Chemical structures, extraction and analysis technologies, and bioactivities of edible fungal polysaccharides from Poria cocos: An updated review

Poria cocos is a popular medicinal food. Polysaccharides are the key component of Poria cocos, forming 70-90 % of the dry sclerotia mass. Recent studies indicate that Poria cocos polysaccharides (PCP-Cs) have multiple beneficial functions and applications. A literature search was conducted using the Web of Science Core Collection and PubMed databases. For this review, we provided an updated research progress in chemical structures, various extraction and analysis technologies, bioactivities of PCP-Cs, and insights into the directions for future research. The main polysaccharides identified in Poria cocos are water-soluble polysaccharides and acidic polysaccharides. Hot water, alkali, supercritical fluid, ultrasonic, enzyme, and deep eutectic solvent-based methods are the most common methods for PCP-Cs extraction. Technologies such as near-infrared spectroscopy, high-performance liquid chromatography, and ultraviolet-visible spectrophotometry, are commonly used to evaluate the qualities of PCP-Cs. In addition, PCP-Cs have antioxidant, immunomodulatory, neuroregulatory, anticancer, hepatoprotective, and gut microbiota regulatory properties. Future research is needed to focus on scaling up extraction, enhancing quality control, elucidating mechanisms of bioactivities, and the utilisation of PCP-Cs in food industries. Overall, Poria cocos is a good source of edible fungi polysaccharides, which can be developed into functional foods with potential health benefits.

Structural characterization and immunomodulatory activity of a water-soluble polysaccharide from Poria cocos

In order to investigate the structural characteristics and immunomodulatory effects of Poria cocos polysaccharides, a water-soluble homogeneous polysaccharide (PCP-2) was isolated by water extraction and alcohol precipitation and further purified by Cellulose DEAE-52 and Sephacryl S-100HR column chromatography. PCP-2 is a heteropolysaccharide composed of glucose, galactose, mannose, and fucose in a molar ratio of 42.0: 35.0: 13.9: 9.1. It exhibits a narrow molecular weight distribution at 2.35 kDa with a branching degree of 37.1 %. The main chain types of PCP-2 include 1,3-β-D-Glc and 1,6-β-D-Glc as the backbone glucans and 1,6-α-D-Gal as the backbone heterogalactan. In vitro experiments demonstrate that PCP-2 directly stimulate RAW264.7 cell proliferation and secretion of inflammatory factors such as NO and TNF-α. In cyclophosphamide (CTX)-induced mice, it promotes the development of thymus and spleen immune organs, elevates the blood levels of IgG, IgA, IgM and CD3+CD4+ T cells, increases the intestinal villus height/ crypt depth ratio and improves gut barrier dysfunctions. These findings suggest that PCP-2 is a natural fungal polysaccharide with broad spectrum of immunoenhancing effects, which can significantly ameliorate the immunocompromised state.

Grifola frondosa polysaccharides: A review on structure/activity, biosynthesis and engineering strategies

Polysaccharides are the main polymers in edible fungi Grifola frondosa, playing a crucial role in the physiology and representing the healthy benefits for humans. Recent efforts have well elucidated the fine structures and biological functions of G. frondosa polysaccharides. The recently-rapid developments and increasing availability in fungal genomes also accelerated the better understanding of key genes and pathways involved in biosynthesis of G. frondosa polysaccharides. Herein, we provide a brief overview of G. frondosa polysaccharides and their activities, and comprehensively outline the complex process, genes and proteins corresponding to G. frondosa polysaccharide biosynthesis. The regulation strategies including strain improvement, process optimization and genetic engineering were also summarized for maximum production of G. frondosa polysaccharides. Some remaining unanswered questions in describing the fine synthesis machinery were also pointed out to open up new avenues for answering the structure-activity relationship and improving polysaccharide biosynthesis in G. frondosa. The review hopefully presents a reasonable full picture of activities, biosynthesis, and production regulation of polysaccharide in G. frondosa.

Identification and Quantification of Monosaccharides from Fungal Cell Walls and Exopolysaccharides by Gas Chromatography Coupled to Mass Spectrometry

The fungal cell wall and secreted exopolysaccharides play an important role in the interactions between fungi and their environment. Despite their central role in fungal biology, ecology, and host-pathogen interactions, the composition of these polymers and their synthetic pathways are not well understood. The protocols presented in this article describe an approach to isolate fungal cell wall polysaccharides and to identify and quantify the monosaccharide composition of these polymers by gas chromatography-mass spectrometry (GC-MS). © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: O-methyl trimethylsilyl monosaccharide derivatives composition analysis by GC-MS Support Protocol: Fungal cell wall extraction.

Bovine lactoferrin and Lentinus edodes mycelia polysaccharide complex: The formation and the activity to protect islet β cells

The formation of complexes may be used for the development of delivery systems in foods field. The aim of this study was to explore the interaction mechanism between Lentinus edodes mycelia polysaccharide (LMP) and bovine lactoferrin (BLF), and the activity of LMP-BLF complex to inhibit oxidative stress in islet β cells. The interaction mechanisms of LMP with BLF were investigated with multi-spectroscopic techniques. The multi-spectroscopic analysis result showed that LMP bound with BLF by van der Waals force and hydrogen bond. The quenching mechanism of BLF with LMP was static quenching. Cell viability, reactive oxygen species (ROS) level, apoptosis and the related signaling pathways were detected with thiazolyl blue tetrazolium bromide (MTT) assay, 2,7-Dichlorofluorescin diacetate (DCFH-DA) staining, Hoechst 33258 staining and Western blot methods respectively. The complex alleviated apoptosis induced by hydrogen peroxide (H₂O₂), and inhibited oxidative stress via MAPK pathways in MIN6 cells. In addition, the complex was able to promote glucose uptake in HepG2 cells. These results will broaden our understanding of LMP-BLF complexes and the applications of polysaccharide-protein complexes in the foods field.

Characteristics and antifatigue activity of graded polysaccharides from Ganoderma lucidum separated by cascade membrane technology

In this paper, cascade membrane technology was utilized to classify polysaccharides from Ganoderma lucidum (GLPs). The properties and antifatigue activity of graded polysaccharides were identified and compared. GLPs were separated using cascade ultrafiltration membranes of 100 kDa, 10 kDa and 1 kDa in sequence. The molecular weights of polysaccharides in these GLP fractions were approximately 322.0 kDa, 18.8 kDa and 6.4 kDa, and all polysaccharides were in active β-configurations. This showed that all graded GLPs could elongate swimming time, improve endurance and promote fatigue recovery, especially polysaccharides with molecular weights above 10 kDa. This demonstrated that GLPs could decrease the activities of SUN and CK and the levels of MDA and BLA. They also increased the level of Gly, accelerated fat transformation, and improved the activities of GPx, SOD and LDH in all treated mice. Accordingly, GLPs above 10 kDa might be potential agents with antifatigue activity.

Fabrication and characterization of Rhizochitosan and its incorporation with platelet concentrates to promote wound healing

Composite dressing composed of Rhizochitosan and Regenplex™ to promote wound healing were assessed. Rhizochitosan was fabricated by deacetylation of Rhizochitin, which obtained by simply depigmenting sporangium-free mycelial mattress produced from Rhizopus stolonifer F6. Physicochemical characterizations of Rhizochitosan demonstrated that it contained 13.5% chitosan with a water-absorption ability of 35-fold dry weight and exhibiting hydrogel nature after hydration. In a wound-healing study on SD rats with full-thickness injury, the composite dressing had a better healing effect than those for each individual components and control group and wound even healed as functional tissue instead of scar tissue. The underlying mechanism of the composite beneficial to wound remodeling is likely attributable to a more reduction level of matrix metalloproteinase (MMP)-9 expression in early stage and a higher MMP-2 expression level in a later stage of healing process. Conclusively, the composite dressing demonstrated to be highly beneficial to the healing of full-thickness injury wound.

