Structural characterization and biological activities of a novel polysaccharide containing N-acetylglucosamine from Ganoderma sinense

Extraction, purification, structural characterization, biological activity, mechanism of action and application of polysaccharides from Ganoderma lucidum: A review

Ganoderma lucidum is a traditional tonic medicine in China, known as the "fairy grass" and "spiritual grass". It contains various chemical components, such as polysaccharides, triterpenoids, alkaloids, nucleosides, sterols, and acid compounds, which have the effects of tonifying qi and calming the mind, stopping cough and asthma, and are used to treat restlessness, lung deficiency cough and asthma, fatigue and shortness of breath, and lack of appetite. Ganoderma lucidum polysaccharides (GLPs) are one of the main bioactive ingredients and are widely used in traditional Chinese medicine and traditional medicine fields. They have shown good medicinal value in enhancing immunity, inhibiting tumor cell growth, delaying aging, lowering blood sugar, lowering blood lipids, protecting the heart, anti-radiation, anti-fatigue, and other aspects. This article reviews the research progress on the extraction and purification, structural characteristics, pharmacological activity, and mechanisms of GLPs, as well as their applications in industries such as medicine, food, and daily chemical products. The aim is to provide theoretical basis for the treatment of traditional Chinese medicine compound preparations and lay the foundation for the potential value development of Ganoderma lucidum products.

Structural characterization of two novel heteropolysaccharides from Catharanthus roseus and the evaluation of their immunological activities

Catharanthus roseus, a plant with significant therapeutic value in Chinese folk medicine, contain numerous secondary metabolites. However, the primary metabolites, specifically polysaccharides which might play an important role in immunotherapy, have received limited attention. In the present study, two novel polysaccharides, designated as CRPS-1 and CRPS-2, were isolated from C. roseus. The structures of CRPS-1 and CRPS-2 were characterized using a combination of HPSEC, HPLC, IR, GC-MS, 1D NMR and 2D NMR. Both CRPS-1 and CRPS-2 were identified as homogeneous heteropolysaccharides. Additionally, the weight-average molecular weight of CRPS-2 was lower than that of CRPS-1. The backbone of CRPS-1 was composed of 1,3-α-L-Araf, 1,5-α-L-Araf, 1,3,5-α-L-Araf, 1,3,4-α-L-Rhap, 1,3-α-D-Galp, 1,3,4-α-D-Galp, 1,4-β-D-Manp, and side chains comprised of T-α-L-Araf, T-β-D-Manp, and β-D-Glcp-(1 → 3)-α-D-Galp-(1 → 3) -α-L-Rhap-(1→. CRPS-2 mainly consisted of 1,3-α-D-Galp, 1,3,4-α-D-Galp, 1,6-β-D-Manp, 1,5-α-L-Araf, 1,3,5-α-L-Araf, 1,3-α-L-Rhap and 1,3,4-α-L-Fucp with complex branching structures. Furthermore, CRPS-2 could significantly enhance proliferation and phagocytosis, as well as the secretion of cytokines in RAW264.7 cells. It demonstrated potent immunoregulatory activity by activating the MAPK/Akt/NF-κB signaling pathways. In summary, the utilization of galactose-enriched and low-molecular-weight polysaccharides exhibits great potential in the advancement of innovative functional foods that may provide health benefits.

A glucomannan from defatted Ganoderma lucidum spores: structural characterization and immunomodulatory activity via activating TLR4/MyD88/NF-κB signaling pathway

Ganoderma lucidum spores are tiny mature germ cells ejected from the abaxial side of the pileus and were responsible for multiple pharmacological properties. The defatted G. lucidum spores are the byproducts after the extraction of G. lucidum spores oil by supercritical fluid extraction technology, which have not been given sufficient attention. In order to fully utilize the resources of G. lucidum spores, a glucomannan (SGL90-1, 6.4 kDa) was isolated from the defatted G. lucidum spores. SGL90-1 was composed of mannose, glucose, galactose, and fucose in a molar ratio of 23.9:28.7:9.0:1.0. The backbone of SGL90-1 was consisted of →2,4)-α-D-Manp-(1→, →6)-β-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2)-α-D-Glcp-(1→, and →3,6)-β-D-Glcp-(1→ with seven side chains, and terminated with β-D-Manp-(1→, β-D-Glcp-(1→, α-L-Fucp-(1→, and β-D-Galf-(1→. Moreover, SGL90-1 could significantly elevate the phagocytic capability of RAW264.7 macrophages and promote the levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interlrukin-6 (IL-6) through activating the TLR4/MyD88/NF-κB signaling pathway. Collectively, these findings demonstrated the potential of SGL90-1 as a natural functional food with strong immune-enhancing effect.

