A Review of Development and Utilization for Edible Fungal Polysaccharides: Extraction, Chemical Characteristics, and Bioactivities

Discarded enoki mushroom root-derived multifunctional chrome-free chitosan-based tanning agent for eco-leathers manufacturing: Tanning-dyeing, non-acid soaking, and non-basifying

The aim of this study was to develop new discarded enoki mushroom root-derived multifunctional chrome-free chitosan-based tanning agents that can be used for eco-leather manufacturing. In this study, oligochitosan (OCS) was prepared from chitosan extracted from the enoki mushrooms and chemically modified using reactive dye R19 and epichlorohydrin (ECH) to prepare chromium-free tanning agent (OCS-R19-ECH) with both tanning and dyeing functions. FT-IR, XRD, and NMR (1H) confirmed the successful synthesis of the product. The molecular weight of OCS-R19-ECH is 6355 g/mol, with an average particle size of 1249.37 nm and an epoxy value of 0.276 mol/100 g. OCS-R19-ECH was used for tanning experiments on bated sheepskin, and the results showed that the leather tanned with OCS-R19-ECH not only exhibited excellent wet-heat stability (shrinkage temperature = 81 °C), but also superior dyeing uniformity, resistance to dry and wet abrasion, mechanical strength (tensile strength = 12.4 MPa, tear strength = 57.3 N/mm), and outstanding antimicrobial properties. Most importantly, compared with traditional tanning agents, OCS-R19-ECH has a higher pH (9.0), tanning-dyeing integration, non-acid soaking, and non-basifying can be achieved in leather making, which can greatly simplify the tanning processes. This new multifunctional chrome-free chitosan-based tanning agent facilitates high-value utilization of waste resources.

Recent Advances in the Application of Natural Products for Postharvest Edible Mushroom Quality Preservation

Edible mushrooms are favored by consumers for their excellent nutritional value and pharmacological properties. However, fresh mushrooms are highly perishable and undergo rapid quality deterioration induced by a series of intrinsic and extrinsic factors during postharvest storage. In recent years, the application of natural products derived from plants, animals, microorganisms, and other sources in mushroom quality preservation has drawn increasing attention. Compared to chemical preservatives, natural products show similar or higher biological activity and have few side effects on human health. This review summarizes the recent advances in the application of natural products used for quality maintenance of postharvest mushrooms. These natural substances mainly include essential oils, polyphenols, polysaccharides, bacteriocins, and other extracts. They have the potential to inhibit mushroom weight loss, softening, and browning, reduce the count of pathogenic microorganisms, and retain nutrients and flavor, effectively improving the quality of mushrooms and extending their shelf-life. The preservation techniques for natural products and their preservation mechanisms are also discussed here. Overall, this review provides current knowledge about natural products in edible mushroom preservation and aims to inspire more in-depth theoretical research and promote further practical application.

Anti-inflammatory properties of polysaccharides from edible fungi on health-promotion: a review

Edible fungus polysaccharides have garnered significant attention from scholars due to their safety and potential anti-inflammatory activity. However, comprehensive summaries of their anti-inflammatory properties are still rare. This paper provides a detailed overview of the anti-inflammatory effects and mechanisms of these polysaccharides, as well as their impact on inflammation-related diseases. Additionally, the relationship between their structure and anti-inflammatory activity is discussed. It is believed that this review will greatly enhance the understanding of the application of edible fungus polysaccharides in anti-inflammatory treatments, thereby significantly promoting the development and utilization of edible fungi.