Yeast Shells Encapsulating Adjuvant AS04 as an Antigen Delivery System for a Novel Vaccine against Toxoplasma Gondii

Toxoplasma gondii (T. gondii) infection causes severe zoonotic toxoplasmosis, which threatens the safety of almost one-third of the human population globally. However, there is no effective protective vaccine against human toxoplasmosis. This necessitates anti-T. gondii vaccine development, which is a main priority of public health. In this study, we optimized the adjuvant system 04 (AS04), a vaccine adjuvant constituted by 3-O-desacyl-4'-monophosphoryl lipid A (a TLR4 agonist) and aluminum salts, by packing it within natural extracts of β-glucan particles (GPs) from Saccharomyces cerevisiae to form a GP-AS04 hybrid adjuvant system. Through a simple mixing procedure, we loaded GP-AS04 particles with the total extract (TE) of T. gondii lysate, forming a novel anti-T. gondii vaccine GP-AS04-TE. Results indicated that the hybrid adjuvant can efficiently and stably load antigens, mediate antigen delivery, facilitate the dendritic uptake of antigens, boost dendritic cell maturation and stimulation, and increase the secretion of pro-inflammatory cytokines. In the mouse inoculation model, GP-AS04-TE significantly stimulated the function of dendritic cells, induced a very strong TE-specific humoral and cellular immune response, and finally showed a strong and effective protection against toxoplasma chronic and acute infections. This work proves the potential of GP-AS04 for exploitation as a vaccine against a range of pathogens.

Construction of hydrogels based on the homogeneous carboxymethylated chitin from Hericium erinaceus residue: Role of carboxymethylation degree

Carboxymethyl chitin hydrogels with different degree of substitution (DS) were prepared by the homogeneous carboxymethylation of chitin extracted from Hericium erinaceus residue. The effect of DS on gel structure and property were studied. Results showed that the DS of carboxymethyl chitin hydrogels can be increased by increasing the amount of sodium chloroacetate. The equilibrium swelling degree and pH swelling sensitivity of the hydrogels were enhanced as the increase of DS. Zeta potential, low-field nuclear magnetic resonance, contact angle and molecular dynamics simulation results suggested that the introduction of carboxymethyl functional group enhanced the negative charge, water mobility, surface hydrophilicity and the ability to form hydrogen bonds with water of the hydrogels, resulting in an increased swelling degree of the hydrogels. Moreover, the prepared hydrogels showed different adsorption capability to various dyes, and the adsorption performance of the prepared hydrogels for cationic dyes could be enhanced as the increase of DS.

Immunomodulating Effects of Fungal Beta-Glucans: From Traditional Use to Medicine

The importance of a well-functioning and balanced immune system has become more apparent in recent decades. Various elements have however not yet been uncovered as shown, for example, in the uncertainty on immune system responses to COVID-19. Fungal beta-glucans are bioactive molecules with immunomodulating properties. Insights into the effects and function of beta-glucans, which have been used in traditional Chinese medicine for centuries, advances with the help of modern immunological and biotechnological methods. However, it is still unclear into which area beta-glucans fit best: supplements or medicine? This review has highlighted the potential application of fungal beta-glucans in nutrition and medicine, reviewing their formulation, efficacy, safety profile, and immunomodulating effects. The current status of dietary fungal glucans with respect to the European scientific requirements for health claims related to the immune system and defense against pathogens has been reviewed. Comparing the evidence base of the putative health effects of fungal beta-glucan supplements with the published guidance documents by EFSA on substantiating immune stimulation and pathogen defense by food products shows that fungal beta-glucans could play a role in supporting and maintaining health and, thus, can be seen as a good health-promoting substance from food, which could mean that this effect may also be claimed if approved. In addition to these developments related to food uses of beta-glucan-containing supplements, beta-glucans could also hold a novel position in Western medicine as the concept of trained immunity is relatively new and has not been investigated to a large extent. These innovative concepts, together with the emerging success of modern immunological and biotechnological methods, suggest that fungal glucans may play a promising role in both perspectives, and that there are possibilities for traditional medicine to provide an immunological application in both medicine and nutrition.

Production, purification, characterization, and biological properties of Rhodosporidium paludigenum polysaccharide

The yield of marine red yeast polysaccharide (MRYP) obtained from Rhodosporidium paludigenum was increased by optimizing fermentation conditions, and the pure polysaccharide was extracted by column chromatography. The molecular weight of pure MRYP and the ratio of mannose to glucose in components of MRYP were determined. Antioxidant and antibacterial abilities of MRYP were investigated in vitro and in vivo. The optimal fermentation parameters were as follows: Medium 4, pH = 6.72, temperature = 30.18°C, blades speed = 461.36 r/min; the optimized yield reached 4323.90 mg/L, which was 1.31 times the original yield. The sequence of factors that affected the MRYP yield was the blades speed>pH>temperature. The main components of MRYP were MYH-1 and MYH-2. The molecular weights of MYH-1 and MYH-2 were 246.92 kDa and 21.88 kDa, respectively; they accounted for 53.60% and 28.75% of total polysaccharide. In MYH-1 and MYH-2, the proportion of glucose and mannose accounted for 46.94%, 38.46%, and 67.10%, 7.17%, respectively. In vitro, the ability of scavenging DPPH•, •OH, and •O2− radical was 32.26%, 24.34%, and 22.09%; the minimum inhibitory concentration (MIC) of MRYP was 480 μg/mg. In vivo, MRYP improved the lambs’ body weight, antioxidant enzyme activity, and the number of probiotics, but it reduced the feed/gain (F/G) ratio and the number of pathogenic bacteria in 60-days-old lambs.

Poria cocos polysaccharide induced Th1-type immune responses to ovalbumin in mice

In the present study, we evaluated adjuvant potential of Poria cocos polysaccharide (PCP) on the Th1-type immune responses of C57/BL6 mice against ovalbumin (OVA). We first determined the effect of PCP on maturation of murine bone marrow derived dendritic cells (BMDCs), PCP significantly upregulated surface expression of MHCII, CD40, CD80, CD86 and enhanced production of IL-6 and IL-12p40. In addition, PCP affected receptor-mediated endocytosis, but not pinocytosis in BMDCs. Furthermore, OVA + PCP immunization induced specific cytotoxic CD8⁺ T cell killing of OVA (257–264) peptide pulsed cell. When mice were immunized subcutaneously in a week interval with OVA + PCP. Serum were collected for measuring OVA-specific antibody and splenocytes were harvested for analyzing CD69, IFN-γ ELISpot and cytokines production. The result indicated that OVA-specific IgG, IgG2a and IgG1 antibody levels in serum were significantly elevated by PCP compared with control. PCP increased OVA-specific IFN-γ-secreting CD8⁺, CD4⁺ T cells, promoted CD8⁺ T cell proliferation and up-regulated Th-1 type (IFN-γ, IL-2) cytokine production. In conclusion, data suggest that PCP enhanced cellular immune response and possess potential as a vaccine adjuvant for Th1 immune response.

Medicinal Properties and Bioactive Compounds from Wild Mushrooms Native to North America

Mushrooms, the fruiting bodies of fungi, are known for a long time in different cultures around the world to possess medicinal properties and are used to treat various human diseases. Mushrooms that are parts of traditional medicine in Asia had been extensively studied and this has led to identification of their bioactive ingredients. North America, while home to one of the world's largest and diverse ecological systems, has not subjected its natural resources especially its diverse array of mushroom species for bioprospecting purposes: Are mushrooms native to North America a good source for drug discovery? In this review, we compile all the published studies up to September 2020 on the bioprospecting of North American mushrooms. Out of the 79 species that have been investigated for medicinal properties, 48 species (60%) have bioactivities that have not been previously reported. For a mere 16 selected species, 17 new bioactive compounds (10 small molecules, six polysaccharides and one protein) have already been isolated. The results from our literature search suggest that mushrooms native to North America are indeed a good source for drug discovery.

