Immobilization of Coprinus comatus with magnetic alginate hydrogel microsphere for improving the antioxidant activity of fermentation products

Coprinus comatus is an edible mushroom and its fermented product possesses antioxidant activity. In this study, to further enhance the antioxidant activity and improve the reusability of the strain, calcium alginate hydrogel was used as the carrier for embedding and immobilizing Coprinus comatus. The effects of CaCl2 concentration, sodium alginate concentration, microsphere diameter, and the amount of magnetic particle on the antioxidant activity of fermented products were investigated. The results showed that the magnetic immobilized microsphere prepared by 2.50% CaCl2, 2.00% sodium alginate and 0.50% Fe3O4 had the best fermentation antioxidant activity (EC50 was 0.43 ± 0.01 mg/mL) when the diameter was 5 mm, which increased by 24.56% compared to the initial activity. Besides, the microsphere showed strong reusability, the antioxidant activity was still better than the free strain after being used five times. This study not only enhanced the antioxidant activity of Coprinus comatus fermented product through immobilization, but also provided an effective method for microbial fermentation.

Optimization of liquid fermentation conditions for Coprinus comatus to enhance antioxidant activity

Coprinus comatus is an edible and medicinal fungus. In this study, the antioxidant activity of the fermentation product of C. comatus was investigated through optimization of fermentation process. The results indicated that the fermentation product of C. comatus had obvious scavenging ability for 2,2'-Azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) free radical. The EC50 of the n-butanol extract from the fermentation product on ABTS·+ was 0.65 ± 0.02 mg/mL. On this basis, the liquid fermentation conditions of C. comatus were optimized through single factor and response surface optimization experiments according to the scavenging ability of ABTS·+ to improve the antioxidant capacity of the fermentation product. The results showed that when the 14% of C. comatus was fermented in a culture medium with a C/N ratio of 48:1 for 6 days, the ABTS·+ scavenging ability was the strongest, and the EC50 of n-butanol extract was 0.57 ± 0.01 mg/mL, which was 12.31% higher than the initial activity. This study laid the foundation for the development of C. comatus.

Response surface methodology for the mixed fungal fermentation of Codonopsis pilosula straw using Trichoderma reesei and Coprinus comatus

The objective of this study was to investigate the cellulose degradation rate (CDR) and lignin degradation rate (LDR) of Codonopsis pilosula straw (CPS) and the optimal fermentation parameters for mixed fungal fermentation. Single-factor tests were used to study the effects of the fungal ratio (Trichoderma reesei: Coprinus comatus), fungal inoculum, corn flour content, and fermentation time on the degradation rate of cellulose and lignin. Based on the results of this experiment, the optimal fermentation factors were identified, and the effects of various factors and their interactions on the degradation rates of cellulose and lignin were further evaluated using the response surface method. The quadratic polynomial mathematical model of degradation rates of the cellulose and lignin in CPS by mixed fungus fermentation was established using Design Expert software v8.0.6. Under the optimal parameters for fungal fermentation of CPS straw (fungal ratio 4:6, fungal inoculum 8%, corn flour content 10%, fermentation time of 15 d), the CDR and LDR reached 13.65% and 10.73%, respectively. Collectively, the mixed fungal fermentation of CPS resulted in decreased lignin and cellulose content, better retention of nutrients, and enhanced fermentation quality. The results of this study indicate that fermentation using Trichoderma reesei and Coprinus comatus is a productive method for straw degradation, providing a theoretical basis for the development of CPS as feed.

Physicochemical characterization, adsorption function and prebiotic effect of chitin-glucan complex from mushroom Coprinus comatus

Chitin-glucan complex (CGC) is a novel insoluble dietary fiber with multiple physiological activities. In this work, CGC was extracted from the fruiting body of Coprinus comatus and its physicochemical properties and prebiotic effects were investigated. The results indicated that CGC consisted of glucosamine and glucose in a molar ratio of 67: 33 with degree of acetylation of 61.91% and crystallinity index of 25.40%. The maximum degradation temperature was determined to be 307.52 °C, and a woven fibrous structure was observed by scanning electron microscopy. CGC exhibited higher oil-holding capacity, water-holding capacity and nitrite ion adsorption capacity than commercial chitin, and showed potential prebiotic effects. Compared with control and commercial chitin, CGC significantly (P < 0.05) increased the concentration of propionic and butyric acids. These results suggested that CGC from C. comatus was promising to be an alternative source of CGC products and used as a bioactive ingredient in functional foods.

Proteomics Reveals the Mechanism Underlying the Autolysis of Postharvest Coprinus comatus Fruiting Bodies

Autolysis occurs widely in edible mushroom fruiting bodies after harvest, but the mechanism is still unclear. In this study, quantitative proteomics and bioinformatics analyses have been applied for revealing the autolysis mechanism of postharvest Coprinus comatus fruiting bodies. The results indicated that the autolysis mechanism of postharvest C. comatus was complicated. Before pileus opening, the carbohydrate metabolism including cell wall hydrolysis and energy biosynthesis, which were probably regulated by the ribosome, was involved in mushroom autolysis, whereas after pileus opening, the autolysis mechanism was related to the accumulated reactive oxygen species (ROS) and activated mitogen-activated protein kinase (MAPK) signaling pathway based on the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Furthermore, the changes in cell wall components and hydrolases, along with the production of ROS and the activities of oxidoreductase in C. comatus, were also verified to confirm the proteomic analysis results.