Bioactivities and industrial standardization status of Ganoderma lucidum: A comprehensive review

Ganoderma lucidum (GL) is a potent source of bioactive compounds with diverse nutritional and pharmacological benefits. Its popularity as a dietary supplement, herbal remedy, and wellness product is steadily on the rise. Furthermore, the standardized advancement of the GL industry has facilitated reliable sourcing of raw materials and quality control measures, enhancing its utilization and endorsement in the realms of nutritional science and pharmaceutical research. This article provides a comprehensive overview of the recent advancements in research pertaining to the bioactive components of GL, particularly polysaccharides (GLP) and triterpenes (GLTs) as well as highlights the latest findings regarding their beneficial effects on human diseases, including anticancer, antidiabetes, liver protection and other aspects (such as regulating gut microbiota, antioxidant, antimicrobial, antiinflammatory and immune regulation). Furthermore, we summarized the potential applications of GL in the food and pharmaceutical sectors, while also examining the current status of standardization throughout the entire industrial chain of GL, both domestically and internationally. These information offer an insight and guidance for the prospects of industrial development and the innovative advancement of GL within the global health industry.

Structural characterization of polysaccharide from the peel of Trichosanthes kirilowii Maxim and its anti-hyperlipidemia activity by regulating gut microbiota and inhibiting cholesterol absorption

The peel of Trichosanthes kirilowii Maxim, is considered one of the primary sources for Trichosanthis pericarpium in traditional Chinese medicine, exhibiting lipid-lowering properties. The impact on hyperlipidemia mice of the crude polysaccharide from the peel of T. Kirilowii (TRP) was investigated in this study. The findings revealed that TRP exhibited a significant improvement in hepatic lipid deposition. Moreover, it significantly decreased serum levels of TC, TG, and LDL-C, while concurrently increasing HDL-C. 16S rRNA amplicon sequencing technique revealed that TRP group exhibited an increased relative abundance of Actinobacteria, a down-regulated relative abundance of Ruminiclostridium, and an up-regulated relative abundance of Ileibacterium. Therefore, TRP might play a role in anti-hyperlipidemia through regulation of the intestinal milieu and enhancement of microbial equilibrium. Consequently, targeted fractionation of TRP resulted in the isolation of a homogeneous acidic polysaccharide termed TRP-1. The TRP-1 polysaccharide, with an average molecular weight of 1.00 × 104 Da, and was primarily composed of Rha, GlcA, GalA, Glc, Gal and Ara. TRP-1 possessed a backbone consisting of alternating connections between → 6)-α-Galp-(1 → 4)-α-Rhap-(1 → 6)-α-Galp-(2 → 6)-β-Galp-(1 → 6)-α-Galp-(2 → 6)-β-Galp-(1 → units and branched chain containing → 6)-α-Glcp-(1→, 2,4)-β-Glcp-(1, and → 4)-α-GlapA-(1→. Both TRP and TRP-1 exhibited significant disruption of cholesterol micelles, highlighting their potential as lipid-lowering agents that effectively inhibit cholesterol absorption pathways.