Structural characterization of enzymatic modification of Hericium erinaceus polysaccharide and its immune-enhancement activity

In this study, the enzyme degradation of Hericium erinaceus polysaccharide (HEP) was successfully modified with endo-rhamnosidase to obtain the enzymatic hydrolysis of Hericium erinaceus polysaccharide product (EHEP). The gas chromatography-mass spectrometry (GC-MS), high performance gel permeation chromatography (HPGPC), Fourier transformed infrared spectrometry (FT-IR), scanning electron microscopy (SEM), atomic particle microscopy (AFM), nuclear magnetic resonance (NMR) and particle size distribution were used to characterize polysaccharides. In vitro, EHEP significantly enhanced the phagocytosis, NO, CD40 and CD86 by macrophage than HEP. In vivo, female Balb/c mice were injected respectively with EHEP and HEP after administrated with cyclophosphamide, once a day for 7 days. On days 11, the morphology and structure of jejunal sections, immunofluorescence of spleen and peritoneal macrophages were determined. These results indicated that the enzymatic hydrolysis product could enhance the activation of peritoneal macrophages, and enhance the immunomodulation function of HEP. This study demonstrated that enzymatic modification was an effective method to improve the activities of HEP, and could be developed as a potential technology for use in pharmaceutical and cosmeceutical industry.

Occurrence and possible roles of polysaccharides in fungi and their influence on the development of new technologies

The article summarizes the roles of polysaccharides in the biology of fungi and their relationship in the development of new technologies. The comparative approach between the evolution of fungi and the chemistry of glycobiology elucidated relevant aspects about the role of polysaccharides in fungi. Also, based on the knowledge of fungal glycobiology, it was possible to address the development of new technologies, such as the production of new anti-tumor drugs, vaccines, biomaterials, and applications in the field of robotics. We conclude that polysaccharides activate pathways of apoptosis, secretion of pro-inflammatory substances, and macrophage, inducing anticancer activity. Also, the activation of the immune system, which opens the way for the production of vaccines. The development of biomaterials and parts for robotics is a promising and little-explored field. Finally, the article is multidisciplinary, with a different and integrated approach to the role of nature in the sustainable development of new technologies.

Comparison of the Partial Structure and Antioxidant Activity of Polysaccharides from Two Species of Chinese Truffles

Truffles are world-renowned premium commodities. Due to their unique aroma and rarity, the price of truffles has always been very high. In this study, Diethylaminoethyl anion exchange chromatography and gel filtration were employed for polysaccharide purification from two different species of Chinese truffles. Three polysaccharide fractions were obtained from Tuber panzhihuanense and referred to as TPZ-NP, TPZ-I, and TPZ-II. Additionally, two polysaccharide fractions were purified from T. pseudoexcavatum (TPD-NP and TPD-I). The results of structural elucidation indicated that the polysaccharide from different species showed different monosaccharide composition and linkage units, as well as molecular weight. Two of the polysaccharide fractions with the highest yield, TPZ-I and TPD-I, were chosen for biological testing. The results indicated that both fractions displayed antioxidant properties through mediation of the intestinal cellular antioxidant defense system, which could protect cultured intestinal cells from oxidative stress-induced damage and cell viability suppression. The TPD-I fraction showed stronger antioxidant effects, which may be due to the difference in structure. Further study on the structure-activity relationship is needed to be done.

Immunomodulatory and Antioxidant Effects of Polysaccharides from the Parasitic Fungus Cordyceps kyushuensis

The ascomycete Cordyceps genus has been used as valued traditional Chinese medicine. Cordyceps kyushuensis is a unique species of Cordyceps, which parasitizes on the larvae of Clanis bilineata Walker, and its major component cordycepin and aqueous extract are known to have many pharmacological effects. However, the physiological function of water-soluble polysaccharides has not been explored in detail. In this study, to resolve these doubts, we extracted and separated Cordyceps-derived polysaccharides and then evaluated the immunomodulatory and antioxidant activities. Four polysaccharide fractions were purified from Cordyceps-cultured stroma by DEAE-cellulose 23 and Sephadex G-150 column chromatography. Basic structural information was elucidated on the basis of physicochemical property and spectroscopic evidences. The antioxidant activities were evaluated by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method and protective effect of DNA damage. The qualified immunologic activities were also determined in vivo and in vitro. The polysaccharides could stimulate the proliferation of mouse splenocytes whether concanavalin A (ConA) and lipopolysaccharide (LPS) existed or not, strengthen peritoneal macrophages to devour neutral red, and increase the content of interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-α) in serum. The research provides the corresponding evidence for Cordyceps polysaccharides as a potential candidate for functional foods and therapeutic agents.

The Structural Characteristics and Biological Activities of Intracellular Polysaccharide Derived from Mutagenic Sanghuangporous sanghuang Strain

Sanghuangporous sanghuang is a rare medicinal fungus which contains polysaccharide as the main active substance and was used to treat gynecological diseases in ancient China. The intracellular polysaccharide yield of S. sanghuang was enhanced by the strain A130 which was screened from mutant strains via atmospheric and room temperature plasma (ARTP) mutagenesis. The objective of this research was to investigate the effects of ARTP mutagenesis on structural characteristics and biological activities of intracellular polysaccharides from S. sanghuang. Six intracellular polysaccharide components were obtained from S. sanghuang mycelia cultivated by the mutagenic strain (A130) and original strain (SH1), respectively. The results revealed that the yields of polysaccharide fractions A130-20, A130-50 and A130-70 isolated from the mutagenic strain fermentation mycelia were significantly higher than those of the original ones by 1.5-, 1.3- and 1.2-fold, and the clear physicochemical differences were found in polysaccharide fractions precipitated by 20% ethanol. A130-20 showed a relatively expanded branching chain with higher molecular weight and better in vitro macrophage activation activities and the IL-6, IL-1, and TNF-α production activities of macrophages were improved by stimulation of A130-20 from the mutagenic strain. This study demonstrates that ARTP is a novel and powerful tool to breed a high polysaccharide yield strain of S. sanghuang and may, therefore, contribute to the large-scale utilization of rare medicinal fungi.

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.

Structural characterization of phosphorylated Pleurotus ostreatus polysaccharide and its hepatoprotective effect on carbon tetrachloride-induced liver injury in mice

This study aimed to explore the basic structural features of phosphorylated Pleurotus ostreatus polysaccharide (PPOP) and study the protective effect of PPOP on liver injury induced by carbon tetrachloride in male Kunming mice. The phosphorylated polysaccharide was prepared from the natural polysaccharide extracted from Pleurotus ostreatus (POP). The structures of PPOP and POP were characterized by FT-IR, ESEM spectroscopy, and Congo red test. Chemical composition analysis revealed that PPOP was mainly composed of rhamnose, galacturonic acid, and xylose in a molar ratio of 0.10: 1.98: 1.00. Structural analysis indicated that PPOP had multi-strand structure and the absorption peaks of PO and P-O-C. Furthermore, animal experiments showed that the hepatoprotective effect of PPOP against liver injury was reflected by decreasing the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total cholesterol, trilaurin, and low-density lipoprotein cholesterol in the serum, increasing the content of high-density lipoprotein cholesterol and albumin in blood, reducing the content of malondialdehyde and promoting the activity of antioxidant enzymes in liver. PPOP exhibited stronger hepatoprotective effect and antioxidant activity in vivo than POP. The final results indicated that PPOP could be used in the treatment of chemical-induced hepatotoxicity based on the above biological research.

