Structural characterization and antioxidant activity of a low-molecular polysaccharide from Dendrobium huoshanense

Structural characterization and improves cognitive disorder in ageing mice of a glucomannan from Dendrobium huoshanense

In the present work, a neutral polysaccharide (DHP-2W) with attenuating cognitive disorder was identified from Dendrobium huoshanense and its structure was clarified. The polysaccharide was successfully purified from D. huoshanense by column chromatography and its activity was evaluated. With a molecular weight of 508.934kDa, this polysaccharide is composed of mannose and glucose at a molar ratio of 75.81: 24.19. Structural characterization revealed that DHP-2W has a backbone consisting of 4)-β-D-Manp-(1 and 4)-β-D-Glcp-(1. In vivo experiments revealed that DHP-2W improved cognitive disorder in D-galactose treated mice and relieved oxidative stress and inflammation. DHP-2W attenuates D-galactose-induced cognitive disorder by inhibiting the BCL2/BAX/CASP3 pathway and activating the AMPK/SIRT pathway, thereby inhibiting apoptosis. Furthermore, DHP-2W had a significant effect on regulating the serum levels of Flavin adenine dinucleotide, Shikimic acid, and Kynurenic acid in aged mice. These, in turn, had a positive impact on AMPK/SIRT1 and BCL2/BAX/CASP3, resulting in protective effects against cognitive disorder.

Complete composition analysis of polysaccharides based on HPAEC-PAD coupled with quantitative analysis of multi-components by single marker

INTRODUCTION

Monosaccharide compositions analysis (MCA) is indispensable for structural characterisations and structure-activity relationships of plant polysaccharides.

OBJECTIVES

To develop a concise and direct MCA method, we established a quantitative analysis of the multi-monosaccharaides by single marker (QAMS) by high-performance anion-exchange chromatography with pulsed-amperometric detection (HPAEC-PAD) method.

METHODOLOGY

A stable and reproducible HPAEC-PAD method for simultaneous determination of aldoses, ketoses and uronic acids (i.e., l-arabinose, d-xylose, d-ribose, l-rhamnose, d-fucose, d-mannose, d-glucose, d-galactose, d-fructose, d-glucuronic acid and d-galacturonic acid) was established by systematic optimisation of stationary phases, column temperatures and elution programmes. On this basis, the QAMS method was proposed through comprehensive investigations of relative correction factor (RCF) variations under different influencing factors, for example, sample concentrations, flow rates, and column temperatures.

RESULTS

Using rhamnose as an internal reference standard, the contents of the other monosaccharide components in polysaccharides from Panax quinquefolium L. and Achyranthes bidentata Bl. samples were simultaneously determined by QAMS, and there was no significant difference between the results from the QAMS and external standard method (t test, P > 0.520). In addition, a MCA fingerprinting of 30 batches of P. quinquefolium polysaccharide was established by HPAEC-PAD, and six common peaks were assigned and determined.

CONCLUSIONS

The established HPAEC-PAD-QAMS method was successfully applied to the MCA of polysaccharides from P. quinquefolium and A. bidentata after optimisation of hydrolysis conditions. HPAEC-PAD-QAMS was proposed and established for MCA of plant polysaccharides for the first time.

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.

Purification, structure identification and immune activity of a neutral polysaccharide from Cynanchum Auriculatum

The crude polysaccharides CAPS and CAP of Cynanchum Auriculatum, which were prepared by degrading starch by single-enzymatic method (α-amylase) and double-enzymatic method (α-amylase and glucoamylase) respectively, were compared. CAP had good water solubility and higher non-starch polysaccharide content. A homogeneous neutral polysaccharide CAPW, with the degree of acetylation about 17 %, was obtained from CAP by anion exchange column chromatography. Its detailed structure was identified by various methods. CAPW, with the weight average molecular weight of 8.4 kDa, was composed of mannose, glucose, galactose, xylose, and arabinose in a molar ratio of 1.27:1.00:0.25:0.10:1.16. The backbone included β-1,4-Manp, β-1,4,6-Manp, β-1,4-Glcp and β-1,4,6-Glcp residues, with branches at the O-6 position of β-1,4,6-Manp and β-1,4,6-Glcp residues, consisting of α-T-Araf, α-1,5-Araf, α-1,2,5-Araf, α-1,3,5-Araf, T-Xylp,1,4-Xylp, β-T-Manp and β-T-Galp residues. In vitro immunological experiments suggested that CAP-W improved the phagocytic ability of macrophages, stimulated the release of NO, TNF-α and IL-6 from RAW264.7 cells, promoted the expression of NF-κB and caused nuclear translocation of NF-κB p65.

An efficient mixed enzymes-assisted mechanical bio-extraction of polysaccharides from Dendrobium officinale and determination of monosaccharides by HPLC-Q-TOF/MS

The mixed enzymes-assisted mechanical bio-extraction method was first used to extract polysaccharides from Dendrobium officinale. Different parameters including the ratio of enzyme, the amount of enzyme, the grinding time, the extraction time and the solid/liquid ratio were investigated by single factor experiments and multifactorial experiments. Through the response surface methodology the optimal extraction conditions were obtained with the ratio of cellulase to pectinase was 2: 1 and total amount of enzyme was 0.23 mg, the grinding time of 11.48 min, the extraction time of 5.99 min. The obtained polysaccharide extracts were hydrolyzed and derivatized and then injected into high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF/MS) for monosaccharide composition analysis. After optimization of the chromatographic conditions (including mobile phase and column), twelve monosaccharides were successfully determined within 20 min. The proposed method provided satisfactory linearity with the correlation coefficients higher than 0.99, suitable recoveries (81.46-114.92 %), acceptable reproducibility ranging from 0.06 % to 4.77 %, low limits of detection (0.70-45.45 ng/mL). Compared with other methods, this method makes the extraction efficiency much higher and has the advantages of simple operation, environmental friendliness and mild extraction conditions. Therefore, this method can be used for the extraction of polysaccharides from plants and the determination of monosaccharides and has the potential to be used in more areas.

