Structural investigation of a novel fucoglucogalactan isolated from the fruiting bodies of the fungus Hericium erinaceus

Hericinosides A-M, Cyathane Diterpene Glycosides with α-Glucosidase Inhibitory Activity from the Medicinal Fungus Hericium erinaceus

Thirteen new cyathane diterpene glycosides, hericinosides A-M (1-13), and six known analogs, were isolated from the rice media fermentation of the medicinal fungus Hericium erinaceus. The sugar parts of 1 and 2 were highly modified, forming a unique 5/6/7/5/5/5 ring new skeleton system. All structures were elucidated based on spectroscopic data, and their relative configurations were determined according to the ROESY analysis. Possible biosynthetic pathways for compounds 1-13 were discussed. Compounds 6 and 19 showed significant α-glucosidase inhibitory activity with IC50 values of 82.7 and 199.5 μM, respectively. The results will facilitate further studies to expand the use of diterpene glycosides from this mushroom for actual and potential biological properties in metabolic regulation.

Evaluation of the "Relative Ordered Structure of Hericium erinaceus Polysaccharide" from Different Origins: Based on Similarity and Dissimilarity

Polysaccharides are organic compounds widely distributed in nature, but structural order and disorder remain a formidable problem. In this study, based on the theoretical framework of the "relative ordered structure of polysaccharide" proposed in our previous work, the structural order of Hericium erinaceus polysaccharides from different regions was evaluated by FT-IR, methylation analysis, and 1H NMR spectroscopy combined with chemometric methods. The results of principal component analysis and heatmap cluster analysis revealed that 18-subfractions exhibit four different structural types with representative glycoside linkage types: fucogalactoglucan, glucofucogalactan, fucoglucan, and glucan. The main chain of heteroglucans often consists of β-(1 → 6)-Glcp, β-(1 → 4)-Glcp, and β-(1 → 3)-Glcp residues, which are predominantly substituted at the O-3 and O-6 positions. The main chain structure of heterogalactans is α-(1 → 6)-Galp residues, which may be replaced by Fucp and Galp residues at O-2. Overall, our findings demonstrate the validity of the "relative ordered structure of polysaccharide" in Hericium erectus polysaccharides and simplify the complexity of polysaccharide structures.

Low Weight Polysaccharide of Hericium erinaceus Ameliorates Colitis via Inhibiting the NLRP3 Inflammasome Activation in Association with Gut Microbiota Modulation

Ulcerative colitis (UC), one of the typical inflammatory bowel diseases caused by dysregulated immunity, still requires novel therapeutic medicine with high efficacy and low toxicity. Hericium erinaceus has been widely used to treat different health problems especially gastrointestinal sickness in China for thousands of years. Here, we isolated, purified, and characterized a novel low weight polysaccharide (HEP10, Mw: 9.9 kDa) from the mycelia of H. erinaceus in submerged culture. We explored the therapeutic effect of HEP10 on UC and explored its underlying mechanisms. On one hand, HEP10 suppressed the production of TNF-α, IL-1β, IL-6, inducible iNOS, and COX-2 in LPS challenged murine macrophage RAW264.7 cells, as well as in colons from DSS-induced colitis mice. On the other hand, HEP10 treatment markedly suppressed the activation of NLRP3 inflammasome, NF-κB, AKT, and MAPK pathways. Moreover, HEP10 reversed DSS-induced alternation of the gut community composition and structure by significantly increasing Akkermansia muciniphila and also promoting functional shifts in gut microbiota. Structural equation modeling also highlighted that HEP10 can change widely through gut microbiota. In conclusion, HEP10 has a better prebiotic effect than the crude polysaccharides of H. erinaceus, which can be used as a novel dietary supplement and prebiotic to ameliorate colitis.

Fungi and Algae as Sources of Medicinal and Other Biologically Active Compounds: A Review

Many species of fungi including lichenized fungi (lichens) and algae have the ability to biosynthesize biologically active compounds. They produce, among others, polysaccharides with anticancer and immunostimulatory properties: (1) Background: This paper presents the characteristics of the most important bioactive compounds produced by fungi and algae; (2) Methods: Based on the example of the selected species of mushrooms, lichens and algae, the therapeutic properties of the secondary metabolites that they produce and the possibilities of their use are presented; (3) Results: The importance of fungi, especially large-fruited mushrooms, lichens and algae, in nature and human life is discussed, in particular, with regard to their use in the pharmaceutical industry and their nutritional value; (4) Conclusions: The natural organisms, such as fungi, lichenized fungi and algae, could be used as supplementary medicine, in the form of pharmaceutical preparations and food sources. Further advanced studies are required on the pharmacological properties and bioactive compounds of these organisms.

