Structure and anti-tumor activity of a polysaccharide from Bletilla ochracea Schltr

Plant mucus-derived microgels: Blood-triggered gelation and strong hemostatic adhesion

Arrest of bleeding usually applies clotting agents to trigger coagulation procedures or adhesives to interrupt blood flow through sealing the vessel; however, the efficiency is compromised. Here, we propose a concept of integration of hemostasis and adhesion via yam mucus's microgels. The mucus microgels exhibit attractive attributes of hydrogel with uniform size and shape. Their shear-thinning, self-healing and strong adhesion make them feasible as injectable bioadhesion. Exceptionally, the blood can trigger the microgels' gelation with the outcome of super extensibility, which leads to the microgels a strong hemostatic agent. We also found a tight gel adhesive layer formed upon microgels' contacting the blood on the tissue, where there is the coagulation factor XIII triggered to form a dense three-dimensional fibrin meshwork. The generated structures show that the microgels look like hard balls in the dispersed phase into the blood-produced fibrin mesh of a soft net phase. Both phases work together for a super-extension gel. We demonstrated the microgels' fast adhesion and hemostasis in the livers and hearts of rabbits and mini pigs. The microgels also promoted wound healing with good biocompatibility and biodegradability.

Research progress in the preparation, structural characterization, and biological activities of polysaccharides from traditional Chinese medicine

Traditional Chinese medicines are tremendous sources of polysaccharides, which are of great interest in the human welfare system as natural medicines, food, and cosmetics. This review aims to highlight the recent trends in extraction (conventional and non-conventional), purification and analytic techniques of traditional Chinese medicine polysaccharides (TCMPs), and the chemical structure, biological activities (anti-tumor, hypoglycemic, antioxidant, intestinal flora regulation, immunomodulatory, anti-inflammatory, anti-aging, hypolipidemic, hepatoprotective, and other activities), and the underlying mechanisms of polysaccharides extracted from 76 diverse traditional Chinese medicines were compared and discussed. With this wide coverage, a total of 164 scientific articles were searched from the database including Google Scholar, PubMed, Web of Science, and China Knowledge Network. This comprehensive survey from previous reports indicates that TCMPs are non-toxic, highly biocompatible, and good biodegradability. Besides, this review highlights that TCMPs may be excellent functional factors and effective therapeutic drugs. Finally, the current problems and future research advances of TCMPs are also introduced. New valuable insights for the future researches regarding TCMPs are also proposed in the fields of therapeutic agents and functional foods.

Skin healthcare protection with antioxidant and anti-melanogenesis activity of polysaccharide purification from Bletilla striata

In this study, we investigated the structural characterization and biological activities of Bletilla striata polysaccharides (BSPs) for their role as antioxidants and anti-melanogenesis agents in skin healthcare protection. Three neutral polysaccharides (BSP-1, BSP-2, and BSP-3) with molecular weights of 269.121 kDa, 57.389 kDa, and 28.153 kDa were extracted and purified. Their structural characteristics were analyzed by ion chromatography, GC-MS, and 1D/2D NMR. The results showed that BSP-1, which constitutes the major part of BSPs, was composed of α-D-Glcp, β-D-Glcp, β-D-Manp, and 2-O-acetyl-β-D-Manp, with the branched-chain accompanied by β-D-Galp and α-D-Glcp. BSP-1, BSP-2, and BSP-3 can enhance the total antioxidant capacity of skin fibroblasts with non-toxicity. Meanwhile, BSP-1, BSP-2, and BSP-3 could significantly inhibit the proliferative activity of melanoma cells. Among them, BSP-1 and BSP-2 showed more significance in anti-melanogenesis, tyrosinase inhibition activity, and cell migration inhibition. BSPs have effective antioxidant capacity and anti-melanogenesis effects, which should be further emphasized and developed as skin protection components.

Structural analysis of a soluble polysaccharide GSPA-0.3 from the root of Panax ginseng C. A. Meyer and its adjuvant activity with mechanism investigation