Dendrobium and its active ingredients: Emerging role in liver protection

Dendrobium is a traditional medicinal plant, which has a variety of clinical applications in China. It has been reported that Dendrobium contains various bioactive components, mainly including polysaccharides and alkaloids. Previous studies have shown that Dendrobium has pharmacological activities including antiviral, anti-inflammatory, and antioxidant effects, as well as immune regulation. Particularly, the anti-aging functions and neuroprotective effects of Dendrobium have been well characterized in a wide array of cell and animal models. In recent years, the effect of Dendrobium on the liver has emerged as a new direction to explore its therapeutic benefits and has received more and more attention. This review is focused on the beneficial effects of Dendrobium on liver toxicity and various liver disorders, which presumably are attributed to a consequence of an array of modes of action due to its multiple bioactive components, and largely lack mechanistic and pharmacokinetic characterization. A particular emphasis is placed on the potential action mechanisms related to Dendrobium's liver protection. Research perspectives in regard to the potential therapeutic application for Dendrobium are also discussed in this review.

Dendrobium huoshanense C.Z.Tang et S.J.Cheng: A Review of Its Traditional Uses, Phytochemistry, and Pharmacology

Dendrobium huoshanense, a traditional medicinal and food homologous plant, belongs to the family Orchidaceae and has a long history of medicinal use. It is reported that the stem of D. huoshanense has a variety of bioactive ingredients such as polysaccharides, flavonoids, sesquiterpenes, phenols, etc. These bioactive ingredients make D. huoshanense remarkable for its pharmacological effects on anti-tumor, immunomodulation, hepatoprotective, antioxidant, and anticataract activities. In recent years, its rich pharmacological activities have attracted extensive attention. However, there is no systematic review focusing on the chemical compositions and pharmacological effects of D. huoshanense. Therefore, the present review aims to summarize current research on the chemical compositions and pharmacological activities of D. huoshanense. This study provides valuable references and promising ideas for further investigations of D. huoshanense.

Comparative Proteome and Phosphoproteome Analyses Reveal Different Molecular Mechanism Between Stone Planting Under the Forest and Greenhouse Planting of Dendrobium huoshanense

The highly esteemed Chinese herb, Dendrobium huoshanense, whose major metabolites are polysaccharides and alkaloids, is on the verge of extinction. The stone planting under the forest (SPUF) and greenhouse planting (GP) of D. huoshanense are two different cultivation methods of pharmaceutical Dendrobium with significantly differences in morphology, metabolites content and composition, and medication efficacy. Here, we conducted proteomics and phosphoproteomics analyses to reveal differences in molecular mechanisms between SPUF and GP. We identified 237 differentially expressed proteins (DEPs) between the two proteomes, and 291 modification sites belonging to 215 phosphoproteins with a phosphorylation level significantly changed (PLSC) were observed. GO, KEGG pathway, protein domain, and cluster analyses revealed that these DEPs were mainly localized in the chloroplast; involved in processes such as posttranslational modification, carbohydrate transport and metabolism, and secondary metabolite biosynthesis; and enriched in pathways mainly including linoleic acid metabolism, plant-pathogen interactions, and phenylpropanoid, cutin, suberin, and wax biosynthesis. PLSC phosphoproteins were mainly located in the chloroplast, and highly enriched in responses to different stresses and signal transduction mechanisms through protein kinase and phosphotransferase activities. Significant differences between SPUF and GP were observed by mapping the DEPs and phosphorylated proteins to photosynthesis and polysaccharide and alkaloid biosynthesis pathways. Phosphorylation characteristics and kinase categories in D. huoshanense were also clarified in this study. We analyzed different molecular mechanisms between SPUF and GP at proteomic and phosphoproteomic levels, providing valuable information for the development and utilization of D. huoshanense.

Structural characterization of a mannoglucan polysaccharide from Dendrobium huoshanense and evaluation of its osteogenesis promotion activities

Dendrobium huoshanense, a valuable traditional Chinese herb, is widely used to prolong life in China. Our study aims to characterize the structure and osteogenesis-promotion effects of a heteropolysaccharide component isolated from Dendrobium huoshanense (DHPW1). The structure of DHPW1 was characterized using gas chromatography-mass spectrometry and nuclear magnetic resonance, while its osteogenic activity was evaluated using MG-63 cells and zebrafish skulls. The results showed that the molecular weight of DHPW1 was 230 kDa and it was mainly composed of mannose and glucose. In addition, the DHPW1 backbone consisted of (1 → 4)-linked-β-D-Mannopyranosyl and (1 → 4)-linked-β-d-Glucopyranosyl. Furthermore, DHPW1 significantly increased ALP activity and mineralized nodule formation in MG-63 cells. DHPW1 in zebrafish skull models significantly enhanced the relative fluorescence intensity of bone mass and increased the degree of bone mineralization. These results suggested that the DHPW1 component in D. huoshanense has potential to promote osteogenesis.