Characterization of Polysaccharide Extracts of Four Edible Mushrooms and Determination of In Vitro Antioxidant, Enzyme Inhibition and Anticancer Activities

Mushroom polysaccharides are important bioactive compounds derived from mushrooms with various beneficial properties. In this study, the chemical characterization and bioactivities of polysaccharide extracts from four different edible mushrooms, Clavariadelphus truncatus Donk, Craterellus tubaeformis (Fr.) Quél., Hygrophorus pudorinus (Fr.) Fr., and Macrolepiota procera (Scop.) Singer were studied. Glucose (13.24-56.02%), galactose (14.18-64.05%), mannose (2.18-18.13%), fucose (1.21-5.78%), and arabinose (0.04-5.43%) were identified in all polysaccharide extracts by GC-MS (gas chromatography-mass spectrometry). FT-IR (Fourier transform infrared spectroscopy) confirmed the presence of characteristic carbohydrate patterns. 1H NMR suggested that all polysaccharide extracts had α- and β-d-mannopyranose, d-glucopyranose, d-galactopyranose, α-l-arabinofuranose, and α-l-fucopyranose residues. Approximate molecular weights of polysaccharide extracts were determined by HPLC (high-performance liquid chromatography). The best antioxidant activity was found in M. procera polysaccharide extract in DPPH• (1,1-diphenyl-2-picrylhydrazyl) scavenging (39.03% at 800 μg/mL), CUPRAC (cupric reducing antioxidant capacity) (A0.50: 387.50 μg/mL), and PRAP (phosphomolybdenum reducing antioxidant power) (A0.50: 384.08 μg/mL) assays. C. truncatus polysaccharide extract showed the highest antioxidant activity in ABTS•+ scavenging (IC50: 734.09 μg/mL), β-carotene-linoleic acid (IC50: 472.16 μg/mL), and iron chelating (IC50: 180.35 μg/mL) assays. Significant anticancer activity was found in C. truncatus polysaccharide extract on HT-29 (IC50: 46.49 μg/mL) and HepG2 (IC50: 48.50 μg/mL) cell lines and H. pudorinus polysaccharide extract on the HeLa cell line (IC50: 51.64 μg/mL). Also, H. pudorinus polysaccharide extract possessed prominent AChE (acetylcholinesterase) inhibition activity (49.14% at 200 μg/mL).

Glucans and applications in drug delivery

Glucan is a natural polysaccharide widely distributed in cereals and microorganisms that has various biological activities, including immunomodulatory, anti-infective, anti-inflammatory, and antitumor activities. In addition to wide applications in the broad fields of food, healthcare, and biomedicines, glucans hold promising potential as drug delivery carrier materials or ligands. Specifically, glucan microparticles or yeast cell wall particles are naturally enclosed vehicles with an interior cavity that can be exploited to carry and deliver drug payloads. The biological activities and targeting capacities of glucans depend largely on the recognition of glucan moieties by receptors such as dectin-1 and complement receptor 3, which are widely expressed on the cell membranes of mononuclear phagocytes, dendritic cells, neutrophils, and some lymphocytes. This review summarizes the chemical structures, sources, fundamental properties, extraction methods, and applications of these materials, with an emphasis on drug delivery. Glucans are utilized mainly as vaccine adjuvants, targeting ligands and as carrier materials for various drug entities. It is believed that glucans and glucan microparticles may be useful for the delivery of both small-molecule and macromolecular drugs, especially for potential treatment of immune-related diseases.

Effects of Cold Plasma Pretreatment on the Synthesis of Polysaccharide from Pleurotus ostreatus

Fungal polysaccharides have attracted wide attention because of their medical pharmaceutical and health care value. So far, many efforts have been made in strain improvement to produce polysaccharides on a large scale at low cost. Here, a novel cold plasma-induced strain improvement technology was employed to pretreat Pleurotus ostreatus CGMCC 5.374 by radio-frequency (RF) low-vacuum cold plasma (LVCP) for the purpose of obtaining a high-yield polysaccharide strain. The optimum pretreatment conditions including discharge power, treatment time, and working pressure were determined by single factor and orthogonal experiment in succession. Furthermore, transcriptome analysis was conducted to study the effects of RF-LVCP on cell metabolism and proliferation. Results showed that under the optimal condition of discharge power of 130 W, treatment time of 25 s and working pressure of 140 Pa, polysaccharide content in mycelium was increased by 3.16% after 6 days in comparison to the original strain. Transcriptome analysis showed that RF-LVCP is helpful for specific gene transcription profiles, Gene Ontology (GO) and KEGG pathways, of which the differentially expressed genes (DEGs) were mainly involve with the up-regulation of polysaccharide transport, physiology, synthesis and metabolism, as well as the down-regulation of polysaccharide hydrolysis and macromolecular degradation.