A novel polysaccharide (GSPA-0.3) was isolated and purified from the root of cultivated Panax ginseng C. A. Meyer, and its structure, adjuvant activities, and mechanisms for inducing the maturation of mouse dendritic 2.4 cells (DC2.4) were extensively studied. Fraction GSPA-0.3, mainly composed by the galacturonic acid, galactose, arabinose, glucose, rhamnose, mannose, and xylose, had a molecular weight of 62,722 Da. The main chain of GSPA-0.3 was composed of →3)-α-L-Rhap-(1→, →4)-α-D-GalpA-(1→, and →3, 4)-α-D-GalpA-(1→. Branched chains comprised α-L-Araf-(1→3, 5)-α-L-Araf-(1→5)-α-L-Araf-(1→, α-D-Glcp-(1→6)-α-D-Glcp-(1→6)-α-D-Glcp-(1→, β-D-Galp-(1→4)-β-D-Galp-(1→4)-β-D-Galp-(1→, and α-D-GalpA-(1→ units connected to the C3 position of →3, 4)-α-D-GalpA-(1→. In vivo, GSPA-0.3 was found to stimulate the production of IgG, IgG1, and IgG2a; increase the splenocyte proliferation index; and promote the expression of GATA-3, T-bet, IFN-γ, and IL-4 in H1N1 vaccine-immunized mice. Moreover, GSPA-0.3 significantly increased the levels of neutralizing antibodies in the mice, and its adjuvant activity was found to be superior to aluminum adjuvant (Alum adjuvant). Mechanistic investigations showed that GSPA-0.3 activated the TLR4-dependent pathway by upregulating the expressions of TLR4, MyD88, TRAF-6, and NF-κB proteins and gens. The results presented herein suggested that GSPA-0.3 could significantly promote the efficacy of the H1N1 vaccine by modulating Th1/Th2 response via the TLR4-MyD88-NF-κB signaling pathway.

A polysaccharide from Inula japonica showing in vivo antitumor activity by interacting with TLR-4, PD-1, and VEGF

Polysaccharides, an important class of carbohydrate polymers, are considered as one of the sources of drug molecules. To discover bioactive polysaccharides as potential agents against cancer, a homogeneous polysaccharide (IJP70-1) has been purified from the flowers of Inula japonica, which is a traditional medicinal plant used for various medical indications. IJP70-1 with a molecular weight of 1.019 × 105 Da was mainly composed of →5)-α-l-Araf-(1→, →2,5)-α-l-Araf-(1→, →3,5)-α-l-Araf-(1→, →2,3,5)-α-l-Araf-(1→, →6)-α-d-Glcp-(1→, →3,6)-α-d-Galp-(1→, and t-α-l-Araf. Apart from the characteristics and structure elucidated by various techniques, the in vivo antitumor activity of IJP70-1 was assayed using zebrafish models. In the subsequent mechanism investigation, it was found that the in vivo antitumor activity of IJP70-1 was not cytotoxic mechanism caused, but related to the activation of the immune system and inhibition of angiogenesis by interacting with the proteins toll-like receptor-4 (TLR-4), programmed death receptor-1 (PD-1), and vascular endothelial growth factor (VEGF). The chemical and biological studies have shown that the homogeneous polysaccharide IJP70-1 has the potential to be developed into an anticancer agent.

Colorectal cancer inhibitory properties of polysaccharides and their molecular mechanisms: A review

Colorectal cancer (CRC) is one of the three major malignant tumors in the world. The major treatments currently recommended for it are surgery, radiotherapy, and chemotherapy, all of which are frequently accompanied by a poor prognosis and high recurrence rate. To limit cell proliferation and metastasis, trigger cell apoptosis, and regulate tumor microenvironment (TME), researchers are focusing attention on investigating highly effective and non-toxic natural medicines. According to the research reported in 89 pieces of related literature, between 2018 and 2021, specialists extracted 48 different types of polysaccharides with CRC inhibitory actions from various plants, including Dendrobium officinale Kimura et Migo., Nostoc commune Vaucher, and Ganoderma lucidum (Leyss. ex Fr.) Karst. The novel founded mechanisms mainly include: inhibiting cancer cell proliferation by acting on IRS1/PI3K/Akt and IL-6/STAT3 pathways; inducing cancer cell apoptosis by acting on LncRNA HOTAIR/Akt mediated-intrinsic apoptosis, or regulating the TNF-α-mediated extrinsic apoptosis; inducing cancer cell autophagy by acting on endoplasmic reticulum stress or mTOR-TFEB pathway; inhibiting cancer cell metastasis by regulating Smad2/3 and TLR4/JNK pathways; regulating TME in CRC; and maintaining the intestinal barrier. This review will provide more novel research strategies and a solid literature basis for the application of polysaccharides in the treatment of CRC.

Structural characterization of corn fiber hemicelluloses extracted by organic solvent and screening of degradation enzymes

An integrated treatment coupling peracetic acid delignification, dimethyl sulfoxide extraction, and ethanol precipitation were performed to isolate hemicellulose from de-starched corn fiber. Based on chemical composition, molecular weight distribution, methylation, and nuclear magnetic resonance spectroscopy, it is proposed that hemicelluloses in corn fiber were composed of two polysaccharides, glucuronoarabinoxylan (about 80 %) and xyloglucan (about 20 %). Xylose (about 46 %) and arabinose (about 32 %) were the main components in glucuronoarabinoxylan. More than half of the xylose units in the glucuronoarabinoxylan backbone chain were substituted at O-2 and/or O-3 by various monomers or oligomeric side chains. Based on structure analysis, five hemicellulases were selected and added to Penicillium oxalicum MCAX enzymes for enzymatic hydrolysis of corn fiber. The results showed that the addition of hemicellulases increased the sugar yield of corn fiber. These results demonstrate the effectiveness of enzyme consortium constructed by elucidating the chemical structure of hemicellulose in corn fiber for the degradation of corn fiber and also provide a general solution for the rational construction of targeted and efficient enzyme systems for the degradation of lignocellulosic biomass.