Distribution of Zinc in Mycelial Cells and Antioxidant and Anti-Inflammatory Activities of Mycelia Zinc Polysaccharides from Thelephora ganbajun TG-01

This study demonstrates that Thelephora ganbajun had a strong ability to absorb zinc, and zinc can be compartmentally stored in the small vesicles and mainly accumulated in the form of zinc-enriched polysaccharides (zinc content was 25.0 ± 1.27 mg/g). Mycelia zinc polysaccharides (MZPS) and its fractions were isolated. The main fraction (MZPS-2) with the highest antioxidant activity in vitro was composed of mannose : galacturonic acid : glucose : galactose in a molar ratio of 61.19 : 1 : 39.67 : 48.67, with a weight-averaged molecular weight of 5.118 × 105 Da. MZPS-2 had both α-pyranose and β-pyranose configuration and had a triple helical conformation. By establishing zebrafish models, we found that MZPS-2 can significantly scavenge free radicals, reduce the generation of reactive oxygen species caused by inflammation, and inhibit the recruitment of neutrophils toward the injury site. Therefore, MZPS-2 exhibited antioxidant and anti-inflammatory effects and can be used as a zinc supplement with specific biological activities to alleviate zinc deficiency complications, such as chronic oxidative stress or inflammation.

Development of a novel β-1,6-glucan-specific detection system using functionally-modified recombinant endo-β-1,6-glucanase

β-1,3-d-Glucan is a ubiquitous glucose polymer produced by plants, bacteria, and most fungi. It has been used as a diagnostic tool in patients with invasive mycoses via a highly-sensitive reagent consisting of the blood coagulation system of horseshoe crab. However, no method is currently available for measuring β-1,6-glucan, another primary β-glucan structure of fungal polysaccharides. Herein, we describe the development of an economical and highly-sensitive and specific assay for β-1,6-glucan using a modified recombinant endo-β-1,6-glucanase having diminished glucan hydrolase activity. The purified β-1,6-glucanase derivative bound to the β-1,6-glucan pustulan with a KD of 16.4 nm We validated the specificity of this β-1,6-glucan probe by demonstrating its ability to detect cell wall β-1,6-glucan from both yeast and hyphal forms of the opportunistic fungal pathogen Candida albicans, without any detectable binding to glucan lacking the long β-1,6-glucan branch. We developed a sandwich ELISA-like assay with a low limit of quantification for pustulan (1.5 pg/ml), and we successfully employed this assay in the quantification of extracellular β-1,6-glucan released by >250 patient-derived strains of different Candida species (including Candida auris) in culture supernatant in vitro We also used this assay to measure β-1,6-glucan in vivo in the serum and in several organs in a mouse model of systemic candidiasis. Our work describes a reliable method for β-1,6-glucan detection, which may prove useful for the diagnosis of invasive fungal infections.

Comparative Studies on Polysaccharides, Triterpenoids, and Essential Oil from Fermented Mycelia and Cultivated Sclerotium of a Medicinal and Edible Mushroom, Poria Cocos

Poria cocos, an important medicinal and edible fungus, is well known in East Asia. The main active components are water-soluble polysaccharides (WPS) and triterpenoids. Due to the growing market demand, long cultivation period, and consumption of pine trunk during cultivation, alternative methods for producing P. cocos or its active components should be investigated. In this study, WPS, triterpenoids, monosaccharide composition, and essential oil in fermented mycelia and cultivated sclerotium were analyzed using UV spectrophotometry, HPLC, pre-column derivatization, and HS-GC/MS, respectively. Our results showed that the WPS and triterpenoids in mycelia are several times higher than those in sclerotium. Among the 62 compounds identified by HS-GC/MS analysis from the essential oil obtained from the fermentation media and a fresh external layer, the two main fragrances in common were linalool and methyl phenylacetate. Our results suggested that it is applicable to produce polysaccharides and triterpenoids by the fermentation of P. cocos, and a strategy to improve triterpenoid production in the fermentation process was proposed.

Cordyceps militaris polysaccharide converts immunosuppressive macrophages into M1-like phenotype and activates T lymphocytes by inhibiting the PD-L1/PD-1 axis between TAMs and T lymphocytes

Tumour-associated macrophages (TAMs) inhibit the killing effect of T lymphocytes on tumour cells through the immunocheckpoint programmed death ligand-1 (PD-L1)/programmed death-1 (PD-1) axis. TAMs-targeted therapy is a promising approach that could be used to reverse the immunosuppressive tumour microenvironment. Here, we further report CMPB90-1, a novel natural polysaccharide from Cordyceps militaris, could function as an anti-tumour modulator that resets TAMs from a tumour-promoting M2 phenotype to a tumour-killing M1 phenotype. This process involves reversing the functional inhibition of T lymphocytes by inhibiting the PD-L1/PD-1 axis between TAMs and T lymphocytes. Mechanistically, the membrane receptor of CMPB90-1 binding to M2 macrophages was identified by tandem mass spectrometry. CMPB90-1 converts immunosuppressive TAMs via binding to toll-like receptor 2 (TLR2), which causes the release of Ca²⁺ and the activation of p38, Akt and NF-κB, or ERK. This process then leads to the polarization of TAMs from M2 phenotype to the M1 phenotype. In vivo experiment shows that CMPB90-1 is able to polarize TAMs into the M1 phenotype and has anti-tumour effects with improved safety. Additionally, the anti-tumour effects of CMPB90-1 in vivo depend on the phenotypic conversion of TAMs. The results demonstrated that CMPB90-1 could be developed as a potential immune-oncology treatment reagent.

Nutritional Mushroom Treatment in Meniere's Disease with Coriolus versicolor: A Rationale for Therapeutic Intervention in Neuroinflammation and Antineurodegeneration

Meniere's disease (MD) represents a clinical syndrome characterized by episodes of spontaneous vertigo, associated with fluctuating, low to medium frequencies sensorineural hearing loss (SNHL), tinnitus, and aural fullness affecting one or both ears. To date, the cause of MD remains substantially unknown, despite increasing evidence suggesting that oxidative stress and neuroinflammation may be central to the development of endolymphatic hydrops and consequent otholitic degeneration and displacement in the reuniting duct, thus originating the otolithic crisis from vestibular otolithic organs utricle or saccule. As a starting point to withstand pathological consequences, cellular pathways conferring protection against oxidative stress, such as vitagenes, are also induced, but at a level not sufficient to prevent full neuroprotection, which can be reinforced by exogenous nutritional approaches. One emerging strategy is supplementation with mushrooms. Mushroom preparations, used in traditional medicine for thousands of years, are endowed with various biological actions, including antioxidant, immunostimulatory, hepatoprotective, anticancer, as well as antiviral effects. For example, therapeutic polysaccharopeptides obtained from Coriolus versicolor are commercially well established. In this study, we examined the hypothesis that neurotoxic insult represents a critical primary mediator operating in MD pathogenesis, reflected by quantitative increases of markers of oxidative stress and cellular stress response in the peripheral blood of MD patients. We evaluated systemic oxidative stress and cellular stress response in MD patients in the absence and in the presence of treatment with a biomass preparation from Coriolus. Systemic oxidative stress was estimated by measuring, in plasma, protein carbonyls, hydroxynonenals (HNE), and ultraweak luminescence, as well as by lipidomics analysis of active biolipids, such as lipoxin A4 and F2-isoprostanes, whereas in lymphocytes we determined heat shock proteins 70 (Hsp72), heme oxygenase-1 (HO-1), thioredoxin (Trx), and γ-GC liase to evaluate the systemic cellular stress response. Increased levels of carbonyls, HNE, luminescence, and F2-isoprostanes were found in MD patients with respect to the MD plus Coriolus-treated group. This was paralleled by a significant (p < 0.01) induction, after Coriolus treatment, of vitagenes such as HO-1, Hsp70, Trx, sirtuin-1, and γ-GC liase in lymphocyte and by a significant (p < 0.05) increase in the plasma ratio-reduced glutathione (GSH) vs. oxidized glutathione (GSSG). In conclusion, patients affected by MD are under conditions of systemic oxidative stress, and the induction of vitagenes after mushroom supplementation indicates a maintained response to counteract intracellular pro-oxidant status. The present study also highlights the importance of investigating MD as a convenient model of cochlear neurodegenerative disease. Thus, searching innovative and more potent inducers of the vitagene system can allow the development of pharmacological strategies capable of enhancing the intrinsic reserve of vulnerable neurons, such as ganglion cells to maximize antidegenerative stress responses and thus providing neuroprotection.