Structure and Bioactivities of a Novel Polysaccharide Extracted From Dendrobium huoshanense by Subcritical Water

In this study, the polysaccharide was extracted by subcritical water from Dendrobium huoshanense. A novel polysaccharide (DHPs-1) was obtained through several purification steps and its structure and bioactivity were investigated. Structural analysis indicated that the weight-average molecular weight of DHPs-1 was 5.0 × 10⁴ Da and it was mainly composed of glucose (65.04%), mannose (14.23%), galactose (8.17%), galacturonic acid (6.41%), rhamnose (2.34%), and xylose (1.25%). 1,4-Glcp, and 1,4,6-Galp were existed in the backbone of DHPs-1. The residues of 1,3,4-Galp, 1,4-Manp, 1,4-Galp, and 1,3,4,6-Galp could be in the backbone or the side chains with the non-reducing terminal of α-Manp. Bioactivity tests indicated that DHPs-1 had immunomodulatory activity in that it significantly enhanced transcript levels of cytokines [Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), and Interleukin-10 (IL-10)]. DPPH and hydroxyl radical scavenging tests showed that it had good antioxidant activity. These results reveal that DHPs-1 could be developed as a safe immunomodulatory agent and antioxidant for pharmacological or functional food applications.

Huoshanmycins A‒C, New Polyketide Dimers Produced by Endophytic Streptomyces sp. HS-3-L-1 From Dendrobium huoshanense

Three new polyketide dimers named huoshanmycins A‒C (1–3) were isolated from a plant endophytic Streptomyces sp. HS-3-L-1 in the leaf of Dendrobium huoshanense, which was collected from the Cultivation base in Jiuxianzun Huoshanshihu Co., Ltd. The dimeric structures of huoshanmycins were composed of unusual polyketides SEK43, SEK15, or UWM4, with a unique methylene linkage. Their structures were elucidated through comprehensive 1D-/2D-NMR and HRESIMS spectroscopic data analysis. The cytotoxicity against MV4-11 human leukemia cell by the Cell Counting Kit-8 (CCK8) method was evaluated using isolated compounds with triptolide as positive control (IC₅₀: 1.1 ± 0.4 μM). Huoshanmycins A and B (1, 2) displayed moderate cytotoxicity with IC₅₀ values of 32.9 ± 7.2 and 33.2 ± 6.1 μM, respectively.

Integration of Transcriptome and Metabolome Provides New Insights to Flavonoids Biosynthesis in Dendrobium huoshanense

Dendrobium huoshanense is both a traditional herbal medicine and a plant of high ornamental and medicinal value. We used transcriptomics and metabolomics to investigate the effects of growth year on the secondary metabolites of D. huoshanense stems obtained from four different years of cultivation. In this study, a total of 428 differentially accumulated metabolites (DAMs) and 1802 differentially expressed genes (DEGs) were identified. The KEGG enrichment analysis of DEGs and DAMs revealed significant differences in "Flavonoid biosynthesis", "Phenylpropanoid biosynthesis" and "Flavone and flavonol biosynthesis". We summarize the biosynthesis pathway of flavonoids in D. huoshanense, providing new insights into the biosynthesis and regulation mechanisms of flavonoids in D. huoshanense. Additionally, we identified two candidate genes, FLS (LOC110107557) and F3'H (LOC110095936), which are highly involved in flavonoid biosynthesis pathway, by WGCNA analysis. The aim of this study is to investigate the effects of growth year on secondarily metabolites in the plant and provide a theoretical basis for determining a reasonable harvesting period for D. huoshanense.

Simultaneous Quantification of 11 Phenolic Compounds and Consistency Evaluation in Four Dendrobium Species Used as Ingredients of the Traditional Chinese Medicine Shihu

The interchangeable use of different herbs to prepare the same formulation is a common practice in Traditional Chinese Medicine (TCM). However, this practice would require the component herbs to share similar compositions, at least in terms of the bioactive agents, to ensure they can replace each other in drug preparation. In this study, we developed an effective and comprehensive high-performance liquid chromatography-diode array detector (HPLC-DAD) method for simultaneous analysis of 11 phenolic compounds in the methanol extracts of Dendrobium huoshanense, Dendrobium nobile (D. nobile), Dendrobium chrysotoxum (D. chrysotoxum), and Dendrobium fimbriatum (D. fimbriatum), which have been identified as interchangeable ingredients for the same TCM preparation "Shihu" in the Chinese pharmacopeia (ChP). The consistency of the four Dendrobium species was evaluated on the basis of the presence of the 11 investigated compounds and the HPLC fingerprints of the methanol extracts of the plants. When gradient elution was performed with a solvent system of acetonitrile and water on a Zorbax Eclipse XDB-C18 (150 mm × 4.6 mm, 5 μm) with monitoring at 220 nm, all 11 investigated compounds were isolated at the baseline. The established HPLC method showed excellent linearity (all analytical curves showed relative coefficients [R²] > 0.999), sensitivity, precision (relative standard deviation [RSD] < 2%), and accuracy (recovery, 90.65-99.17%). These findings confirmed that the method we constructed was reliable. Quantification analysis showed significant differences in the contents of the investigated polyphenols in the four Dendrobium species. Evaluations of consistency revealed that the similarities among the four species were 0.299-0.906 in assessments based on the 11 polyphenols and 0.685-0.968 in assessments based on HPLC fingerprints. Thus, the components of the four Dendrobium species may be significantly different, and more experiments are required to determine whether they can be used interchangeably in the same amounts for preparing the formulation according to ChP.