Polysaccharides from Chinese materia medica: Perspective towards cancer management

Cancer has always been a focus of global attention, and the difficulty of treatment and poor prognosis have always plagued humanity. Conventional chemotherapeutics and treatment with synthetic disciplines will cause adverse side effects and drug resistance. Therefore, searching for a safe, valid, and clinically effective drug is necessary. At present, some natural compounds have proved to have the potential to fight cancer. Polysaccharides obtained from Chinese materia medica are good anti-cancer ingredients. Polysaccharides are macromolecular compounds of equal or distinct monosaccharides with an α- or β-glycosidic bonds. The anti-cancer activity has been fully demonstrated in vivo and in vitro. However, Chinese materia medica polysaccharides are only used as adjuvant therapy for cancer-related diseases. Hence, this review mainly discusses the chemical composition, biological activity, absorption in vivo, and clinical application of Chinese materia medica polysaccharides. Also, we discussed the anti-cancer mechanism. We also discussed the current research's limitations on treating cancer with Chinese materia medica polysaccharides and insights into future research.

A water-soluble polysaccharide from Eucommia folium: the structural characterization and anti-tumor activity in vivo

In this study, a water-soluble polysaccharide from Eucommia folium was extracted by hot water and purified using Sephadex G-200 gel columns. The results showed that the purified fraction (EFP) has a molecular weight of 9.98 × 10⁵ Da and consisted of rhamnose, arabinose, galactose, glucose, mannose, xylose, galacturonic acid, and glucuronic acid (molar ratio: 0.226: 1.739: 2.183: 1: 0.155: 0.321: 0.358: 0.047). The combination of infrared spectroscopy and NMR analysis proved that EFP is an acidic polysaccharide whose main chain consists of α-L-Araf-(1 → , → 3,5)-α-Araf-(1 → , → 3)-β-Galp-(1 → , → 3,6)-β-Glcp-(1 → , → 2)-α-D-Manp-(1 → , → 4)-α-GalpA-(1 → , → 2,4)-α-Rhap-(1 → . In addition, the in vivo antitumoral activity of EFP was studied using a H22 tumor-bearing mice model. EFP effectively inhibited tumor growth in mice following intragastric administration. By Combining with the results of the apoptosis assay and JC-1 staining analysis, we confirmed that EFP induces apoptosis through the mitochondrial pathway. Furthermore, cell cycle analysis demonstrated that EFP blocks the cell cycle at S phase.

Cyanidin Alleviated CCl4-Induced Acute Liver Injury by Regulating the Nrf2 and NF-κB Signaling Pathways

Acute liver injury has multiple causes and can result in liver failure. In this study, we evaluated the hepatoprotective ability of cyanidin (Cy) and investigated its associated mechanisms. Cy administration significantly and dose-dependently ameliorated acute liver injury induced by carbon tetrachloride (CCl₄). High-dose Cy showed effects comparable to those achieved by the positive control (silymarin). Severe oxidative stress and inflammatory responses in the liver tissue induced by CCl₄ were significantly mitigated by Cy supplementation. The total antioxidant capacity and the activity of superoxide dismutase, catalase, and glutathione peroxidase were increased and the content of malondialdehyde, lipid peroxide, tumor necrosis factor α, interleukin-1β, and interleukin-6 were decreased. Additionally, the Nrf2 and NF-κB signaling pathways, which regulate antioxidative and inflammatory responses, were analyzed using quantitative real-time polymerase chain reaction and western blot assay. Cy treatment not only increased Nrf2 transcription and expression but also decreased NF-κB signaling. Moreover, molecular docking simulation indicated that Cy had high affinity for Keap1 and NF-κB/p65, which may promote nuclear translocation of Nrf2 and inhibit that of NF-κB. In summary, Cy treatment exerted antioxidative and anti-inflammatory effects and ameliorated liver injury by increasing Nrf2 and inhibiting the NF-κB pathway, demonstrating the potential of Cy as a therapeutic agent in liver injury.