Structural Identification and Coagulation Effect of Flammulina velutipes Polysaccharides

Two polysaccharides were isolated successfully from Flammulina velutipes and identified as CHFVP-1 (24.44 kDa) and CHFVP-2 (1497 kDa). Based on the results of Fourier transform-infrared spectroscopy (FT-IR), gas chromatography (GC), gas chromatography–mass spectrometry (GC–MS), and nuclear magnetic resonance (NMR) spectroscopy regarding the structure of CHFVP-1 and CHFVP-2, CHFVP-1 was constructed with the backbone of→6)-α-D-Galp-(1→ and the branch of Galp by an →3,6)-α-D-Manp-(1→attached with T-β-D-Glcp or t-α-L-Fucp side chains. Meanwhile, the CHFVP-2 was a glucan with the construction of →6)-β-D-Glcp-(1→ and T-β-D-Glcp. Moreover, the coagulant activity in vitro of CHFVP-1 and CHFVP-2 was evaluated, and the results showed that CHFVP-1 exerts procoagulant activity by shortening the activated partial thromboplastin time (APTT) and thrombin time (TT), while CHFVP-2 did not reveal a definite coagulant activity. The finding would benefit the further application of F. velutipes in the field of medicine.

Structure and immunostimulating activity of a galactofuranose-rich polysaccharide from the bamboo parasite medicinal fungus Shiraia bambusicola

ETHNOPHARMACOLOGICAL RELEVANCE

Shiraia bambusicola is a parasitic fungus on the twigs of bamboos. Its relatively large stroma has high medicinal value and can treat a variety of diseases such as rheumatoid arthritis, cold stomach pain, sciatica, injuries, chronic bronchitis, and infantile. It is widely distributed in many provinces in Southern China and also is also found in Japan.

AIM OF THE STUDY

Medicinal fungi were important resources for bioactive polysaccharides. To explore bioactive polysaccharides from Shiraia bambusicola, a heteropolysaccharide SB2-1 was purified and obtained from S. bambusicola and its immunostimulating activity was researched.

MATERIALS AND METHODS

The polysaccharide from S. bambusicola was extracted and purified using enzyme assisted extraction, ethanol precipitation, anion-exchange and size-exclusion chromatography. Molecular weight of polysaccharide was estimated by high performance gel permeation chromatography. Monosaccharide compositions were determined by high performance liquid chromatography after pre-column derivatization and UV detection. Structure information was elucidated by IR spectrum, GC-MS analysis after methylation and gradual acid hydrolysis of the polysaccharide. The RAW264.7 cells were used to study the immunostimulating activity in vitro.

RESULTS

Physicochemical and structural analyses showed that SB2-1 was a neutral heteropolysaccharide with molecular weight at 22.2 kDa and consisted of glucose, galactose and mannose at a ratio of 2.0:1.5:1.0. The structure of SB2-1 was a branched polysaccharides composed of a mannan core and side chains consisted of glucose and galactose. The mannan core was composed of (1→2)-Manp as the main chain. Glucose with (1→4)-D-Glcp, (1→2)-D-Glcp and (1→6)-D-Glcp at different degrees of polymerization were linked at C-6 and C-3 of the (1→2)-Manp as the side chains. The galactose with the linages of (1→6)-D-Galf, →2)-D-Galf(1→ and terminal D-Galf(1→ also existed in the side chain. The study on the immunostimulating activities of SB2-1 and its core structure P-2 were investigated on RAW264.7 macrophages. The results showed that SB2-1 could activate RAW264.7 macrophage and significantly improve its phagocytic ability by neutral red uptake experiment. Meanwhile, SB2-1 increased significantly higher inducible nitric oxide synthase (iNOS) production and the productions of IL-1, IL-6, IL-12 and TNF-α. The effect of SB2-1 was better than its core structure P-2 produced by gradual acid hydrolysis, which meant the side chains played an important role in the immunostimulating activities.

CONCLUSIONS

The investigation demonstrated that the galactofuranose-containing mannogalactoglucan was characteristic polysaccharides in S. bambusicola and could enhance the activation of macrophages.