A dandelion polysaccharide and its selenium nanoparticles: Structure features and evaluation of anti-tumor activity in zebrafish models

In this study, an inulin fructan (TMP50-2) with moderate anti-tumor activity was obtained from dandelion. To further improve the anti-tumor activity of TMP50-2, a monodisperse and stable spherical nanoparticle (Tw-TMP-SeNP, 50 nm) was fabricated. Physico-chemical analysis revealed that TMP50-2 and Tween 80 were tightly wrapped on the surface of SeNPs by forming CO⋯Se bonds or through hydrogen bonding interaction (OH⋯Se). In vitro anti-tumor assay showed that Tw-TMP-SeNP treatment could significantly inhibit the proliferation of cancer cells (HepG2, A549, and HeLa) in a dose-dependent manner, while HepG2 cells were more susceptible to Tw-TMP-SeNP with an IC₅₀ value of 46.8 μg/mL. The apoptosis induction of HepG2 cells by Tw-TMP-SeNP was evidenced by increasing the proportion of apoptotic cells ranging from 12.5% to 27.4%. Furthermore, in vivo zebrafish model confirmed the anti-tumor activity of Tw-TMP-SeNP by inhibiting the proliferation and migration of tumor cells as well as the angiogenesis of zebrafish embryos.

Dendrobium huoshanense Polysaccharides Prevent Inflammatory Response of Ulcerative Colitis Rat through Inhibiting the NF-κB Signaling Pathway

The polysaccharides of the Chinese herbal medicine Dendrobium huoshanense exhibit anti-inflammatory effects in multiple organs through regulating the immune responses. In the present study, we constructed ulcerative colitis (UC) model rats using dextran sulfate sodium to investigate the anti-inflammatory effects of D. huoshanense polysaccharides (DHP). After oral administration of DHP for two weeks, the indices of UC symptoms, including the ratio of colon weight to length, Disease Activity Index (DAI), and Colon Mucosal Damage Index (CMDI), all decreased significantly compared with the UC model group. The histological sections also revealed better cell orders in DHP treatments than in the UC model rats. Moreover, in treatment with high dose of DHP (200 mg/kg), the treatment efficacy arrived the similar levels to those in the treatment with 300 mg/kg sulfasalazine, which is a typical medicine to treat UC. These results indicated that DHP has a high efficacy to treat UC in model rats. Furthermore, serum levels of interleukin-1β, tumor necrosis factor-α, interleukin-17, and transforming growth factor-β were assessed using the enzyme linked immunosorbent assay (ELISA) method, and the levels of nuclear factor-κB in colon tissue sections were determined using the immunohistochemical method. The results showed that all these indices decreased significantly after administration of DHP in UC model rats, which might be the mechanisms underlying the DHP-suppressed UC inflammation. Overall, this study indicated that DHP might be directly used to treat UC and is a promising source to develop novel drugs against UC.

Merging Reagent Modulation and Remote Anchimeric Assistance for Glycosylation: Highly Stereoselective Synthesis of α-Glycans up to a 30-mer

The efficient synthesis of long, branched, and complex carbohydrates containing multiple 1,2-cis glycosidic linkages is a long-standing challenge. Here, we report a merging reagent modulation and 6-O-levulinoyl remote anchimeric assistance glycosylation strategy, which is successfully applied to the first highly stereoselective synthesis of the branched Dendrobium Huoshanense glycans and the linear Longan glycans containing up to 30 contiguous 1,2-cis glucosidic bonds. DFT calculations shed light on the origin of the much higher stereoselectivities of 1,2-cis glucosylation with 6-O-levulinoyl group than 6-O-acetyl or 6-O-benzoyl groups. Orthogonal one-pot glycosylation strategy based on glycosyl ortho-alkynylbenzoates and ortho-(1-phenylvinyl)benzoates has been demonstrated in the efficient synthesis of complex glycans, precluding such issues as aglycon transfer inherent to orthogonal one-pot synthesis based on thioglycosides.

Purification and Structural Characterization of Dendrobium officinale Polysaccharides and Its Activities

In this study, Dendrobium officinale polysaccharide (named DOPS-1) was isolated from the stems of Dendrobium officinale by hot-water extraction and purified by using Sephadex G-150 column chromatography. The structural characterization, antioxidant and cytotoxic activity were carried out. Based on the results of HPLC, GC, Congo red experiment, together with periodate oxidation, Smith degradation, SEM, FT-IR, and NMR spectral analysis, it expressed that DOPS-1 was largely composed of mannose, glucose and galacturonic acid in a molar ratio of 3.2 : 1.3 : 1. The molecular weight of DOPS-1 was 1530 kDa and the main chain was composed of (1→4)-β-D-Glcp, (1→4)-β-D-Manp and 2-O-acetyl-(1→4)-β-D-Manp. The measurement results of antioxidant activity showed that DOPS-1 had the strong scavenging activities on hydroxyl radicals, DPPH radicals and superoxide radicals and the high reducing ability in vitro. Moreover, DOPS-1 was cytotoxic to all three human cancer cells of MDA-MB-231, A549 and HepG2.

Gigantol Attenuates the Metastasis of Human Bladder Cancer Cells, Possibly Through Wnt/EMT Signaling

BACKGROUND

Bladder cancer has long been recognized as one of the most common and aggressive human malignant carcinomas due to the increased invasiveness and metastasis. The discovery and development of natural compounds from Dendrobium species for cancer therapy have garnered increasing attention in recent years. Among those natural elements, the bibenzyl compound gigantol has promising therapeutic potential against several cancer cell lines; however, its roles on bladder tumor metastasis have not been investigated.

MATERIALS AND METHODS

Here in this in vitro study, we utilized viability tests, cell migration, cell invasion and apoptosis assays to evaluate the anti-tumor activity of gigantol on three human bladder cancer cell lines (SW780, 5637, and T24) and a normal human bladder cell line (SVHUC-1). Cells were treated with different concentrations of gigantol (0, 40, 80, and 160 µM) for 24, 48 and 72 h.