Physicochemical properties and bioactivities of original and Se-enriched polysaccharides with different molecular weights extracted from Pleurotus ostreatus

Three polysaccharides (WZP1, WZP2, WZP3) and their Se-enriched products (SeWZP1, SeWZP2 and SeWZP3) were obtained from Pleurotus ostreatus using a simple, rapid method and HNO3-Na2SeO3 method, respectively. The molecular weight distribution profiles of all samples except SeWZP2 showed double peaks. The average molecular weights (Mw) of WZP1-3 were 48.6 kDa, 20.2 kDa and 11.8 kDa, respectively, and of SeWZP1-3 were 19.6 kDa, 37.7 kDa, 14.5 kDa, respectively. The complexity of monosaccharide composition of WZP1-3 was inversely proportional to the ethanol concentration used in the ethanol precipitation process. Additionally, the results of biological activity tests indicated that α-glucosidase inhibitory activity of WZP1-3 was related to the molecular weight and the monosaccharide composition complexity. The selenized modification can improve the α-glucosidase-inhibiting, hydroxyl radical-scavenging activity of P. ostreatus polysaccharides. Therefore, by improving their bioactivities by selenization, the polysaccharides of P. ostreatus could be utilized as a natural health food supplement.

Fungal polysaccharides

Fungal bioactive polysaccharides are well known and have been widely used in Asia as a part of the traditional diet and medicine. In fact, some biopolymers (mainly β-glucans or glycoconjugate) have already made their way to the market as antitumor or immunostimulating drugs. In the last decades, the relationship between structure and activity of polysaccharides and their detailed mode of action have been the core of intense research to understand and utilize their medicinal properties. Most of the antitumor polysaccharides belong to conserved β-glucans, with a linear β-(1→3)-glucan backbone and attached β-(1→6) branch. Structurally different β-glucans appear to have different affinities toward their receptors and thus generate markedly different host responses. However, their antitumor activities are mainly influenced by molecular mass, degree of branching, conformation, and structure modification of the polysaccharides. β-Glucans act on several immune receptors including Dectin-1, complement receptor (CR3) and TLR-2/6, then trigger both innate and adaptive response and enhance opsonic and nonopsonic phagocytosis. Various receptor interactions explain the possible mode of actions of polysaccharides.

Mycelium Polysaccharides from Termitomyces albuminosus Attenuate CCl4-Induced Chronic Liver Injury Via Inhibiting TGFβ1/Smad3 and NF-κB Signal Pathways

A major fraction (MPT-W), eluted by deionized water, was extracted from mycelium polysaccharides of Termitomyces albuminosus (MPT), and its antioxidant, anti-fibrosis, and anti-inflammatory activities in CCl₄-induced chronic liver injury mice, as well as preliminary characterizations, were evaluated. The results showed that MPT-W was a polysaccharide of α- and β-configurations containing xylose (Xyl), fucose (Fuc), mannose (Man), galactose (Gal), and glucose (Glc) with a molar ratio of 0.29:8.67:37.89:35.98:16.60 by gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FT-IR) spectroscopy. Its molecular weight (Mw), obtained by high-performance gel permeation chromatography (HPGPC), was 1.30 × 10⁵ Da. The antioxidant assays in vitro showed that MPT-W displayed scavenging free-radical abilities. Based on the data of in vivo experiments, MPT-W could inhibit TGFβ1/Smad3 and NF-κB pathways; decrease the level and activity of cytochrome P4502E1 (CYP2E1), malonaldehyde (MDA) and serum enzyme; activate the HO-1/Nrf2 pathway; and increase antioxidant enzymes to protect the liver in CCl₄-induced chronic liver injury mice. Therefore, MPT-W could be a potentially natural and functional resource contributing to antioxidant, hepatoprotective, and anti-inflammatory effects with potential health benefits.

Characterization, Antioxidant, Anti-Aging and Organ Protective Effects of Sulfated Polysaccharides from Flammulina velutipes

As an irreversible and complex degenerative physiological process, the treatment for aging seems strategically necessary, and polysaccharides play important roles against aging owing to their abundant bioactivities. In this paper, the antioxidant and anti-aging activities of Flammulina velutipes polysaccharides (FPS) and its sulfated FPS (SFPS) on d-galactose-induced aging mice were investigated. The in vitro antioxidant activities demonstrated that SFPS had strong reducing power and superior scavenging effects on 2, 2-diphenylpicrylhydrazyl (DPPH), hydroxyl radicals and the chelating activities of Fe²⁺. The in vivo animal experiments manifested that the SFPS showed superior antioxidant and protective abilities against the d-galactose-induced aging by increasing the antioxidant enzyme activities, decreasing lipid peroxidation, improving the inflammatory response and ameliorating the anile condition of mice. Furthermore, the structural analysis of SFPS was investigated through FT-IR, NMR, and HPLC analysis, and the results indicated that SFPS was a homogeneous heteropolysaccharide with a weight-average molecular weight of 2.81 × 10³ Da. Furthermore, SFPS has also changed in characteristic functional groups and monosaccharide composition compared to FPS. These results suggested that sulfated modification could enhance the anti-oxidation, anti-aging and protective activities of F. velutipes polysaccharides, which may provide references for the development of functional foods and natural medicines.

Effective Radiotherapy in Tumor Assisted by Ganoderma lucidum Polysaccharide-Conjugated Bismuth Sulfide Nanoparticles through Radiosensitization and Dendritic Cell Activation

Radiotherapy is a traditional method for cancer therapy but may become ineffective likely due to the radiation-induced immunosuppression. Instead of simply increasing the radiation dose, reactivation of immunosuppression in the tumor microenvironment is an alternative strategy for successful cancer treatment. In this work, we synthesized bismuth sulfide nanoparticles (BiNP) and conjugated with immunoactive Ganoderma lucidum polysaccharide (GLP). GLP-BiNP were able to increase the sensitivity of radiotherapy, attributing to the efficient X-ray absorption of bismuth element. BiNP alone can mildly activate dendritic cells (DC) in vitro, while GLP-BiNP further enhanced the level of DC maturation, shown as the increase in phenotypic maturation markers, cytokine release, acid phosphatase activity, and T cell proliferation in DC/T cell co-culture. Compared to BiNP, GLP-BiNP altered the tissue distribution with faster accumulation in the tumor. Meanwhile, mature DC greatly increased in both tumor and spleen by GLP-BiNP within 24 h. GLP-BiNP combination with radiation achieved remarkable inhibition of tumor growth through apoptosis. Alternatively, lung metastasis was largely prohibited by GLP-BiNP, shown as a reduced amount of tumor nodules and cancer cell invasion by pathological findings. Mechanistically, GLP-BiNP altered the tumor immunosuppression microenvironment by preferably increasing the number of intratumor CD8⁺ T cell proliferation, as well as the improved immunobalance shown as the increased serum interferon-γ/interleukin-4 ratio. Specifically, GLP conjugation seemed to protect the kidney from injury occasionally introduced by bare BiNP. As a result, GLP-BiNP play a dual role in tumor treatment through radiosensitization and immunoactivities.

Differences in the Moisture Capacity and Thermal Stability of Tremella fuciformis Polysaccharides Obtained by Various Drying Processes

We compared the proportions and differences in the polysaccharides of Tremella fuciformis (Berkeley) after drying them by various processes, such as 18 °C cold air, 50 °C hot air, and freeze-drying. We also focused on the moisture capacity kinetic parameters of Tremella fuciformis polysaccharides using various thermal analyses, including differential scanning calorimetry and thermogravimetric techniques. Erofeev's kinetic and proto-kinetic equations, utilized for kinetic model simulation, can predict the moisture capacity due to the thermal effect. Among the various drying processes, cold air-drying had the highest molecular weight of 2.41 × 10⁷ Da and a moisture content of 13.05% for Tremella fuciformis polysaccharides. Overall, the freeze-dried products had the best thermal decomposition properties under the conditions of a closed system, with an air or nitrogen atmosphere, and had an excellent moisture capacity of around 35 kJ/kg under a closed system for all samples.