Effects of Rich in Β-Glucans Edible Mushrooms on Aging Gut Microbiota Characteristics: An In Vitro Study

Alterations of gut microbiota are evident during the aging process. Prebiotics may restore the gut microbial balance, with β-glucans emerging as prebiotic candidates. This study aimed to investigate the impact of edible mushrooms rich in β-glucans on the gut microbiota composition and metabolites by using in vitro static batch culture fermentations and fecal inocula from elderly donors (n = 8). Pleurotus ostreatus, P. eryngii, Hericium erinaceus and Cyclocybe cylindracea mushrooms derived from various substrates were examined. Gut microbiota composition (quantitative PCR (qPCR)) and short-chain fatty acids (SCFAs; gas chromatography (GC)) were determined during the 24-h fermentation. P. eryngii induced a strong lactogenic effect, while P. ostreatus and C. cylindracea induced a significant bifidogenic effect (p for all <0.05). Furthermore, P. eryngii produced on wheat straw and the prebiotic inulin had comparable Prebiotic Indexes, while P. eryngii produced on wheat straw/grape marc significantly increased the levels of tested butyrate producers. P. ostreatus, P. eryngii and C. cylindracea had similar trends in SCFA profile; H. erinaceus mushrooms were more diverse, especially in the production of propionate, butyrate and branched SCFAs. In conclusion, mushrooms rich in β-glucans may exert beneficial in vitro effects in gut microbiota and/or SCFAs production in elderly subjects.

Structure characterization of a novel polysaccharide from Hericium erinaceus fruiting bodies and its immunomodulatory activities

Hericium erinaceus polysaccharide (HEP-S) can significantly stimulate the immunomodulatory activity on murine macrophages and spleen lymphocytes.

The structure of mushroom polysaccharides and their beneficial role in health

Mushroom is a kind of fungus that has been popular for its special flavour and renowned biological values. The polysaccharide contained in mushroom is regarded as one of the primary bioactive constituents and is beneficial for health. The structural features and bioactivities of mushroom polysaccharides have been studied extensively. It is believed that the diverse biological bioactivities of polysaccharides are closely related to their structure or conformation properties. In this review, the structural characteristics, conformational features and bioactivities of several mushroom polysaccharides are summarized, and their beneficial mechanisms and the relationships between their structure and bioactivities are also discussed.

Structure elucidation of a bioactive polysaccharide from fruiting bodies of Hericium erinaceus in different maturation stages

HPB-3, a heteropolysaccharide, with a mean molecular weight of 1.5×10(4)Da, was obtained from the maturating-stage IV, V and VI fruiting body of Hericium erinaceus, exhibited higher macrophages stimulation activities, was able to upregulate the functional events mediated by activated macrophages, such as production of nitric oxide (NO). Monosaccharide composition analysis showed that HPB-3 comprised l-fucose, d-galactose and d-glucose in the ratio of 5.2:23.9:1. Its chemical structure was characterized by sugar and methylation analysis, along with (1)H and (13)C NMR spectroscopy, including (1)H-(1)H COSY, TOCSY, NOESY, HMQC and HMBC experiments. The results indicated that HPB-3 contained a-(1/6)-linked galactopyranosyl backbone, partially with a side chain composed of α-l-fucopyranose at the O-2 position. The predicted primary structure of the polysaccharide was established as below.

A polysaccharide from cultured mycelium of Hericium erinaceus and its anti-chronic atrophic gastritis activity

A polysaccharide named EP-1 was found by screening cultured mycelium of Hericium erinaceus, which was extracted and subjected to precipitation with ethanol, hollow-fiber ultrafiltration and ion-exchange chromatography. The polysaccharide has a molecular weight of approximately 3100Da and is composed of glucose, mannose and galactose, thus being a heteroglycan. EP-1 has a backbone of α-d-Glc(1→3) and β-d-Glc(1→3). The β-d-Glc(1→3) and α-d-Gal-(1→3) were regarded as branches attached to the C-4 position. The α-d-Man was regarded as a terminal residue. The anti-CAG activity was evaluated in experimental systems using a cell model for identification. The polysaccharide significantly inhibited the growth of MC cells obtained from human gastric mucosa epithelium (GES-1) cells transformed by MNNG, which were used as a chronic atrophic gastritis cell model. It also interfered with the MC cells by inducing cell cycle arrest. Thus, EP-1 shows potential for the development of new functional foods and drugs.

Chemistry, Nutrition, and Health-Promoting Properties of Hericium erinaceus (Lion's Mane) Mushroom Fruiting Bodies and Mycelia and Their Bioactive Compounds