RESULTS

Here in this study, we showed that gigantol suppressed cancer cell proliferation but not normal SVHUC-1 cells. The inhibitory effect of the compound on cell migration and invasion was also exhibited in the cancer cell lines. Cell apoptosis assay by flow cytometry revealed enhanced apoptotic effects of gigantol on cancer cells. Gene expression analysis revealed that Wnt/EMT signaling might involve in the response of bladder cancer cells to gigantol.

CONCLUSION

Therefore, the present data demonstrate gigantol as a strong anticancer reagent against bladder cancer possibly through Wnt/EMT signaling.

The feeding of dietary Codonopsis pilosula polysaccharide enhances the immune responses, the expression of immune-related genes and the growth performance of red swamp crayfish (Procambarus clarkii)

Polysaccharides have many functions in aquatic animals and are widely used as immunopotentiators. However, despite the emergence of serious diseases, few studies have explored the effects of Codonopsis pilosula polysaccharide (CPP) on crustaceans. We studied the effects of CPP on the growth performance, nonspecific immunity, antioxidant activity and disease resistance of red swamp crayfish (Procambarus clarkii). Healthy crayfish (5.80 ± 0.1 g) were fed diets supplemented with 0% (control), 0.05%, 0.1%, 0.15%, 0.20%, and 0.30% CPP for 8 weeks. At the end of the 8-week feeding trial, the optimal final body weight (FBW), weight gain (WG), specific growth rate (SGR), and feed conversion ratio (FCR) were observed in the crayfish fed the diets with 0.15% and 0.20% CPP, followed by those fed the diet with 0.30% CPP and then those fed the diet with 0.10% CPP, whereas the values of these parameters were obtained with the control crayfish (P < 0.05). The crayfish fed the diets with 0.15% and 0.20% CPP exhibited a significantly higher total hemocyte count (THC) and significantly increased phenoloxidase (PO), lysozyme (LZM), hemocyte (Hc), acid phosphatase (ACP) and alkaline phosphatase (AKP) compared with those belonging to the other groups (P < 0.05). The crayfish fed the diets with 0.15% and 0.2% CPP exhibited significantly higher total superoxide dismutase (T-SOD) and glutathione peroxidase (GPx) activities, a significantly increased total antioxidant capacity (T-AOC) and a significantly lower malondialdehyde (MDA) content compared with the other groups (P < 0.05), which indicated that antioxidant capacity was significantly induced by the CPP-supplemented diets. Significantly upregulated expression of immune-related genes (anti-lipopolysaccharide factors (alf), peroxiredoxin (prx5), cathepsin B (ctsb), mitochondrial manganese superoxide dismutase (mtMnsod), cyclophilin A (cypa), glutathione peroxidase (gpx), Toll-like receptor 3 (tlr3), and heat shock protein 70 (hsp70)) was detected in the crayfish fed the diets supplemented with 0.15% and 0.20% CPP diet compared with the levels observed in the control crayfish. These results showed that dietary CPP supplementation greatly improved the growth, immunity and antioxidant capacities of crayfish, and according to the observed results, 0.15%-0.2% is the recommended optimal level of CPP dietary supplementation for crayfish.

A review of isolation methods, structure features and bioactivities of polysaccharides from Dendrobium species

Dendrobium, orchid, is a traditional Chinese herb medicine applied extensively as tonic and precious food for thou-sands of years recorded in ancient Chinese medical book "Shen Nong's Materia Medica". It's well known that bioactivities are usually related to the ingredients' basis. Based on the previous research, Dendrobium species contain amino acid, sesquiterpenoids, alkaloids and polysaccharides. As the bioactive substances, carbohydrate shows extensive activities in antitumor, antiglycation, immune-enhancing, antivirus, antioxidant, antitumor and etc. Therefore, as the main biologically active substance, the exact structures and latent activities of polysaccharides from Dendrobium species are widely focused on. In this review, we focus on the advancements of extraction methods and diversity of structures and bioactivities of polysaccharides obtained from Dendrobium species.

Protective Activities of Dendrobium huoshanense C. Z. Tang et S. J. Cheng Polysaccharide against High-Cholesterol Diet-Induced Atherosclerosis in Zebrafish

Cardiovascular disease is the highest cause of death, and atherosclerosis (AS) is the primary pathogenesis of many cardiovascular diseases. In this study, we aim to investigate the possible pharmaceutical effects of Dendrobium huoshanense C. Z. Tang et S. J. Cheng polysaccharide (DHP) in AS. We fed zebrafish with high-cholesterol diet (HCD) to establish a zebrafish AS model and treated with DHP and observed plaque formation and neutrophil counts under a fluorescence microscope. Next, a parallel flow chamber was utilized to establish low shear stress- (LSS-) induced endothelial cell (EC) dysfunction model. We observed that DHP significantly improved HCD-induced lipid deposition, oxidative stress, and inflammatory response, mainly showing that DHP significantly increased superoxide dismutase (SOD) activity, decreased plaque formation, and decreased neutrophil recruitment and the levels of total cholesterol (TC), triglyceride (TG), malondialdehyde (MDA), and reactive oxygen species (ROS). Furthermore, DHP significantly improved LSS-induced oxidative stress and EC dysfunction. Our results indicated that DHP can exert treatment effects on AS, which may attribute to its hypolipidemic, antioxidant, anti-inflammatory activities and improving LSS-induced EC dysfunction. DHP has promising potential for further development as a functional natural medicine source targeted at AS prevention.