The function and application of edible fungal polysaccharides

Edible fungi, commonly known as mushrooms, are precious medicinal and edible homologous gifts from nature to us. Edible fungal polysaccharides (EFPs) are a variety of bioactive macromolecular which isolated from fruiting bodies, mycelia or fermentation broths of edible or medicinal fungus. Increasing researches have confirmed that EFPs possess multiple biological activities both in vitro and in vivo settings, including antioxidant, antiviral, anti-inflammatory, immunomodulatory, anti-tumor, hypoglycemic, hypolipidemic, and regulating intestinal flora activities. As a result, they have emerged as a prominent focus in the healthcare, pharmaceutical, and cosmetic industries. Fungal EFPs have safe, non-toxic, biodegradable, and biocompatible properties with low immunogenicity, bioadhesion ability, and antibacterial activities, presenting diverse potential applications in the food industries, cosmetic, biomedical, packaging, and new materials. Moreover, varying raw materials, extraction, purification, chemical modification methods, and culture conditions can result in variances in the structure and biological activities of EFPs. The purpose of this review is to provide comprehensively and systematically organized information on the structure, modification, biological activities, and potential applications of EFPs to support their therapeutic effects and health functions. This review provides new insights and a theoretical basis for prospective investigations and advancements in EFPs in fields such as medicine, food, and new materials.

Separation of anti-TMV active components and modes of action of Omphalia lapidescens

BACKGROUND

Omphalia lapidescens is a saprophytic and parasitic fungus belonging to the Polypora genus of Tricholomataceae. It has repellent, insecticidal, anti-inflammatory and immunomodulatory effects.

RESULT

This study found that the extract of O. lapidescens had significant anti-TMV activity, and the main active component was homopolysaccharide LW-1 by Bioassay-guided fractionation. LW-1 is a glucan with β-(1,3) glucoside bond as the main chain and β-(1,6) glucoside bond as the branch chain, with molecular weight in the range of 172,916-338,827 Da. The protective and inactive efficacies of LW-1(100 mg/L) against TMV were 78.10% and 48.20%, but had no direct effect on the morphology of TMV particles. The results of mechanism of action showed that LW-1 induced the increase of the activity of defense enzymes such as POD, SOD and PAL in Nicotiana glutinosa. The overexpression of resistance genes such as NPR1, PR1 and PR5, and the increase of SA content. Further transcriptome sequencing showed that LW-1 activated MAPK signaling pathway, plant-pathogen interaction pathway and glucosinolide metabolic pathway in Arabidopsis thaliana. Besides, LW-1 induced crops resistance against plant pathogenic fungi.

CONCLUSION

Taken together, the anti-TMV mechanism of LW-1 was to activate MAPK signaling pathway, inducing overexpression of resistance genes, activating plant immune system, and improving the synthesis and accumulation of plant defencins such as glucosinolide. LW-1-induced plant disease resistance has the advantages of broad spectrum and long duration, which has the potential to be developed as a new antiviral agent or plant immune resistance inducer.

Synergistic mediating effect of edible fungal polysaccharides (Auricularia and Tremellan) and Crataegus flavonoids in hyperlipidemic rats

Both edible fungal polysaccharides (Auricularia and Tremellan) and Crataegus flavonoids promote the balance of dyslipidemia, which have a positive biological regulating effect on intestinal flora. In this study, the extraction of water-soluble polysaccharides from Auricularia and Tremellan was investigated and optimized firstly. Polysaccharides and flavonoids were then combined to study the effects on the mediating role of abnormal blood lipid concentration and intestinal flora in vivo. The rats were divided into 10 groups, the NC (normal control), HM (model), PCI (Simvastatin control), PCII (Fenofibrate control), AAP (Auricularia auricular Polysaccharide), TFP (Tremella fuciformis Polysaccharide), HF (Crataegus Flavonoid), LDC (Low-dose combination), MDC (Medium dose combination), and HDC (High-dose combination), used to explore the impact of polysaccharides and flavonoids complex on state of blood lipid, liver, and intestinal flora of dyslipidemia rats. The results showed that the combination of polysaccharides and flavonoids could significantly decrease the levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and increase the level of high-density lipoprotein cholesterol (HDL-C). It also significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and improved liver morphology. What is more, the HDC favorably alters the intestinal microflora balance, promotes intestinal integrity and mobility, and inhibits the growth of harmful bacteria such as Escherichia coli/Shigella and Clostridium compared with HM group. In brief, the combination of polysaccharides and flavonoids had a synergistic effect on the remission of dyslipidemia, and promoted health by improving lipid metabolism, protecting liver tissue, and regulating the intestinal flora in hyperlipidemia rats.