Acetylated polysaccharides: Synthesis, physicochemical properties, bioactivities, and food applications

Polysaccharides are biomacromolecular widely applied in the food industry, as gelling agents, thickeners and health supplements. As hydrophobic groups, acetyls provide amphiphilicity to polysaccharides with numerous hydroxyl groups, which greatly expand the presence of polysaccharides in organic organisms and various chemical environments. Acetylation could result in diverseness and promotion of the structure of polysaccharides, which improve the physicochemical properties and biological activities. High efficient and environmentally friendly access to acetylated derivatives of different polysaccharides is being explored. This review discusses and summarizes acetylated polysaccharides in terms of synthetic methods, physicochemical properties and biological activities and emphasizes the structure-effect relationships introduced by acetyl groups to reveal the potential mechanism of acetylated polysaccharides. Acetyls with different contents and substitution sites could change the molecular weight, monosaccharide composition and spatial architecture of polysaccharides, resulting in differences among properties such as water solubility, emulsification and crystallinity. Coupled with acetyls, polysaccharides have increased antioxidant, immunomodulatory, antitumor, and pro-prebiotic capacities. In addition, their possible applications have also been discussed in green food materials, bioactive ingredient carriers and functional food products, indicating that acetylated polysaccharides hold a clear vision in food health and industrial development.

A novel acidic polysaccharide from blackened jujube: Structural features and antitumor activity in vitro

Liver cancer is one of the most common cancers, with increasing trends in incidence and mortality. A novel acidic polysaccharide (BJP-2) obtained from blackened jujube was extracted by hot water followed by chromatographic purification employing DEAE-cellulose 52 and Sephadex G-100 column. And then BJP-2 was identified by SEC-MALLS-RI, GC-MS, methylation and NMR for the following characteristics: molecular weight of 6.42 × 104 Da, monosaccharide composition of glucuronic acid (GalA), arabinose (Ara), galactose (Gal), rhamnose (Rha), xylose (Xyl), glucuronic acid (GlcA), glucose (Glc), fucose (Fuc) and mannose (Man) with the percentage of 39.78, 31.93, 16.86, 6.43, 1.86, 1.28, 1.02, 0.61, and 0.23%, as well as the main chain of → 5)-α-L-Araf (1 → 4)-β-D-Gal(1 → , T-α-L-Araf (1 → 4)-β-D-Gal(1 → , and → 4)-α-L-6MeGalAp(1 → . The effect of BJP-2 on the apoptosis of HepG2 cells and its anti-tumor mechanism were further explored. The analysis by MTT and flow cytometry showed that BJP-2 suppressed cell proliferation by inducing apoptosis in a concentration-dependent manner. Cell scratching and Transwell revealed that BJP-2 was able to block the invasion and metastasis of tumor cells. Western blot results demonstrated that BJP-2 exhibited antitumor activity through a mitochondria-dependent pathway, as evidenced by overexpression of Bax, Cleaved Caspase-3/Caspase-3 and Cleaved Caspase-9/Caspase-9 and downregulation of Bcl-2. Therefore, BJP-2 has broad research prospects as a tumor preventive or therapeutic agent.

The structures of two glucomannans from Bletilla formosana and their protective effect on inflammation via inhibiting NF-κB pathway

Bletilla formosana is a traditional Chinese herbal medicine and is widely consumed as foods and medicines in China. However, the chemical structure and bioactivity of its polysaccharides remain unknown. Herein, two new polysaccharides, BFP60 and BFP80, with molecular weights of 3.99 kDa and 10.07 kDa, respectively, were isolated and purified from dried tuber of B. formosana. Structural analysis suggested that BFP60 and BFP80 may have backbone consisted of →4)-β-d-Man-(1→,→4)-β-d-Glc-(1→,→4)-2-O-acetyl-β-d-Man-(1→, and →4)-3-O-acetyl-β-d-Man-(1→. Inflammation assay in LPS-induced RAW264.7 cells showed that the productions of NO and pro-inflammatory cytokines including IL-6, IL-1β, TNF-α, and IFN-γ were significantly reduced, and the expression of iNOS, COX-2, and target proteins in the NF-κB pathway were suppressed after BFP60 and BFP80 pretreatment. These findings indicated that this novel polysaccharide had significant inflammatory protective effects in vitro.

Effects of Sparassis latifolia neutral polysaccharide on immune activity via TLR4-mediated MyD88-dependent and independent signaling pathways in RAW264.7 macrophages

Background

Sparassis latifolia (S. latifolia) is a precious edible fungus with multiple biological activities. To date, no study has been investigated the underlying molecular mechanism of immunoregulation caused by the neutral polysaccharide of S. latifolia.

Materials and methods

To investigate immunomodulatory mechanism of S. latifolia neutral polysaccharide (SLNP), SLNP was obtained from S. latifolia and its structure, immune receptors and regulation mechanism were studied.