Structural characterization of polysaccharides with potential antioxidant and immunomodulatory activities from Chinese water chestnut peels

Chinese water chestnut peels are a kind of vegetable processing waste containing many active components such as polysaccharides, the structure of which remains unknown. To elucidate the structure of polysaccharides from Chinese water chestnut peels, two polysaccharides named WVP-1 and WVP-2 were isolated. WVP-1 (3.16 kDa) consisted of mannose (1.75 %), glucose (84.69 %), galactose (6.32 %), and arabinose (7.24 %), while WVP-2 (56.97 kDa) was composed of mannose (3.18 %), rhamnose (1.52 %), glucuronic acid (1.42 %), galacturonic acid (4.83 %), glucose (11.51 %), galactose (36.02 %), and arabinose (41.53 %). Linkage and NMR data indicated that WVP-1 was composed mainly of →4)-α-d-Glcp(1→ and a certain proportion of →3)-β-d-Glcp-(1→, including linear and branched polysaccharides simultaneously. WVP-2 was a pectin-like polysaccharide with →4)-α-d-GalpA6Me-(1→ units and the branch points of →3,4)-α-l-Arap-(1→, →3,6)-β-d-Galp-(1→. WVP-2 exhibited stronger potential antioxidant and immunomodulatory activities than WVP-1 in vitro. These results provide a foundation for the further study of polysaccharides from Chinese water chestnut peels.

Chemical modifications of polysaccharides and their anti-tumor activities

With the rising trend of incidence of cancers, effective therapies are urgently needed to control human malignancies. However, the chemotherapy drugs currently on the market cause serious side effects. Polysaccharides belong to a class of biomacromolecules, which have drawn considerable research interest over the years as it possess anti-cancer activities or can increase the efficacy of conventional chemotherapy drugs with fewer side effects. The antitumor activity of many polysaccharides was significantly increased after modification. Based on these encouraging observations, a great deal of effort has been focused on discovering anti-cancer polysaccharides and modified derivatives for the development of effective therapeutics for various human cancers. This review highlights recent advances on the major chemical modification methods of polysaccharides, and discusses the effect of molecular modification on the physicochemical properties and anti-tumor activities of polysaccharides. Meanwhile, the underlying anti-tumor mechanisms of polysaccharide and its modified derivatives were also discussed.

Structural Characterization of Polysaccharides from Dendrobium officinale and Their Effects on Apoptosis of HeLa Cell Line

Dendrobium officinale is a widely used medicinal plant in China with numerous bio-activities. However, the main structure and anti-tumor activity of the polysaccharides from this plant have not been investigated. In this study, we elucidated the main structure of polysaccharides purified with DEAE and Sephadex G-25 from Dendrobium officinale grown under different planting conditions. In addition, the anti-tumor activity was tested via MTT assays. The results showed that the polysaccharides of Dendrobium officinale grown under different conditions were almost the same, with slight differences in the branched chain; both polysaccharide fractions consisted of (1→4)-linked mannose and (1→4)-linked glucose, with an O-acetyl group in the mannose. After degradation, the polysaccharide fractions from wild plants showed significant anti-proliferation activity in HeLa cells. The fractions F1 and F3 induced apoptosis by up-regulating the expression of ERK, JNK, and p38. We concluded that polysaccharides from Dendrobium officinale planted in the wild exhibit significant anti-tumor effects only after being degraded to smaller molecular weight species. The planting mode is a significant factor in the pharmacological activity of Dendrobium officinale. We advise that the planting conditions for Dendrobium officinale should be changed.

Use of Organic Wastes and Industrial By-Products to Produce Filamentous Fungi with Potential as Aqua-Feed Ingredients

Organic-rich waste and industrial by-product streams, generated in enormous amounts on a daily basis, contain substantial amounts of nutrients that are worthy of recovery. Biological conversion of organic-waste streams using filamentous fungi is a promising approach to convert nutrients into value-added bioproducts, such as fungal biomass. High-protein fungal biomass contains different kinds and levels of amino acids, fatty acids, immunostimulants, antioxidants, pigments, etc., which make it a potential choice for application in animal feed supplementation. Considering the challenges long faced by the aquaculture industry in fishmeal production due to the increasing prices and environmental concerns, the aquaculture industry is forced to provide alternative protein-rich sources to replace conventional fishmeal. In this review, the possibilities of utilization of filamentous fungi biomass cultivated on organic-rich waste streams, as an alternative nutrient source in fish feed, were thoroughly reviewed.

Sulfated Laminaria japonica polysaccharides inhibit macrophage foam cell formation

In this work, a purified Laminaria japonica polysaccharide (LJP61A) was chemically modified to obtain three sulfated polysaccharides (SLJP1, SLJP2 and SLJP3) with different degrees of sulfation using the method of chlorosulfonic acid/pyridine. The effects and underlying mechanism of SLJP1, SLJP2 and SLJP3 on the suppression of macrophage foam cell formation were further investigated using the model of oxidized low-density lipoprotein (ox-LDL)-induced foam cell formation. Results exhibited that the macrophage foam cell formation induced by ox-LDL could be significantly alleviated by these sulfated polysaccharides in a dose-dependent manner. Meanwhile, the enhancement of PPAR-γ mRNA expression in ox-LDL induced macrophages was remarkably inhibited by these sulfated polysaccharides. Moreover, the cellular inflammation induced by ox-LDL could also be remarkably mitigated by these sulfated polysaccharides. These results indicated that the sulfated L. japonica polysaccharides could inhibit the conversion of macrophage into foam cell via obstructing PPAR-γ activation and alleviating cellular inflammation.