Total Synthesis of Nona-decasaccharide Motif from Ganoderma sinense Polysaccharide Enabled by Modular and One-Pot Stereoselective Glycosylation Strategy

Polysaccharides from a medicinal fungus Ganoderma sinense represent important and adjunctive therapeutic agents for treating various diseases, including leucopenia and hematopoietic injury. However, the synthetic accessibility to long, branched, and complicated carbohydrates chains from Ganoderma sinense polysaccharides remains a challenging task in chemical synthesis. Here, we report the modular chemical synthesis of nona-decasaccharide motif from Ganoderma sinense polysaccharide GSPB70-S with diverse biological activities for the first time through one-pot stereoselective glycosylation strategy on the basis of glycosyl ortho-(1-phenyvinyl)benzoates, which not only sped up carbohydrates synthesis but also reduced chemical waste and avoided aglycones transfer issues inherent to one-pot glycosylation on the basis of thioglycosides. The synthetic route also highlights the following key steps: (1) preactivation-based one-pot glycosylation for highly stereoselective constructions of several 1,2-cis-glycosidic linkages, including three α-d-GlcN-(1 → 4) linkages and one α-d-Gal-(1 → 4) bond via the reagent N-methyl-N-phenylformamide modulation; (2) orthogonal one-pot assembly of 1,2-trans-glycosidic linkages in various linear and branched glycans fragments by strategic combinations of glycosyl N-phenyltrifluoroacetimidates, glycosyl ortho-alkynylbenzoates, and glycosyl ortho-(1-phenyvinyl)benzoates; and (3) the final [1 × 4 + 15] Yu glycosylation for efficient assembly of nona-decasaccharide target. Additionally, shorter sequences of 4-mer, 5-mer, and 6-mer are also prepared for structure-activity relationship biological studies. The present work shows that this one-pot stereoselective glycosylation strategy can offer a reliable and effective means to streamline chemical synthesis of long, branched, and complex carbohydrates with many 1,2-cis-glycosidic bonds.

Dendrobium officinale flowers' topical extracts improve skin oxidative stress and aging

BACKGROUND

Dendrobium officinale flowers (DOF) have the effects of antiaging and nourishing yin, but it lacks pharmacological research on skin aging.

OBJECTIVE

Confirming the role of DOF in delaying skin aging based on the "in vitro animal-human" model.

METHODS

In this experiment, three kinds of free radical scavenging experiments in vitro, D-galactose-induced aging mouse model, and human antiaging efficacy test were used to test whether DOF can improve skin aging through anti-oxidation.

RESULTS

In vitro experiment shows that DOF has certain scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, hydroxyl free radical, and superoxide free radical, and its IC50 is 0.2090 μg/mL, 15.020, and 1.217 mg/mL respectively. DOF can enhance the activities of T-AOC, SOD, CAT, and GSH Px in the serum of aging mice, increase the content of GSH, and reduce the content of MDA when administered with DOF of 1.0, 2.0, and 4.0 g/kg for 6 weeks. In addition, it can enhance the activity of SOD in the skin of aging mice, increase the content of Hyp, and decrease the content of MDA, activated Keap1/Nrf2 pathway in the skin of aging mice. Applying DOF with a concentration of 0.2 g/mL on the face for 8 weeks can significantly improve the skin water score and elasticity value, reduce facial wrinkles, pores, acne, and UV spots, and improve the facial brown spots and roughness.

CONCLUSION

DOF can significantly improve skin aging caused by oxidative stress, and its mechanism may be related to scavenging free radicals in the body and improving skin quality.

Functional properties of Ganoderma lucidum supplementation in canine nutrition

Ganoderma lucidum (GL) is a mushroom that has been widely used in Asia for its immunostimulatory and anti-inflammatory capacity, which has been hypothesized to be attributed mainly to the recognition of its cell-surface patterns by cells of the immune system present in the gastrointestinal tract, resulting in a cascade of modulatory events. However, the nutraceutical properties of GL have not been tested in dogs. Forty adult beagles were used in a completely randomized design. The objective of the present study was to evaluate the effects of dietary inclusion of GL on peripheral blood mononuclear cells (PBMC; T cells, B cells, monocytes, and natural killers), vaccine response, nutrient digestibility, fecal fermentative end-products, and skin and coat quality of adult dogs. Dogs were fed a commercial dry extruded complete and balanced diet plus GL top-dressed daily upon feeding time. Four experimental treatments were used: 0% GL supplementation (control), 5 mg/kg BW of GL, 10 mg/kg BW of GL, or 15 mg/kg BW of GL. Following a 7 d adaptation to the control diet, dogs were fed their respective treatment diets for 28 d. They were challenged with vaccination of a modified live virus Canine Distemper, Adenovirus Type 1 (Hepatitis), Adenovirus Type 2, Parainfluenza, and Parvovirus and killed Rabies Virus on day 7 with blood collections on days 0, 14, and 28. The inclusion of GL in all dosages was well-accepted by all dogs, with no detrimental effect on macronutrient apparent total tract digestibility. There was a trend that the percentage of major histocompatibility II (MHC-II) from B cells was greater in dogs fed 15 mg/kg of GL (41.91%) compared to the control group (34.63%). The phagocytosis response tended to have treatment-by-time interaction among treatments; dogs fed 15 mg/kg of GL tended to have greater phagocytosis activity on day 28 than dogs from the control group and dogs fed 5 mg/kg of GL. The vaccine-specific serum immunoglobulin G (IgG) concentrations were higher in the group supplemented with 15 mg/kg of GL compared to treatment control 7 d after the vaccination for rabies. These data suggest that the inclusion of GL had no detrimental effects on any analyzed PBMC. Due to changes in immune parameters among treatments, GL may also exert beneficial immunostimulatory effects in healthy adult dogs when provided at a daily dose of 15 mg/ kg BW.