Polysaccharides from Basidiocarps of Cultivating Mushroom Pleurotus ostreatus: Isolation and Structural Characterization

Oyster mushrooms are an interesting source of biologically active glucans and other polysaccharides. This work is devoted to the isolation and structural characterization of polysaccharides from basidiocarps of the cultivated oyster mushroom, Pleurotus ostreatus. Five polysaccharidic fractions were obtained by subsequent extraction with cold water, hot water and two subsequent extractions with 1 m sodium hydroxide. Branched partially methoxylated mannogalactan and slightly branched (1→6)-β-d-glucan predominated in cold- and hot-water-soluble fractions, respectively. Alternatively, these polysaccharides were obtained by only hot water extraction and subsequent two-stage chromatographic separation. The alkali-soluble parts originating from the first alkali extraction were then fractionated by dissolution in dimethyl sulfoxide (DMSO). The polysaccharide insoluble in DMSO was identified as linear (1→3)-α-d-glucan, while branched (1→3)(1→6)-β-d-glucans were found to be soluble in DMSO. The second alkaline extract contained the mentioned branched β-d-glucan together with some proteins. Finally, the alkali insoluble part was a cell wall complex of chitin and β-d-glucans.

The Antioxidant and Anti-Aging Effects of Acetylated Mycelia Polysaccharides from Pleurotus djamor

The present work mainly describes the preparation of acetylated mycelia polysaccharides (AMPS) from Pleurotus djamor and investigates the antioxidant and anti-aging effects in d-galactose-induced aging mice. The optimized procedure indicates the acetyl substitution degree of AMPS is 0.54 ± 0.04 under the conditions of a reaction time of 56 h, a reaction temperature of 37 °C, and 4 mL of added acetic anhydride. The in vitro analysis and in vivo animal experiments indicate that the AMPS could alleviate the aging properties by scavenging the radicals, elevating the enzyme activities, and reducing the lipid contents. As for serum levels, the AMPS can improve the serum biochemical indices and enhance immunological activity. The histopathological observations indicate that the injuries to the liver, kidney, and brain can be remitted by AMPS intervention. The characterization showed that AMPS was one kind of β-pyranose with the weight-average molecular weights of 3.61 × 105 Da and the major monosaccharides of mannose and glucose. The results suggest that AMPS can be used as a dietary supplement and functional food for the prevention of aging and age-related diseases.

Quantitative Analysis of Polysaccharide Composition in Polyporus umbellatus by HPLC-ESI-TOF-MS

Polyporus umbellatus is a well-known and important medicinal fungus in Asia. Its polysaccharides possess interesting bioactivities such as antitumor, antioxidant, hepatoprotective and immunomodulatory effects. A qualitative and quantitative method has been established for the analysis of 12 monosaccharides comprising polysaccharides of Polyporus umbellatus based on high-performance liquid chromatography coupled with electrospray ionization–ion trap–time of flight–mass spectrometry. The hydrolysis conditions of the polysaccharides were optimized by orthogonal design. The results of optimized hydrolysis were as follows: neutral sugars and uronic acids 4 mol/L trifluoroacetic acid (TFA), 6 h, 120 °C; and amino sugars 3 mol/L TFA, 3 h, 100 °C. The resulting monosaccharides derivatized with 1-phenyl-3-methyl-5-pyrazolone have been well separated and analyzed by the established method. Identification of the monosaccharides was carried out by analyzing the mass spectral behaviors and chromatography characteristics of 1-phenyl-3-methyl-5-pyrazolone labeled monosaccharides. The results showed that polysaccharides in Polyporus umbellatus were composed of mannose, glucosamine, rhamnose, ribose, lyxose, erythrose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, and fucose. Quantitative recoveries of these monosaccharides in the samples were in the range of 96.10–103.70%. This method is simple, accurate, and sensitive for the identification and quantification of monosaccharides, and can be applied to the quality control of Polyporusumbellatus as a natural medicine.

A Review: The Bioactivities and Pharmacological Applications of Phellinus linteus

Phellinus linteus is a popular medicinal mushroom that is widely used in China, Korea, Japan, and other Asian countries. P. linteus comprises various bioactive components, such as polysaccharides, triterpenoids, phenylpropanoids, and furans, and has proven to be an effective therapeutic agent in traditional Chinese medicine for the treatment and the prevention of various diseases. A number of studies have reported that P. linteus possesses many biological activities useful for pharmacological applications, including anticancer, anti-inflammatory, immunomodulatory, antioxidative, and antifungal activities, as well as antidiabetic, hepatoprotective, and neuroprotective effects. This review article briefly presents the recent progress made in understanding the bioactive components, biological activities, pharmacological applications, safety, and prospects of P. linteus, and provides helpful references and promising directions for further studies of P. linteus.

Studies on the anti-fatigue activities of Irpex lacteus polysaccharide-enriched extract in mouse model

Irpex lacteus is a white rot basidiomycete proposed for a wide spectrum of biotechnological applications. However, few studies examined its effects on exercise performance and physical fatigue. The present study evaluated the potential beneficial effects of I. lacteus extract (ILE) on physical fatigue in mice. Anti-fatigue activities of ILE were evaluated in Kunming mice using the forced swim test, rotating rod and forced running test. Serum and liver biochemical parameters were determined by an autoanalyzer and commercially available kits. Seven-day ILE administration at doses of 0.04, 0.2 and 1.0g/kg failed to influence mouse horizontal and vertical movement indicating its safety on the central nervous system. Compared with normal mice, ILE significantly increased persistent period during rotating rod and swimming tests, and reduced shock times in forced running test. Additionally, ILE resulted in 23.4% and 64.5% increments on adrenocorticotropic hormone and cortisol levels in serum. Compared with normal mice, and 209.0% increment on adenosine triphosphate level in liver (up to 2.5 mmol/gHb) were noted in ILE-treated mice. Moreover, ILE increased the level of super oxide dismutase and reduced the level of malondialdehyde in the liver suggesting its antioxidant activity. Data obtained from western bolt suggests that ILE-improved endurance capacity is mainly acquired through activating 5'-AMP-activated protein kinase (AMPK). ILE enhanced the endurance capacity of mouse by an elevation of antioxidant at least partially associated with AMPK pathway. Our data highlight the potential of I. lacteus as an antioxidant in the treatment of fatigue-related diseases.

Structure and Anti-Tumor Activities of Exopolysaccharides from Alternaria mali Roberts

In this study, an extracellular polysaccharide from Alternaria mali Roberts (AMEP) was extracted, and its structure was characterized, in addition to its antitumor activity in vitro. Neutral polysaccharide AMEP-1 and anionic polysaccharide AMEP-2 were isolated from AMEP, and their monosaccharide compositions consisted of mannose (Man), glucose (Glc), and galactose (Gal) but at different ratios. The linking mode of both AMEP-1 and AMEP-2 is Manp-(1→4) and Glcp-(1→6), and the branched chains are connected to the main chain through O-6. AMEP-2 inhibited the proliferation of BGC-823 cells in a time- and concentration-dependent manner. AMEP-2 also induced the apoptosis of BGC-823 cells, and showed anti-tumor effects by inducing cell cycle arrest in the S phase, reactive oxygen species production, and mitochondrial membrane potential reduction in BGC-823 cells. Therefore, AMEP-2 shows potential for further development as a novel anti-tumor agent.

Three exopolysaccharides from the liquid fermentation of Polyporus umbellatus and their bioactivities

The exopolysaccharides were extracted and separated from the broth of the liquid fermentation of P. umbellatus, and the antioxidant activities and other relative bioactivities were investigated, aiming to find clues for a wider use in the future. Three novel exopolysaccharides of PPS1, PPS2 and PPS3 with molecular weight of 3.7×10⁴-6.9×10⁴Da were obtained. Monosaccharide analysis showed that they were mainly composed of mannose, along with galactose and glucose with different molar ratio, and their structural features were also investigated by FT-IR, NMR and SEM. The antioxidant activity assay in vitro showed these exopolysaccharides exhibited a significant scavenging effect on DPPH· and other free radicals in a dose-dependent manner. Significantly, the stimulate nitric oxide production and phagocytic activity implied that the polysaccharides could enhance the immunity of RAW 264.7 macrophages. Other assays revealed that they have obvious cellular aging delaying activity and the DNA damage protecting activity. In conclusion, these three exopolysaccharides might have potential applications in the fields of pharmaceuticals, cosmetics, and food products.