Dendrobium officinale Orchid Extract Prevents Ovariectomy-Induced Osteoporosis in Vivo and Inhibits RANKL-Induced Osteoclast Differentiation in Vitro

Background:Dendrobium officinale, a traditional Chinese medical herb with high value that is widely used in Asia, possesses many positive effects on human health, including anti-chronic inflammation, anti-obesity, and immune modulation properties; however, whether D. officinale has inhibitory effects on postmenopausal osteoporosis remains unknown. Objective: We investigated the effects of D. officinale extract (DOE) on ovariectomy-induced bone loss in vivo and on osteoclastogenesis in vitro. Methods:In vivo, female rats were divided into a sham-operated (sham) group and five ovariectomized (OVX) subgroups: OVX with vehicle (OVX), OVX with Xian-Ling-Gu-Bao capsule (240 mg/kg body weight/day), and OVX with low-, medium-, and high-dose DOE (150, 300, and 600 mg/kg body weight/day, respectively). Animals in each group were administered their corresponding treatments for 13 weeks. Body weight, serum biochemical parameters, uterine and femoral physical parameters, bone mineral density (BMD), bone biomechanical properties, and bone microarchitecture were obtained. In vitro, the effects of DOE on osteoclastogenesis were examined using RAW264.7 cells. The effects of DOE on osteoclastogenesis and the expression of osteoclast-specific marker genes and proteins were determined. Results: DOE effectively ameliorated serum biochemical parameters, especially alleviated estradiol (E2) deficiency and maintained calcium and phosphorus homeostasis. DOE improved uterine and femoral physical parameters. In addition, DOE improved femoral BMD and biomechanical properties. DOE significantly ameliorated bone microarchitecture. Moreover, DOE inhibited osteoclastogenesis independent of its cytoxicity and suppressed the expression of osteoclast-specific marker genes and proteins. Conclusion: DOE can effectively prevent ovariectomy-induced bone loss in vivo and inhibit osteoclastogenesis in vitro.

Advances on Bioactive Polysaccharides from Medicinal Plants

In recent decades, the polysaccharides from the medicinal plants have attracted a lot of attention due to their significant bioactivities, such as anti-tumor activity, antioxidant activity, anticoagulant activity, antidiabetic activity, radioprotection effect, anti-viral activity, hypolipidemic and immunomodulatory activities, which make them suitable for medicinal applications. Previous studies have also shown that medicinal plant polysaccharides are non-toxic and show no side effects. Based on these encouraging observations, most researches have been focusing on the isolation and identification of polysaccharides, as well as their bioactivities. A large number of bioactive polysaccharides with different structural features and biological effects from medicinal plants have been purified and characterized. This review provides a comprehensive summary of the most recent developments in physiochemical, structural features and biological activities of bioactive polysaccharides from a number of important medicinal plants, such as polysaccharides from Astragalus membranaceus, Dendrobium plants, Bupleurum, Cactus fruits, Acanthopanax senticosus, Angelica sinensis (Oliv.) Diels, Aloe barbadensis Miller, and Dimocarpus longan Lour. Moreover, the paper has also been focused on the applications of bioactive polysaccharides for medicinal applications. Recent studies have provided evidence that polysaccharides from medicinal plants can play a vital role in bioactivities. The contents and data will serve as a useful reference material for further investigation, production, and application of these polysaccharides in functional foods and therapeutic agents.

Purification, characterization and immunoregulatory activity of a polysaccharide isolated from Hibiscus sabdariffa L

BACKGROUND

Hibiscus sabdariffa L. is not only used traditionally as a component of herbal drinks, beverages and flavoring agents but also as a herbal medicine in the drug industry. Bioactive polysaccharides are important constituents of H. sabdariffa that may contribute to the plant's beneficial effects. This study was designed to investigate the structural characteristics of a water-soluble polysaccharide from H. sabdariffa, HSP41, and its immunoregulatory activity on RAW264.7 cells.

RESULTS

HSP41 was mainly composed of arabinose, xylose and mannose at a molar ratio of 1:1.34:15.6, with an average molecular weight of 3.3 × 10⁵  Da. Fourier transform infrared (FTIR) spectra exhibited absorption peaks characteristic of HSP41. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed the amorphous form and aggregation conformation of HSP41 respectively. HSP41 significantly induced interleukin 1β (IL-1β) and inducible nitric oxide synthase (iNOS) expression in RAW264.7 cells in vitro, promoting an increase in nuclear factor kB p65 (NF-kB p65) levels in the nucleus.

CONCLUSION

The results indicated that HSP41 up-regulated the immune response by stimulating RAW264.7 cell activity. HSP41, a promising immunoregulator, possibly contributes to the health benefits of H. sabdariffa and might have potential applications in health food or medicine. © 2016 Society of Chemical Industry.

Qualitative and quantitative analysis of specific polysaccharides in Dendrobium huoshanense by using saccharide mapping and chromatographic methods

Qualitative and quantitative analysis of specific polysaccharides from ten batches of Dendrobium huoshanense were performed using high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) and saccharide mapping based on polysaccharides analysis by using carbohydrate gel electrophoresis (PACE) and high performance thin layer chromatography (HPTLC). Results showed that molecular weights, the radius of gyrations, and contents of specific polysaccharides in D. huoshanense were ranging from 1.16×10(5) to 2.17×10(5)Da, 38.8 to 52.1nm, and 9.9% to 19.9%, respectively. Furthermore, the main monosaccharide compositions were Man and Glc. Indeed, the main glycosidic linkages were β-1,4-Manp and β-1,4-Glcp, and substituted with acetyl groups at O-2 and O-3 of 1,4-linked Manp. Moreover, results showed that PACE and HPTLC fingerprints of partial acidic and enzymatic hydrolysates of specific polysaccharides were similar, which are helpful to better understand the specific polysaccharides in D. huoshanense and beneficial to improve their quality control. These approaches could also be routinely used for quality control of polysaccharides in other medicinal plants.