Ganoderma spp. polysaccharides are potential prebiotics: a review

The gut microbiota (GM) is a complex ecosystem that is closely linked to host health. Ganoderma spp. polysaccharides (GPs), a major bioactive component of the fungal genus Ganoderma, can modulate the GM, exhibiting various health effects and prebiotic potential. This review comprehensively concluded the structural features and extraction method of GPs. The mechanism of GPs for anti-obesity, anti-diabetes, anti-inflammatory, and anti-cancer were further evaluated. The simulated gastrointestinal digestion of GPs and the utilization mechanism of host microorganisms were discussed. It was found that the physicochemical properties and biological activities of GPs depend on their structural characteristics (molecular weight, monosaccharide composition, glycosidic bonds, etc.). Their extraction method also affects the structure and bioactivities of polysaccharides. GPs supplementation could increase the relative abundance of beneficial bacteria (e.g. Bacteroides, Parabacteroides, Akkermansia, and Bifidobacterium), while reducing that of pathogenic bacteria (e.g. Aerococcus, Ruminococcus), thus promoting health. Moreover, GPs are resistant to digestion in the stomach and small intestine but are digested in the large intestine. Therefore, GPs can be considered as potential prebiotics. However, further studies should investigate how GPs as prebiotics regulate GM and improve host health.

Structural characterization and immunoregulatory activity of a novel acidic polysaccharide from Scapharca subcrenata

A novel acidic polysaccharide named SSPA50-1 was isolated from Scapharca subcrenata using a simulated gastric fluid extraction method. SSPA50-1 is a heteropolysaccharide with an average molecular weight of 44.7 kDa that is composed of galacturonic acid, glucose, galactose, mannose, ribose, rhamnose, fucose, xylose and arabinose at a molar ratio of 1.00:5.40:9.04:3.10:1.59:4.01:2.10:2.21:2.28. The structural characterization based on the methylation and 1D/2D NMR analyses indicated that SSPA50-1 is composed of →3)-β-L-Rhap-(1→, →3)-β-L-2-O-Me-Fucp-(1→, →2)-α-D-Xylp-(1→, →5)-α-L-Araf-(1→, →3)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →3,4)-β-D-Manp-(1→, →3,4)-β-D-Galp-(1→, β-D-Ribf-(1→, α-D-Glcp-(1→, and α-D-GalAp6Me-(1→. Furthermore, SSPA50-1 possessed potent immunoregulatory activity by enhancing the phagocytosis and NO, iNOS, TNF-α and IL-6 secretion capacity of RAW264.7 cells. Otherwise, SSPA50-1 significantly promoted the proliferation of splenic lymphocytes and RAW264.7 macrophages. These results indicated that SSPA50-1 could be developed as a potential ingredient for immunostimulatory agents.

Polysaccharides from Basidiocarps of the Polypore Fungus Ganoderma resinaceum: Isolation and Structure

In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L-1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-β-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-β-d-glucan. Mannogalactan predominated in the cold water extract, and β-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched β-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-β-d-glucan having terminal β-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and β-d-glucans.