Pharmacological mechanism of natural drugs and their active ingredients in the treatment of arrhythmia via calcium channel regulation

Arrhythmia is characterized by abnormal heartbeat rhythms and frequencies caused by heart pacing and conduction dysfunction. Arrhythmia is the leading cause of death in patients with cardiovascular disease, with high morbidity and mortality rates, posing a serious risk to human health. Natural drugs and their active ingredients, such as matrine(MAT), tetrandrine(TET), dehydroevodiamine, tanshinone IIA, and ginsenosides, have been widely used for the treatment of atrial fibrillation, ventricular ectopic beats, sick sinus syndrome, and other arrhythmia-like diseases owing to their unique advantages. This review summarizes the mechanism of action of natural drugs and their active ingredients in the treatment of arrhythmia via the regulation of Ca²⁺, such as alkaloids, quinones, saponins, terpenoids, flavonoids, polyphenols, and lignan compounds, to provide ideas for the innovative development of natural drugs with potential antiarrhythmic efficacy.

Microanalysis Characterization and Immunomodulatory Effect for Selenium-Enriched Polysaccharide from Morchella esculenta (L.) Pers

Morchella esculenta (L.) Pers., referred to as Morel, is a medicinal and edible homologous fungus, which contains many bioactive substances. In Morel, polysaccharides are the most abundant and have various bioactivities. In the present work, two novel polysaccharides, Se-MPS and MPS, were prepared and purified from selenium-enriched (Se-enriched) and common Morel mycelia, respectively, and their structural and immunomodulatory properties were evaluated. The results show that Se-enriched treatment significantly changed the polysaccharides' chemical composition, molecular weight, and sugar chain configuration. In addition, the Se-enriched treatment also improved the polysaccharides' fragmentation and thermal stability. Importantly, Se-enriched Morel polysaccharide (Se-MPS) could significantly enhance phagocytosis of RAW 264.7 macrophage cells and, remarkably, activate their immune response via activating the TLR4-TRAF6-MAPKs-NF-κB cascade signaling pathway, finally exerting an immunomodulatory function. Based on these findings, selenium-enriched Morel polysaccharide appears to have more potential for development and utilization in functional foods or medicines than ordinary Morel polysaccharide.

New Inonotus Polysaccharides: Characterization and Anticomplementary Activity of Inonotus rheades Mycelium Polymers

Inonotus is a small genus of xylotrophic basidiomycetes and a source of bioactive fungochemicals among which a special place is occupied by polymeric compounds. In this study, polysaccharides that are widespread in Europe, Asia, and North America and a poorly understood fungal species, I. rheades (Pers.) Karst. (fox polypore), were investigated. Water-soluble polysaccharides of I. rheades mycelium were extracted, purified, and studied using chemical reactions, elemental and monosaccharide analysis, UV-Vis and FTIR spectroscopy, gel permeation chromatography, and linkage analysis. Five homogenic polymers (IRP-1-IRP-5) with molecular weights of 110-1520 kDa were heteropolysaccharides that consist mainly of galactose, glucose, and mannose. The dominant component, IRP-4, was preliminary concluded to be a branched (1→3,6)-linked galactan. Polysaccharides of I. rheades inhibited the hemolysis of sensitized sheep erythrocytes by complement from human serum, signifying anticomplementary activity with the greatest effects for the IRP-4 polymer. These findings suggest that I. rheades mycelium is a new source of fungal polysaccharides with potential immunomodulatory and anti-inflammatory properties.