Results

S. latifolia neutral polysaccharide consisted of arabinose, galactose, glucose, xylose, and mannose with a molar ratio of 6:12:63:10:5. SLNP was a pyran polysaccharide with a relative molecular weight of 3.2 × 105 Da. SLNP promoted the proliferation of RAW264.7, which further induced the secretions of nitric oxide, TNF-α, IL-6, and IFN-β, and upregulated the immune receptor TLR4 expression. Moreover, SLNP increased remarkably the levels of TRAF6, IRF3, JNK, ERK, p38, and p38 mRNA and protein mediated by TLR4.

Conclusion

S. latifolia neutral polysaccharide regulated the immune function of RAW264.7 through MyD88-dependent and -independent signaling pathways mediated by TLR4 receptor, which suggests that SLNP is a new immunomodulator.

Stropharia rugoso-annulata acetylated polysaccharides alleviate NAFLD via Nrf2/JNK1/AMPK signaling pathways

The acetylated Stropharia rugoso-annulata polysaccharides (ASRP) was successfully characterized, and the effects and mechanism on alleviating NAFLD were investigated in HFD-induced mice models. The characterization showed that ASRP was successfully acetylated and rich in galactose. The animal studies demonstrated that ASRP at the dose of 400 mg/kg possessed hepatoprotective effects by potential antioxidation, anti-inflammation and improving hepatocellular histopathology, with the possible mechanisms on regulating the JNK1/AP-1 and activating the Nrf2 signaling pathways. Besides, ASRP could improve the fat metabolism by activating the AMPK/SREBP-1c signaling pathways. The results provided basal theories for the development of ASRP on treating the NAFLD and its complications.

Current Advancements in Antitumor Properties and Mechanisms of Medicinal Components in Edible Mushrooms

Edible and medicinal fungi, a group of eukaryotic organisms with numerous varieties, including Coriolus versicolor, Ganoderma lucidum, Cordyceps sinensis, Pleurotus ostreatus, and Grifola frondosa, have been demonstrated to possess a board range of pharmaceutical properties, including anti-virus, anti-inflammation, and neuroprotection. Moreover, edible and medicinal fungi have been traditionally consumed as food to provide multiple nutrients and as drugs owing to having the activities of invigorating blood circulation, reinforcing the healthy qi, clearing away heat, and eliminating stasis for thousands of years in China. Malignant tumors, well-known as the second leading cause of death globally, accounted for nearly 10 million deaths in 2020. Thus, in-depth exploration of strategies to prevent and treat cancer is extremely urgent. A variety of studies have reported that the main bioactive components of edible and medicinal fungi, mainly polysaccharides and triterpenoids, exhibit diverse anticancer activities via multiple mechanisms, including inhibition of cell proliferation and metastasis, induction of apoptosis and autophagy, reversing multidrug resistance, and regulation of immune responses, thus suggesting their substantial potential in the prevention and treatment of cancer. Our review summarizes the research progress on the anticancer properties of edible and medicinal fungi and the underlying molecular mechanism, which may offer a better understanding of this field. Additionally, few studies have reported the safety and efficacy of extracts from edible and medicinal fungi, which may limit their clinical application. In summary, there is a need to continue to explore the use of those extracts and to further validate their safety and efficacy.

Structural characterization of a polysaccharide from Trametes sanguinea Lloyd with immune-enhancing activity via activation of TLR4

A bioactive polysaccharide (TS2-2A) with a molecular weight of 15 kDa was isolated from Trametes sanguinea Lloyd, a medicinal food homologous fungus, by water extraction-alcohol precipitation and chromatographic separation. NMR analysis of polysaccharide and MS/MS analysis of its oligosaccharide indicated that TS2-2A featured a novel straight chain with a backbone of 1,3-α-d-glucopyranose and 1,4-β-d-glucopyranose at a molar ratio of 1:4. Moreover, TS2-2A, recognized by Toll-like receptor 4 (TLR4), stimulated RAW 264.7 macrophages to release related cytokines and contributed to immune-enhancing effects. Briefly, with remarkable immune-enhancing activity and noncytotoxicity, TS2-2A was proposed to be a potential immune enhancer for supplementing drugs or functional foods.