Isotope-Coding Derivatization for Quantitative Profiling of Reactive α-Dicarbonyl Species in Processed Botanicals by Liquid Chromatography-Tandem Mass Spectrometry

α-Dicarbonyls (α-DCs) are key reactive Maillard intermediates with structural diversity and are widely found in foods and in vivo, but little is known regarding the complete molecular profiles of these potentially harmful electrophiles. Herein, we reported a novel isotope-coding derivatization (ICD) strategy for the broad-spectrum, quantitative profiling of (non)target α-DC species in natural foodstuffs. It utilized differential isotope labeling (DIOL) with a reagent pair o-phenylenediamine (OPD)/OPD-d₄ (deuterated) to form stable quinoxalines for class-specific fragmentation-dependent acquisition using liquid chromatography-hybrid quadrupole linear ion trap mass spectrometry (LC-QqLIT). A combination of facile one-pot quantitative labeling and convenient cleanup protocol afforded satisfactory sensitivity, linearity, accuracy (81-116%), and process recovery (86-109% with RSDs < 10%) by matrix-matched ICD-internal standard calibration, without significant matrix interference (-9 to 5%), isotopic effect (<0.5%), and cocktail effect. A more generic DIOL-based LC-QqLIT algorithm integrated double precursor ion and neutral loss scan to trigger enhanced product ions with the unique isobaric doublet tags (4 Da shift), enabling simultaneous screening and relative quantitation of nontarget α-DC analogues in a single analysis. This study has widened the vision on complex α-DC profiles in traditional botanicals, which revealed a wide occurrence of α-DCs in such processed sugar-rich products, yet their abundance varied greatly among different samples.

Characterization of a polysaccharide from the medicinal lichen, Usnea longissima, and its immunostimulating effect in vivo

A polysaccharide, CSL-0.1, was isolated from the medicinal lichen, Usnea longissima. CSL-0.1 was a neutral rhamnose-containing glucogalactomannan with a molecular weight of 7.86 × 104 Da. The polysaccharide had a core mannan structure with (1 → 6)-α-d-Manp units as the main chain and was substituted at the O-2 positions with side chains containing (1 → 2)-α-d-Manp residue, [3)-α-Glcp(1 → 4)-α-Glcp(1→] and 6-O-substituted β-d-Galf units. 2-O- and 2,3-di-O-substituted Rhap units. The effects of CSL-0.1 on intestinal immunity and antioxidant activity were evaluated. CSL-0.1 increased the spleen and thymus indices in a dose-dependent manner and conferred immunomodulation on reversing the Th1/Th2-related cytokine imbalance in cyclophosphamide (CP)-induced immunosuppressed mice. CSL-0.1 could also enhance the levels of secretory immunoglobulin A in CP-injected mice. Additionally, the antioxidant levels in the liver and intestine of the mice were increased 20%-50% after intragastric injection by CSL-0.1.

Isolation, structural characterization, and biological activities of galactomannans from Rhizopogon luteolus and Ganoderma adspersum mushrooms

Polysaccharides are essential compounds that contribute to the biological activities of mushrooms. Two new galactomannans (Galactomannan I and II) were isolated from R. luteolus and G. adspersum. Their structures were characterized using FT-IR, 1D, and 2D-NMR techniques. Both isolated galactomannans I and II mainly include D-mannose and D-galactose in the molar percentages of 0.81:1.0 and 1:1.4, respectively. The GPC calculation demonstrated that the molecular weights are about 5240 and 5090 Da, respectively. Their structures comprise of β-(1,4)-mannose (Man) backbone units with α-(1,6)-galactose (Gal) single unit as a side group. The anticholinesterase activity of galactomannans was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), spectrophotometrically. Antioxidant activity was also measured by six assays (ABTS^•+, DPPH^•, O₂^•-, β-carotene-linoleic acid, metal chelating, and CUPRAC assays). Galactomannan II indicated close inhibitory activity to galantamine against AChE (61.04 ± 0.45%) and BChE (59.70 ± 1.15%) at 50 μg/mL concentration. Nevertheless, both galactomannans showed low antioxidant activity in all tests. This study reveals that mainly, Galactomannan II could be used as a new natural promising anticholinesterase agent.