Extraction, characterization and antioxidant activity analysis of the polysaccharide from the solid-state fermentation substrate of Inonotus hispidus

A polysaccharide from Inonotus hispidus was prepared by solid-state fermentation (SSF), and an efficient ultrasound-assisted extraction method was used to optimize the extraction process of Inonotus hispidus solid-state fermentation polysaccharide (IHSFP). The optimal extraction parameters were as follows: solid-liquid ratio of 1:40, ultrasound time of 34 min, ultrasound power of 350 W and ultrasound temperature of 70 °C. The yield of IHSFP was 51.06 ± 0.34% under the optimal conditions. Two types of polysaccharide fractions (IHSFP-1 and IHSFP-2) were isolated by DEAE-52 and Sephadex G-200 columns. IHSFP-2 had stronger antioxidant activity than IHSFP-1, and it can reduce H₂O₂-induced oxidative damage to cells in vitro. Therefore, the properties of IHSFP-2 were further characterized. The results showed that the molecular weight of IHSFP-2 was 14.44 kDa, it was composed of glucose (Glc), mannose (Man), galactose (Gal), glucuronic acid (GlcUA), galactosamine (GalN), arabinose (Ara) and ribose (Rib), and the contents of these monosaccharides were 51%, 21%, 20%, 3%, 2%, 2% and 1%, respectively. The results of this study may contribute to the efficient production of the polysaccharide of Inonotus hispidus, and provide new ideas for its application in functional foods and cosmetics.

Anti-hyperlipidemic, antioxidant and organic protection effects of acidic-extractable polysaccharides from Dictyophora indusiata

In the present work, we investigated the anti-hyperlipidemic, antioxidant and organic protection effects of acidic-extractable Dictyophora indusiata polysaccharides (Ac-DPS) on hyperlipidemic mice induced by high-fat emulsion. The results demonstrated that Ac-DPS had impressive abilities to mitigate oxidative stress by increasing the activities of antioxidant enzyme and reducing the contents of lipid peroxide. Moreover, lipid levels in serum were returned to normal status. Besides, Ac-DPS exhibited potential hepatic and renal protection effects reflected by decreasing serum enzyme activities, lowering TBIL, UREA and CREA levels and increasing ALB content. At the same time, histopathological observations proved protective effects of Ac-DPS on organs. Subsequently, the physical properties of polysaccharide were also investigated by HPGPC and FT-IR. The above consequences confirmed the important role of Ac-DPS as a functional food and natural medicine in the fight against oxidative stress and the prevention of hyperlipidemia.

Molecular characterization of the effects of Ganoderma Lucidum polysaccharides on the structure and activity of bovine serum albumin

The investigation about polysaccharides-protein system is attributed to numerous very important applications for pharmaceutical, food, chemical and other industries. In the present work, multi-spectral methods and molecular docking were used to analyze the molecular interactions of polysaccharides from Ganoderma Lucidum (GLP) with bovine serum albumin (BSA). The nonenzymatic glucosylation, fibrillation, thermal stability, and structure information of GLP-BSA system were also studied. The results showed that the formation of GLP-BSA complex by mainly hydrogen-bonding forces resulted in the conformational changes of protein. GLP acted as a stabilizer to increase the thermal stability of BSA solution having a novel and more stable conformational state during the thermal denaturation process. 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence spectral results suggested that there exist some intermediate state which has low binding ability with ANS in the presence of GLP. The presence of GLP caused a decrease in the formation of beta sheet structures with a lower rate. The fluorescence spectra of BSA glycosylated by GLP confirmed the formation of covalent bonds between BSA and GLP through the Maillard reaction which was also confirmed by using thermogravimetric (TGA) and Fourier transform infrared (FTIR) analysis. In addition, BSA still maintains the esterase-like good activity in the presence of GLP. These results provide a basis for screening the molecular interactions of polysaccharides with protein from the perspective of important food active ingredients.

Synthetic Oligosaccharides Mimicking Fungal Cell Wall Polysaccharides

The cell wall of pathogenic fungi is highly important for the development of fungal infections and is the first cellular component to interact with the host immune system. The fungal cell wall is mainly built up of different polysaccharides representing ligands for pattern recognition receptors (PRRs) on immune cells and antibodies. Purified fungal polysaccharides are not easily available; in addition, they are structurally heterogenic and have wide molecular weight distribution that limits the possibility to use natural polysaccharides to assess the structure of their active determinants. The synthetic oligosaccharides of definite structure representing distinct polysaccharide fragments are indispensable tools for a variety of biological investigations and represent an advantageous alternative to natural polysaccharides. The attachment of a spacer group to these oligosaccharides permits their efficient transformation into immunogenic glycoconjugates as well as their immobilization on plates or microbeads. Herein, we summarize current information on synthetic availability of the variety of oligosaccharides related to main types of fungal cell wall components: galactomannan, α- and β-mannan, α- and β-(1 → 3)-glucan, chitin, chitosan, and others. These data are supplemented with published results of biochemical and immunological applications of synthetic oligosaccharides as molecular probes especially as the components of thematic glycoarrays suitable for characterization of anti-polysaccharide antibodies and cellular lectins or PRRs.

Evaluation of the production of exopolysaccharide by plant growth promoting yeast Rhodotorula sp. strain CAH2 under abiotic stress conditions

The capability of plant growth promoting microbes to survive under abiotic stresses has important significance for improving plant growth and productivity. Among the various plant growth promoting biomolecules produced by microbes, exopolysaccharide (EPS) help microbes to survive in inhospitable environments and endure environmental stressful conditions. In the present study, a yeast strain CAH2 was isolated from Beta vulgaris rhizosphere soil and identified as Rhodotorula sp., based on the partial 18S rRNA gene sequence analysis. Rhodotorula sp. strain CAH2 was found to tolerate higher concentrations of Al (6 mM), NaCl (150 mM) and PEG-6000 (15%, w/v). The strain CAH2 was shown to produce 7.5 g L^-1 of EPS in the production medium with sucrose and yeast extract as a carbon and nitrogen sources, respectively. The EPS yield was increased constantly with increasing concentrations of Al, NaCl and PEG-6000. The structural feature of EPS studied through FT-IR and NMR spectral analysis confirmed the presence of glucose, mannose and galactose. The yeast strain CAH2 was produced multiple plant growth promoting traits in the presence and absence of abiotic stresses. Finally, these results indicate that the production of EPS could be safeguard the plant growth promoting Rhodotorula sp. strain CAH2 from unfavourable environmental conditions.

Se-enriched G. frondosa polysaccharide protects against immunosuppression in cyclophosphamide-induced mice via MAPKs signal transduction pathway

To assess the immunomodulatory and antioxidant activities of a Se-polysaccharide from Se-enriched G. frondosa (Se-GFP-22), immunosuppressed mice models were generated by cyclophosphamide (CTX) administration and then treated with Se-GFP-22. Results showed that Se-GFP-22 could increase thymus and spleen indices, phagocytic index, co-mitogenic (ConA- or LPS-stimulated) activities on splenocytes, DTH reaction, serum hemolysin formation and immunoglobulin (Ig G, Ig A and Ig M) levels in CTX-treated mice. Se-GFP-22 significantly enhanced the antioxidant activity in CTX-treated mice, as shown by the evaluation of GSH-Px, SOD and CAT activities, as well as MDA levels in serum, liver and kidney. Se-GFP-22 strongly stimulated inflammatory cytokines (IL-2 and IFN-γ) and NO productions by up-regulating mRNA expressions of IL-2, IFN-γ and iNOS. Se-GFP-22 possessed the immunomodulatory activity by up-regulating various transcription factors (JNK, ERK, and p38) in MAPKs signaling pathways. This study suggested that Se-GFP-22 may provide an alternative strategy in lessening chemotherapy-induced immunosuppression.