Screening of Bletilla striata, Bletilla ochracea, and Oreorchis foliosa differential metabolites based on metabolomics

As a representative medicinal plant in Orchidaceae, Bletilla striata plays a variety of pharmacological roles in the clinic. However, the emergence of counterfeit species affects the basic medicinal materials source identification process, of which Bletilla ochracea and Oreorchis foliosa of Orchidaceae are two representative species. For this study, 13 representative B. striata samples, 3 B. ochracea samples and 3 O. foliosa samples were selected for the systematic determination of polysaccharide yields and monosaccharide composition, and further detection of secondary metabolites by HPLC-MS. The results revealed that there was a significant difference in the yields of polysaccharides between B. striata and B. ochracea (P = 0.006). Although the polysaccharides of both species were composed of glucose and mannose, the molar ratio of the two monosaccharides was different suggested that the structures of the polysaccharide were different. The metabolomics results showed that there were no differences in the types of metabolites between B. striata and B. ochracea; however, there were differences in the content of these metabolites. Although there was no significant difference in the polysaccharide yields of B. striata and O. foliosa (P = 0.074) and the monosaccharide composition was the same (glucose and mannose), many different metabolites were screened out between them: 6 compounds such as C₃₆ H₃₄ O₁₁ existed only in B. striata, while substance C₃₉ H₅₄ O₂₂ was unique to O. foliosa. Therefore, based on the analysis of the polysaccharide content and monosaccharide composition, combined with phase metabolomics research, a preliminary distinction between B. striata, B. ochracea, and O. foliosa was achieved.

Structural characterisation and bioactivity of polysaccharides isolated from fermented Dendrobium officinale

BACKGROUND

A polysaccharide was purified in this study, which was acquired from the fermentation broth of Dendrobium officinale Kimura et Migo. We aimed to investigate the structural features and bioactivity of this polysaccharide.

RESULTS

The polysaccharide was purified and the main polysaccharide fraction (i.e., DOP-1) was obtained. High-performance gel permeation chromatography (HPGPC) revealed that the molecular weight of DOP-1 was 447.48 kDa. Galactose, glucose and mannose were found to be present in DOP-1 via monosaccharide composition analysis, at a ratio of 1:1.79:6.71. Methylation and nuclear magnetic resonance spectroscopic analysis indicated that the backbone of DOP-1 was →4)-α-d-Glcp-(1 → 4)-α-d-Manp-(1 → 4)-α-d-Manp-(1 → 4,6)-α-d-Manp-(1→, and its repeating units were also preliminarily established. In vitro tests proved that DOP-1 not only protects RAW264.7 macrophages from the cytotoxic effect induced by lipopolysaccharide (LPS), but also inhibits cytokines (i.e., interleukin-6 and tumour necrosis factor-α) induced by LPS. DOP-1 demonstrated good scavenging activity in vitro toward 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals, as well as good metal chelating activity. Therefore, DOP-1 has potential antioxidant applications.

CONCLUSION

The structural characteristics of DOP-1 support its favourable biological activities and lay a strong foundation for further exploration of its structure-activity relationships and activity development, providing experimental data for the development and utilisation of fermentation broth of D. officinale. © 2021 Society of Chemical Industry.

The medicinal uses of the genus Bletilla in traditional Chinese medicine: A phytochemical and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Different orchids are important in traditional medicine, and species belonging to the genus Bletilla are important. Bletilla species have been used for thousands of years in Traditional Chinese Medicine (TCM) for the treatment of several health disorders, such as gastrointestinal disorders, peptic ulcer, lung disorders, and traumatic bleeding etc. AIM OF THIS REVIEW: This review aims to provide a systematic overview and objective analysis of Bletilla species and to find the probable relationship between their traditional use, chemical constituents, and pharmacological activities, while assessing their therapeutic potential in treatment of different human diseases.

MATERIALS AND METHODS

Relevant literatures on Bletilla species have been collected using the keywords "Bletilla", "phytochemistry", and "pharmacology" in scientific databases, such as "PubMed", "Scifinder", "The Plant List", "Elsevier", "China Knowledge Resource Integrated databases (CNKI)", "Google Scholar", "Baidu Scholar", and other literature sources, etc. RESULTS: This review indicates the isolation and identification of over 261 compounds from this genus, till December 2020. These chemical isolates belong to the stilbenes (bibenzyls and phenanthrenes), flavonoids, triterpenoids, steroids, simple phenolics, and glucosyloxybenzyl 2-isobutylmalates classes of compounds. These compounds have been reported to be characteristically distributed in Bletilla striata (Thunb.) Rchb. f. (BS), Bletilla ochracea Schltr. (BO), and Bletilla formosana (Hayata) Schltr. (BF). The crude extracts and pure compounds derived from the three Bletilla species have reportedly exhibited a wide spectrum of in vitro and in vivo pharmacological effects, such as hemostatic, anti-inflammatory, anti-tumor, and anti-microbial activities. As a Traditional Chinese Medicine (TCM), Bletilla species or preparations containing Bletilla species have been used for the treatment of epistaxis, gastrointestinal bleeding, cough and hemoptysis, gastric and duodenal ulcer, and traumatic injuries. Thus, Bletilla species have proven potential both in traditional uses and scientific studies.

