepi Shihu" by the Chinese Pharmacopoeia in now time. Traditionally, D. officinale has been widely used in daily health care and the treatment of diabetes and gastrointestinal diseases. In order to better develop and utilize D. officinale , we conducted this systematic review of previous studies, showed clear structure of all isolates from D. officinale together with pharmacological progress, hoping to provide references for further research and utilization. In addition, specific display of the chemical components and the research progress of related activities can help to better understand the traditional records and modern pharmaceutical applications of the plant medicine. Information on phytochemistry and pharmacological studies of D. officinale was collected from various scientific databases including Web of Science, SciFinder, ACS, Springer, Scopus, PubMed, ScienceDirect, Google Scholar and CNKI. More than 180 compounds isolated from D. officinale , including bibenzyls, phenols, phenylpropanoids, lignans, flavonoids and polysaccharides are listed in this review. Furthermore, modern pharmacological researches such as hypoglycemia, immune regulation, antioxidant, cardiovascular regulation and gastrointestinal protection are summarized. Based on the summary of the research work of D. officinale , we systematically show the chemical composition of the plant, and concluded the relationship of those composition with plant habitat together with the relationship between the structure of chemical components and pharmacological activity. Moreover, we suggest that some of small molecule compounds could also be quality control of D. officinale besides polysaccharides. [Display omitted] • D. officinale is widely used in Asia as a precious folk herbal medicine or health food. • Traditional application of D. officinale and modern diseases, especially diabetes, were discussed. • Active ingredients and their action mechanism of D. officinale were systematically summarized. • The relationship between habitat and chemical composition of D. officinale was discussed. • This review intends to provide a comprehensive understanding and appraisal of D. officinale. [ABSTRACT FROM AUTHOR]

Twenty-one compounds (nine iridoids and twelve sesquiterpenoids), including ten previously unknown (five iridoids and five sesquiterpenoids) were isolated from whole dried material of Valeriana stenoptera . Structures were established on the basis of extensive spectroscopic analysis and the relative stereochemistry of 13-hydroxypatchoulol A was further confirmed by X-ray crystallographic data. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells and seven compounds showed potent promoting effects. [ABSTRACT FROM AUTHOR]

Three new iridoids, jatamanvaltrates R–S ( 1 – 2 ) and jatamanin Q ( 3 ), as well as three new sesquiterpenoids, valeriananoids D–E ( 4 , 5 ) and clovane-2 β -isovaleroxy-9 α -ol ( 6 ), together with nine known compounds were isolated from the roots of Valeriana jatamansi Jones. Compound 2 was the first reported iridoid with fatty acid esters in the Valerianaceae family. The structures of new compounds were established on the basis of extensive spectroscopic analysis. Moreover, all the isolates were evaluated for inhibitory activity on acetylcholinesterase (AChE). [ABSTRACT FROM AUTHOR]