Toll-like receptor 4-related immunostimulatory polysaccharides: Primary structure, activity relationships, and possible interaction models

Toll-like receptor (TLR) 4 is an important polysaccharide receptor; however, the relationships between the structures and biological activities of TLR4 and polysaccharides remain unknown. Many recent findings have revealed the primary structure of TLR4/MD-2-related polysaccharides, and several three-dimensional structure models of polysaccharide-binding proteins have been reported; and these models provide insights into the mechanisms through which polysaccharides interact with TLR4. In this review, we first discuss the origins of polysaccharides related to TLR4, including polysaccharides from higher plants, fungi, bacteria, algae, and animals. We then briefly describe the glucosidic bond types of TLR4-related heteroglycans and homoglycans and describe the typical molecular weights of TLR4-related polysaccharides. The primary structures and activity relationships of polysaccharides with TLR4/MD-2 are also discussed. Finally, based on the existing interaction models of LPS with TLR4/MD-2 and linear polysaccharides with proteins, we provide insights into the possible interaction models of polysaccharide ligands with TLR4/MD-2. To our knowledge, this review is the first to summarize the primary structures and activity relationships of TLR4-related polysaccharides and the possible mechanisms of interaction for TLR4 and TLR4-related polysaccharides.

Preclinical Models for Investigation of Herbal Medicines in Liver Diseases: Update and Perspective

Liver disease results from a dynamic pathological process associated with cellular and genetic alterations, which may progress stepwise to liver dysfunction. Commonly, liver disease begins with hepatocyte injury, followed by persistent episodes of cellular regeneration, inflammation, and hepatocyte death that may ultimately lead to nonreversible liver failure. For centuries, herbal remedies have been used for a variety of liver diseases and recent studies have identified the active compounds that may interact with liver disease-associated targets. Further study on the herbal remedies may lead to the formulation of next generation medicines with hepatoprotective, antifibrotic, and anticancer properties. Still, the pharmacological actions of vast majority of herbal remedies remain unknown; thus, extensive preclinical studies are important. In this review, we summarize progress made over the last five years of the most commonly used preclinical models of liver diseases that are used to screen for curative herbal medicines for nonalcoholic fatty liver disease, liver fibrosis/cirrhosis, and liver. We also summarize the proposed mechanisms associated with the observed liver-protective, antifibrotic, and anticancer actions of several promising herbal medicines and discuss the challenges faced in this research field.

Structural characterization and immunomodulating activity of polysaccharide from Dendrobium officinale

A neutral heteropolysaccharide (DOP-1-1) consisted by mannose and glucose (5.9:1) with an average molecular weight at about 1.78×10(5) Da was purified from Dendrobium officinale. Based on Fourier transform infrared spectrum (FT-IR) and nuclear magnetic resonance (NMR) spectra, it suggested that partial structure of DOP-1-1 is an O-acetylated glucomannan with β-d configuration in pyranose sugar forms. The immunomodulatory activity of DOP-1-1 was evaluated by secretion level of cytokine (interleukin (IL)-1β and IL-10) and tumor necrosis factor (TNF)-α in vitro. Our results suggested that DOP-1-1 could stimulate cytokine production (TNF-α, IL-1β) in cells. These findings demonstrated that the purified polysaccharide from D. officinale presented significant immune-modulating activities. Furthermore, by Western-blot we can found that the signaling pathways of DOP-1-1 induced immune activities involving ERK1/2 and NF-кB. As to antioxidant activity, DOP-1-1 hadn't showed remarkable scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in contrast with other studies of polysaccharides from D. officinale.

Symbiotic in vitro seed propagation of Dendrobium: fungal and bacterial partners and their influence on plant growth and development

The genus Dendrobium is one of the largest genera of the Orchidaceae Juss. family, although some of its members are the most threatened today. The reason why many species face a vulnerable or endangered status is primarily because of anthropogenic interference in natural habitats and commercial overexploitation. The development and application of modern techniques and strategies directed towards in vitro propagation of orchids not only increases their number but also provides a viable means to conserve plants in an artificial environment, both in vitro and ex vitro, thus providing material for reintroduction. Dendrobium seed germination and propagation are challenging processes in vivo and in vitro, especially when the extreme specialization of these plants is considered: (1) their biotic relationships with pollinators and mycorrhizae; (2) adaptation to epiphytic or lithophytic life-styles; (3) fine-scale requirements for an optimal combination of nutrients, light, temperature, and pH. This review also aims to summarize the available data on symbiotic in vitro Dendrobium seed germination. The influence of abiotic factors as well as composition and amounts of different exogenous nutrient substances is examined. With a view to better understanding how to optimize and control in vitro symbiotic associations, a part of the review describes the strong biotic relations of Dendrobium with different associative microorganisms that form microbial communities with adult plants, and also influence symbiotic seed germination. The beneficial role of plant growth-promoting bacteria is also discussed.

Evaluation of chemical constituents and important mechanism of pharmacological biology in dendrobium plants

Dendrobium species, commonly known as “Shihu” or “Huangcao,” represents the second largest genus of Orchidaceae, which are used commonly as tonic herbs and healthy food in many Asian countries. The aim of this paper is to review the history, chemistry, and pharmacology of different Dendrobium species on the basis of the latest academic literatures found in Google Scholar, PubMed, Sciencedirect, Scopus, and SID.