CONCLUSIONS

Pharmacological studies have validated the use of Bletilla species in the traditional medicine, especially hemorrhagic diseases. Polysaccharides and stilbenes are the major bioactive chemical constituents of Bletilla genus according to the literatures. However, the mechanism of action of these molecules is yet to be studied. In addition, a detailed comparative analysis of the phytochemistry and biological activities of the three Bletilla species (BS, BO and BF) is highly recommended for understanding their ethnopharmacological uses and applications in clinics. Clinical toxicity tests on BS have been found to be negative, but it can't be used with Aconitum carmichaeli in traditional uses. Furthermore, not many reports are present in the literature regarding the conservation of Bletilla species.

Effects of Lactobacillus plantarum Fermentation on the Chemical Structure and Antioxidant Activity of Polysaccharides from Bulbs of Lanzhou Lily

Recently, Lanzhou lily has attracted more attention because of its bioactive components specifically polysaccharides. We studied in vitro the effects of Lactobacillus plantarum fermentation on the physicochemical properties, chemical structure, and antioxidant activity of the Lanzhou lily polysaccharide. The results showed that compared with the unfermented Lanzhou lily polysaccharide (LP-W), the molecular weight (M _w) of the fermented Lanzhou lily polysaccharide (LPF-W) decreased from 4334 to 1684 kDa, the particle size decreased from 300.8 ± 6.38 to 141.9 ± 4.96 nm, and the solubility increased from 72.33 ± 3.58 to 104.27 ± 2.91 mg/mL. In addition, after fermentation, the monosaccharide composition of LPF-W changed, and the alternation of mannose residues and glucose residues disappeared. The results of the analysis of the antioxidant activity in vitro showed that compared with LP-W, the fermented LPF-W had higher DPPH radical ability, superoxide anion radical scavenging ability, and reducing efficiency, but the hydroxyl radical scavenging ability decreased. These findings provide a reference for the potential application of the lily polysaccharide as a plant-derived antioxidant in functional foods.

Antihyperuricemic Effect of Green Alga Ulva lactuca Ulvan through Regulating Urate Transporters

A novel polysaccharide from Ulva lactuca (ULP) was purified using a Sepharose CL-4B column. Fourier transform infrared spectroscopy, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy were employed to analyze the structure of ULP. It consisted of rhamnose (Rha), glucuronic acid (GluA), galactose (Gal), and xylose (Xyl) at a molar ratio of 32.75:22.83:1.07:6.46 with the molecular weight of 2.24 × 10⁵ Da. The four major glycosidic residues found in ULP were →2,3)-α-l-Rhap-(1→, →4)-β-d-GlcpA-(1→, →2,6)-β-d-Galp-(1→, and →4)-β-d-Xylp-(1→. The antihyperuricemic activity of ULP was exhibited by detecting related biochemical indexes, urate transporter gene expressions, renal histopathology, and intestinal microbiota shifts. ULP obviously decreased the levels of serum uric acid (UA), blood urea nitrogen, and creatinine, while inhibited serum and hepatic xanthine oxidase activities as well as improved renal injury in hyperuricemic mice. Furthermore, the upregulation of UA excretion genes ABCG2/OAT1 and downregulation of UA resorption genes URAT1 and GLUT9 were detected. In addition, ULP exerted its antihyperuricemic effect through regulating the intestinal microbiome, characterized by elevating the helpful microbial abundance, meanwhile declining the harmful bacterial abundance and restoring the gut microbiome homeostasis. This study demonstrates the antihyperuricemic activity of ULP and its potential effect for the treatment of hyperuricemia-related diseases.

Structural characterization of novel arabinoxylan and galactoarabinan from citron with potential antitumor and immunostimulatory activities

This study aimed to extract polysaccharides from citron and analyze their structures and potential bioactivities. Two novel polysaccharides CM-1 and CM-2 were purified from citron by DEAE-Sepharose Fast Flow and Sephadex G-100 column chromatography. Monosaccharide composition, linkage and NMR data were used to infer their sugar chains composition. The anti-breast cancer cells and immunoregulatory activities of CM-1 and CM-2 were investigated. Results indicated that CM-1 (Mw = 21,520 Da), composed of arabinose, xylose, mannose and glucose in a molar ratio of 10.78:11.53:1.00:1.70, was arabinoxylan (AX) with (1 → 4)-linked β-d-Xylp skeleton monosubstituted with α-l-Araf units at O-3 position. While CM-2 (Mw = 22,303 Da), composed of arabinose, mannose, glucose and galactose in a molar ratio of 25.46:1.45:1.00:6.57, was galactoarabinan (GA) with (1 → 5)-linked α-l-Araf backbone substituted by β-d-Galp units at O-2 and/or O-3 positions. Both polysaccharides exhibited potential inhibiting cancer and immunostimulatory activities in vitro, especially CM-1. These results provide a basis for further research on citron polysaccharides.