The culinary and medicinal mushroom Hericium erinaceus is widely consumed in Asian countries, but apparently not in the United States, for its nutritional and health benefits. To stimulate broader interest in the reported beneficial properties, this overview surveys and consolidates the widely scattered literature on the chemistry (isolation and structural characterization) of polysaccharides and secondary metabolites such as erinacines, hericerins, hericenones, resorcinols, steroids, mono- and diterpenes, and volatile aroma compounds, nutritional composition, food and industrial uses, and exceptional nutritional and health-promoting aspects of H. erinaceus. The reported health-promoting properties of the mushroom fruit bodies, mycelia, and bioactive pure compounds include antibiotic, anticarcinogenic, antidiabetic, antifatigue, antihypertensive, antihyperlipodemic, antisenescence, cardioprotective, hepatoprotective, nephroprotective, and neuroprotective properties and improvement of anxiety, cognitive function, and depression. The described anti-inflammatory, antioxidative, and immunostimulating properties in cells, animals, and humans seem to be responsible for the multiple health-promoting properties. A wide range of research advances and techniques are described and evaluated. The collated information and suggestion for further research might facilitate and guide further studies to optimize the use of the whole mushrooms and about 70 characterized actual and potential bioactive secondary metabolites to help prevent or treat human chronic, cognitive, and neurological diseases.

Enhancement of the neuroprotective activity of Hericium erinaceus mycelium co-cultivated with Allium sativum extract

This study investigated the neuroprotective effects of Hericium erinaceus mycelium enriched with garlic extract (HGE) on rat pheochromocytoma nerve cells (PC12). The survival rates of the PC12 nerve cells and the neurite-bearing cells after the addition of HGE were estimated as 3.5 × 10(3) viable cells/ml and 2.3 × 10(3) viable cells/ml, respectively, which were 50% and 30% higher, respectively, compared with the untreated group. For the in vivo ischemia experiments, after treatment with the HGE extract, the hippocampal CA1 region was more strongly stained (>20%) than the control group, and the HGE extract also promoted higher staining levels than HFB, HM and HGEF, and even the garlic extract. This result indicates that HGE must have neuroprotective effects. Furthermore, HGE greatly decreased p21 gene expression to approximately 70% of the control and decreased p21 gene expression to even lower levels compared with HM, HGEF and the garlic extract. This work suggests that a synergistic effect of the H. erinaceus mycelium and the garlic extract (mainly allicin) exist because the amount of allicin in HGE (5.81 µg/ml) was lower than the garlic extract itself (6.89 µg/ml).

Hericium erinaceus (Yamabushitake): a unique resource for developing functional foods and medicines

This article provides valuable scientific information for Hericium erinaceus and shows its potential for the development of new functional foods and drugs.

Influence of inorganic and organic selenium on number of living mycelial cells and their ultrastructure in culture of Hericium erinaceum (Bull.: Fr. Pers.)

Mycelium of the white-rot fungus (Hericium erinaceum (Bull.: Fr. Pers.) produces polysaccharides showing anticancer and immunostimulating activity. In our previous works, we have shown that organic selenitetriglycerides (Selol) contribute to the increase of biosynthesis of exopolysaccharides (EPS) having antioxidative properties and containing large amounts of selenium. The present work is a study of influence of inorganic and organic form of selenium on viability of H. erinaceum mycelium and on ultrastructural changes taking place during its development in submerged culture. The mycelium was grown on media containing sodium selenite (Na2SeO3), a mixture of Na2SeO3 + Selol2% and on control medium (no selenium added). It was shown that mycelium cultured for 3 days in control conditions on standard media contained almost 100% of living cells, with over 80% after 24 days. Treatment with 100 ppm of Na2SeO3 lowered the number of viable cells to 11.8% and 9.1% after 3 and 24 days, respectively. The addition of 2% Selol caused the amounts of living cells to remain at ca 90%. Apparently, Selol helped the cells to cope with the toxic activity of inorganic selenium ions. The addition of sodium selenite induced degradative changes in cell organelles. Such changes were not observed in the case of Na2SeO3 + Selol mixture, in which case cells contained numerous ribosomes and small lipid bodies.

A 3-O-methylated mannogalactan from Pleurotus pulmonarius: structure and antinociceptive effect

A polysaccharide (Mw 2.39x10(4)g/mol) was extracted with cold water from the basidiomycete Pleurotus pulmonarius, and its antinociceptive and anti-inflammatory properties were evaluated. It was a mannogalactan (MG), whose structure was characterized using mono- and two-dimensional NMR spectroscopy, methylation analysis, and a controlled Smith degradation. It had a main chain of (1-->6)-linked alpha-D-galactopyranosyl and 3-O-methyl-alpha-D-galactopyranosyl units, both of which are partially substituted at O-2 by beta-D-mannopyranosyl non-reducing ends. The MG was tested for its effects on the acetic acid-induced writhing reaction in mice, a typical model for inflammatory pain, causing a marked and dose-dependent inhibition of the nociceptive response, with ID50 of 16.2 (14.7-17.7)mg/kg and inhibition of 93+/-3% at a dose of 30mg/kg. An inflammatory response was not inhibited.