The Mushroom Glucans: Molecules of High Biological and Medicinal Importance

Carbohydrates, including polysaccharide macromolecules, are the main constituents of the fungal cell wall. Among these, the homo- or heteropolymeric glucan molecules are decisive, as they not only protect fungal cells but also have broad, positive biological effects on the animal and human bodies. In addition to the beneficial nutritional properties of mushrooms (mineral elements, favorable proteins, low fat and energy content, pleasant aroma, and flavor), they have a high glucan content. Folk medicine (especially in the Far East) used medicinal mushrooms based on previous experience. At the end of the 19th century, but mainly since the middle of the 20th century, progressively more scientific information has been published. Glucans from mushrooms are polysaccharides that contain sugar chains, sometimes of only one kind (glucose), sometimes having several monosaccharide units, and they have two (α and β) anomeric forms (isomers). Their molecular weights range from 10⁴ to 10⁵ Da, and rarely 10⁶ Da. X-ray diffraction studies were the first to determine the triple helix configuration of some glucans. It seems that the existence and integrity of the triple helix structure are criteria for their biological effects. Different glucans can be isolated from different mushroom species, and several glucan fractions can be obtained. The biosynthesis of glucans takes place in the cytoplasm, the processes of initiation and then chain extension take place with the help of the glucan synthase enzyme complex (EC 2.4.1.34), and the sugar units are provided by sugar donor UDPG molecules. The two methods used today for glucan determination are the enzymatic and Congo red methods. True comparisons can only be made using the same method. Congo red dye reacts with the tertiary triple helix structure, and the resulting glucan content better reflects the biological value of glucan molecules. The biological effect of β-glucan molecules is proportional to the integrity of the tertiary structure. The glucan contents of the stipe exceed the values of the caps. The glucan levels of individual fungal taxa (including varieties) differ quantitatively and qualitatively. This review presents in more detail the glucans of lentinan (from Lentinula edodes), pleuran (from Pleurotus ostreatus), grifolan (from Grifola frondose), schizophyllan (from Schizophyllum commune), and krestin (from Trametes versicolor), along with their main biological effects.

Antifungal Activity of Medicinal Mushrooms and Optimization of Submerged Culture Conditions for Schizophyllum commune (Agaricomycetes)

The main goal of the present study was the exploration of the antifungal properties of Agaricomycetes mushrooms. Among twenty-three tested mushrooms against A. niger, B. cinerea, F. oxysporum, and G. bidwellii, Schizophyllum commune demonstrated highest inhibition rates and showed 35.7%, 6.5%, 50.4%, and 66.0% of growth inhibition, respectively. To reveal culture conditions enhancing the antifungal potential of Sch. commune, several carbon (lignocellulosic substrates among them) and nitrogen sources and their optimal concentrations were investigated. Presence of 6% mandarin juice production waste (MJPW) and 6% of peptone in nutrient medium promoted antifungal activity of selected mushroom. It was determined that, extracts obtained in the presence of MJPW effectively inhibited the grow of pathogenic fungi. Moreover, the content of phenolic compounds in the extracts obtained from Sch. commune grown on MJPW was several times higher (0.87 ± 0.05 GAE/g to 2.38 ± 0.08 GAE/g) than the extracts obtained from the mushroom grown on the synthetic (glycerol contained) nutrient medium (0.21 ± 0.03 GAE/g to 0.88 ± 0.05 GAE/g). Flavonoid contents in the extracts from Sch. commune varied from 0.58 ± 0.03 to 27.2 ± 0.8 mg QE/g. Identification of phenolic compounds composition in water and ethanol extracts were provided by mass spectrometry analysis. Extracts demonstrate considerable free radical scavenging activities and the IC50 values were generally low for the extracts, ranging from 1.9 mg/ml to 6.7 mg/ml. All the samples displayed a positive correlation between their concentration (0.05-15.0 mg/ml) and DPPH radical scavenging activity. This investigation revealed that Sch. commune mushroom has great potential to be used as a source of antifungal and antioxidant substances.