Structural characterization and antioxidant activity of an acetylated Cyclocarya paliurus polysaccharide (Ac-CPP0.1)

The aim of this study was to investigate the primary structure of an acetylated Cyclocarya paliurus polysaccharide (Ac-CPP_0.1) and its protective effect on H₂O₂-treated dendritic cells. The backbone of Ac-CPP_0.1 was →3)-β-D-Galp-(1→, with some branches α-L-Araf-(1→ residues at O-6 and O-5, β-D-Galp-(1→ and 3,5,6)-β-D-Galf-(1 residues at O-4 and acetyl groups were substituted at the O-2 and O-6 positions of 3)-β-D-Galp-(1 residues. The CPP_0.1 and Ac-CPP_0.1 significantly increased the levels of superoxide dismutase, glutathione peroxidase and catalase on H₂O₂-treated dendritic cells. Meanwhile, both CPP_0.1 and Ac-CPP_0.1 up-regulated the expression of Nrf2 (NF-E2-related factor 2) and down-regulated the Keap1 (Kelch-like ECH-associated protein-1), but Ac-CPP_0.1 had a better effect on antioxidant capacity. These results indicated that potential application of Ac-CPP_0.1 as an antioxidant agent.

De novo sequencing of Bletilla striata (Orchidaceae) transcriptome and identification of genes involved in polysaccharide biosynthesis

Bletilla striata polysaccharide (BSP) is the main component of Bletilla striata, which has important pharmacological and pharmacological effects; however, due to the lack of genetic data, the metabolic pathways of BSP remain unclear. For this study, 11 representative resources of B. striata were analyzed, and the BSP contents of the different samples were significantly different; however, the monosaccharide composition of BSP was glucose and mannose. The representative samples were selected to observe their life history in situ, which were then divided and cultured in a greenhouse. Finally, samples from various organs of different plants were combined for transcriptome sequencing using the Illumina system. Our results summarized the BSP metabolic pathway, and we found that there were eight enzyme genes involved in biosynthesis, but these genes showed tissue specificity. Following qRT-PCR validation and comparative analysis, manA showed the highest expression; however, there were significant differences between the two germplasm resources in which the BSP content was significantly different, while UGP2, GPI, PMM, and GMPP had significant differences between the two samples. In summary, this study lays the foundation for further research into BSP metabolism and other physiological processes at the molecular level.

Extraction, purification, and determination of the gastroprotective activity of glucomannan from Bletilla striata

In this study, a water-soluble polysaccharide (BSP) was extracted and purified from pseudobulb of Bletilla striata. The preliminary structure and gastroprotective activity of BSP were analyzed. Results indicate that BSP is a glucomannan with a molar ratio of 7.45:2.55 (Man:Glc), and its molecular weight is approximately 1.7 × 10⁵ Da. BSP displayed outstanding protective action against ethanol-induced GES-1 cell injury in vitro, as well as, excellent gastroprotective activity in vivo. Especially, a high-dose of BSP (100 mg/kg) could reduce the ulcer index of the gastric mucosa and increase the percentage of ulcer inhibition, which possibly caused by enhancing the antioxidant capacity and inhibiting the apoptotic pathway in gastric tissue. Interestingly, BSP exhibited a comparative gastroprotective activity to that of positive control (omeprazole). In summary, our results indicated that BSP could be considered as a potential supplement for the prevention of gastric injury.

Optimizing the Extraction of Polysaccharides from Bletilla ochracea Schltr. Using Response Surface Methodology (RSM) and Evaluating their Antioxidant Activity

Bletilla ochracea Schltr. polysaccharides (BOP) have a similar structure to Bletilla striata (Thunb.) Reichb.f. (Orchidaceae) polysaccharides (BSP). Therefore, BOP can be considered as a substitute for BSP in the food, pharmaceuticals and cosmetics fields. To the best of our knowledge, little information is available regarding the optimization of extraction and antioxidant activity of BOP. In this study, response surface methodology (RSM) was firstly used for optimizing the extraction parameters of BOP. The results suggested that the optimal conditions included a temperature of 82 °C, a duration of 85 min and a liquid/material ratio of 30 mL/g. In these conditions, we received 26.45% ± 0.18% as the experimental yield. In addition, BOP exhibited strong concentration-dependent antioxidant abilities in vitro. The half-maximal effective concentration (EC50) values of BOP against 1,1-diphenyl-2-picrylhydrazyl (DPPH·), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonate) (ABTS+·), hydroxyl (·OH) and superoxide anion (·O2−) radicals and ferrous ions (Fe2+) were determined as 692.16, 224.09, 542.22, 600.53 and 515.70 µg/mL, respectively. In conclusion, our results indicate that BOP can be a potential natural antioxidant, deserving further investigation.