Functional characterization of a lytic polysaccharide monooxygenase from the thermophilic fungus Myceliophthora thermophila

Thermophilic fungi are a promising source of thermostable enzymes able to hydrolytically or oxidatively degrade plant cell wall components. Among these enzymes are lytic polysaccharide monooxygenases (LPMOs), enzymes capable of enhancing biomass hydrolysis through an oxidative mechanism. Myceliophthora thermophila (synonym Sporotrichum thermophile), an Ascomycete fungus, expresses and secretes over a dozen different LPMOs. In this study, we report the overexpression and biochemical study of a previously uncharacterized LPMO (MtLPMO9J) from M. thermophila M77 in Aspergillus nidulans. MtLPMO9J is a single-domain LPMO and has 63% sequence similarity with the catalytic domain of NcLPMO9C from Neurospora crassa. Biochemical characterization of MtLPMO9J revealed that it performs C4-oxidation and is active against cellulose, soluble cello-oligosaccharides and xyloglucan. Moreover, biophysical studies showed that MtLPMO9J is structurally stable at pH above 5 and at temperatures up to 50°C. Importantly, LC-MS analysis of the peptides after tryptic digestion of the recombinantly produced protein revealed not only the correct processing of the signal peptide and methylation of the N-terminal histidine, but also partial autoxidation of the catalytic center. This shows that redox conditions need to be controlled, not only during LPMO reactions but also during protein production, to protect LPMOs from oxidative damage.

Molecular architecture of fungal cell walls revealed by solid-state NMR

The high mortality of invasive fungal infections, and the limited number and inefficacy of antifungals necessitate the development of new agents with novel mechanisms and targets. The fungal cell wall is a promising target as it contains polysaccharides absent in humans, however, its molecular structure remains elusive. Here we report the architecture of the cell walls in the pathogenic fungus Aspergillus fumigatus. Solid-state NMR spectroscopy, assisted by dynamic nuclear polarization and glycosyl linkage analysis, reveals that chitin and α-1,3-glucan build a hydrophobic scaffold that is surrounded by a hydrated matrix of diversely linked β-glucans and capped by a dynamic layer of glycoproteins and α-1,3-glucan. The two-domain distribution of α-1,3-glucans signifies the dual functions of this molecule: contributing to cell wall rigidity and fungal virulence. This study provides a high-resolution model of fungal cell walls and serves as the basis for assessing drug response to promote the development of wall-targeted antifungals.

Ultrasound-Assisted Extraction of Polysaccharides from Volvariella volvacea: Process Optimization and Structural Characterization

The aims of the present study were to optimize the operational parameters to maximize the yield of ultrasound-assisted polysaccharide extraction from Volvariella volvacea (straw mushroom) fruiting bodies by using for the first time one-factor-at-a-time and three-level Box-Behnken factorial designs. A maximum polysaccharide yield of 8.28 ± 0.23% was obtained under the optimized conditions of ultrasound power of 175 W, extraction temperature of 57 °C, extraction time of 33 min, and the ratio of liquid to raw material of 25:1, respectively. Compared to the hot-water extraction, the ultrasound-assistance favored the extraction of polysaccharides from V. volvacea for its higher polysaccharide yield and efficiency. Further preliminary polysaccharide structural characterization indicated that ultrasound treatment affected the monosaccharide compositions and ratios, and molecular weight range of polysaccharides extracted from V. volvacea.

Chemical, biochemical, preclinical and clinical studies of Ganoderma lucidum polysaccharide as an approved drug for treating myopathy and other diseases in China

Ganoderma lucidum is an edible medicinal mushroom known as "Lingzhi" in China and "Reishi or Manetake" in Japan. It is a highly prized vitality-enhancing herb for more than 2000 years. G. lucidum polysaccharide (GLPS) has been identified as one of the major bioactive components and developed into a drug named "Ji 731 Injection" in China since 1973. The large-scale production of the drug began in 1985 and approved by the Chinese FDA as "Polysaccharidum of G. lucidum Karst Injection" (Ling Bao Duo Tang Zhu She Ye) in 2000, which is applied intramuscularly. After more than forty years of clinical use, its efficacy, safety and long-term tolerability have been recognized by neurologists. It is one of a few non-hormonal drugs used for treating refractory myopathy. It is also used for combination therapy, which reduces the amount of glucocorticoid required for myopathy patient who is in remission. In addition, it reduces adverse reactions and improves the quality of life for cancer patients during chemotherapy. We found 81 qualified chemical, biochemical, preclinical and clinical studies of GLPS both in English and in Chinese spanning from 1973 to 2017 by searching CNKI (China National Knowledge Infrastructure), Wanfang database and PubMed. The molecular mechanisms underlying GLPS's antioxidant, anti-tumour, immune-modulatory, hypoglycaemic, hypolipidaemic and other activities are discussed. Both preclinical and clinical studies are either deliberated or indexed in the current article. We aimed at providing a molecular picture as well as a clinical basis to comprehend GLPS as one of few polysaccharide-based modern medicines with complicated chemical and pharmacological properties that prevent it from entering the world's market.

Mycorrhizal lipochitinoligosaccharides (LCOs) depolarize root hairs of Medicago truncatula

Arbuscular Mycorrhiza and Root Nodule Symbiosis are symbiotic interactions with a high benefit for plant growth and crop production. Thus, it is of great interest to understand the developmental process of these symbioses in detail. We analysed very early symbiotic responses of Medicago truncatula root hair cells, by stimulation with lipochitinoligosaccharides specific for the induction of nodules (Nod-LCOs), or the interaction with mycorrhiza (Myc-LCOs). Intracellular micro electrodes were used, in combination with Ca2+ sensitive reporter dyes, to study the relations between cytosolic Ca2+ signals and membrane potential changes. We found that sulfated Myc- as well as Nod-LCOs initiate a membrane depolarization, which depends on the chemical composition of these signaling molecules, as well as the genotype of the plants that were studied. A successive application of sulfated Myc-LCOs and Nod-LCOs resulted only in a single transient depolarization, indicating that Myc-LCOs can repress plasma membrane responses to Nod-LCOs. In contrast to current models, the Nod-LCO-induced depolarization precedes changes in the cytosolic Ca2+ level of root hair cells. The Nod-LCO induced membrane depolarization thus is most likely independent of cytosolic Ca2+ signals and nuclear Ca2+ spiking.

Characterization and interplay of bacteriocin and exopolysaccharide-mediated silver nanoparticles as an antibacterial agent

Metallic nanoparticles have a substantial scientific interest because of their distinctive physicochemical and antimicrobial properties and the emergence of multidrug resistant pathogens could unlock the potential of nanoparticles to combat infectious diseases. The aim of the current study is to enhance the antibacterial potential of purified bacteriocin by combining bacteriocin and antibacterial silver nanoparticles (AgNPs). Hence, the interaction of natural antimicrobial compounds and antibacterial nanoparticles can be used as a potential tool for combating infectious diseases. In this study, a green, simple and effective approach is used to synthesize antibacterial AgNPs using fungal exopolysaccharide as both a reducing and stabilizing agent. The AgNPs were characterized by spectroscopic analysis, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX) and Dynamic Light Scattering (DLS). Furthermore, the synergistic effect of bacteriocin-AgNPs was determined against pathogenic strains. The histogram of AgNPs indicated well-dispersed, stabilized and negatively charged particles with variable size distribution. The combination of bacteriocin with nanoparticles found to be more effective due to broad antibacterial potential with possibly lower doses. The current study is imperative to provide an alternative for the chemical synthesis of silver nanoparticles. It showed environmental friendly and cost effective green synthesis of antibacterial nanoparticles.