Impacts and tolerance responses of Coprinus comatus and Pleurotus cornucopiae on cadmium contaminated soil

Large amounts of cadmium (Cd) have been discharged into soil with the rapid development of industry. In this study, we revealed the impacts of Coprinus comatus (C. comatus) and Pleurotus cornucopiae (P. cornucopiae) on soil and the tolerance responses of macrofungi in the presence of Cd by the analysis of soil biochemical properties and macrofungi growth indexes. Results showed that with the cultivation of C. comatus and P. cornucopiae, the HOAc-extractable Cd in soil individually reduced by 9.53% and 11.35%, the activities of soil urease, acid phosphatase, dehydrogenase, and Fluorescein diacetate (FDA) hydrolysis increased by 18.11-101.45%, 8.39-18.24%, 9.37-55.50% and 28.94-41.92%, respectively. Meanwhile, different soil bacterial communities were observed with various macrofungi cultivations. Also, Cd accumulation significantly enhanced the macrofungi antioxidant enzyme activities, which increased by 24.10-45.43%, 30.11-61.53% and 7.03-26.81% for catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities in the macrofungi, respectively. Moreover, the enhanced macrofungi endophytic bacterial diversities with Cd existence was firstly observed in the present experiment. These findings revealed the possible Cd resistance mechanisms in macrofungi, suggesting C. comatus and P. cornucopiae were promising ameliorators for Cd contaminated soil.

Characterization and anti-diabetic nephropathic ability of mycelium polysaccharides from Coprinus comatus

It seems quite necessary for obtaining effective substances from natural products against the diabetic nephropathic (DN) with the presently clinical problems of accompanying side-effects and lowing life qualities. This work aimed to characterize the primary structure of Coprinus comatus mycelium polysaccharides (CMP) and investigate the abilities against DN in streptozotocin induced mice models. The results indicated that CMP could improve insulin resistance and energy metabolism, and significantly suppress dysfunction on kidney and relieve the renal oxidative stress and inflammation in DN mice. Besides, the western blot results suggested that CMP reversed renal injury by modulating the PTEN/PI3K/Akt and Wnt-1/β-catenin pathways. The structure analysis indicated the typical characterizations with the major monosaccharide-compositions of galactose, α-pyranose configuration and proper molecular weights of 495.8 kDa possibly contributed to the anti-diabetic nephropathic effects of CMP. The results suggested that polysaccharides form C. comatus could be used as functional foods/drugs on preventing diabetic nephropathy.

Comparison of the structures and prebiotic-like effects in vitro of polysaccharides from Coprinus comatus fruit body and mycelium

Many effects of Coprinus comatus are attributed to its polysaccharide components. Therefore, the aim of this article is to take Coprinus comatus polysaccharides as the research topic to estimate the difference between the polysaccharides of Coprinus comatus fruiting bodies (CBPs) and the intracellular polysaccharides of liquid fermentation (ICPs). The total carbohydrate contents, monosaccharide compositions, molecular weights, functional groups, microstructures and functional properties of the two prepared polysaccharides were evaluated. At the same time, the influences of the two polysaccharides on the proliferation of lactobacillus and Bifidobacterium in vitro were compared. The structural analysis exhibited that there were slight differences in the two prepared polysaccharides. However, both ICPs and CBPs could be utilized by these two strains. Furthermore, the effects of the two prepared polysaccharides on the proliferation of the selected probiotics were dose-dependent manners within the scope of the experiment, and the ICPs group and CBPs group had no significant difference (P > 0.05). Therefore, this work demonstrates that ICPs could be an equivalent replacer for CBPs.

Chemical composition, nutritional profile and in vivo antioxidant properties of the cultivated mushroom Coprinus comatus

This study investigated the chemical and nutritional profile and antioxidative properties of cultivated Coprinus comatus. Proximate analysis revealed that C. comatus is rich in carbohydrates, dietary fibres and proteins, and could also be a valuable source of phenolics. Additionally, fat content is low, consisting mainly of polyunsaturated and omega-3 fatty acids. Furthermore, the safety profile of C. comatus is satisfactory, with all elements of toxicological importance within the proposed limits. Oral treatment with C. comatus for 42 days improved the antioxidant capabilities and ameliorated carbon tetrachloride-induced liver damage in rats, marked by decreased serum aminotransferase levels and lipid peroxidation intensity. Glutathione concentrations increased in a dose-dependent manner. Histological morphometric and immunohistochemical analysis confirmed antioxidative and hepatoprotective potential. These findings imply that cultivated C. comatus could be considered a nutraceutical, having beneficial nutrient and therapeutic properties.

Inhibitory effect of protein Y3 from Coprinus comatus on tobacco mosaic virus

The antiviral protein Y3 produced by the edible mushroom Coprinus comatus disrupts the tobacco mosaic virus (TMV) and inhibits the multiplication of TMV in Nicotiana tabacum; however, the detailed mechanism of its activity remains unclear. In this study, Y3 was demonstrated to interact with TMV coat protein (TMV-CP) in vitro as well as in tobacco plants by using a yeast two-hybrid system and bimolecular fluorescence complementation (BiFC). To explore the interaction site between Y3 and TMV-CP, the phenylalanine (Phe) at the 43rd and arginine (Arg) at the 55th amino acid of Y3 were individually converted to cysteine (Cys) and serine (Ser), named Y3T1 and Y3T2, respectively, and were then used in BiFC assays. Based on the information obtained about disulfide bonds in the protein structure, the two mutations were predicted to change the protein's disulfide bonds. The results showed Y3T1 lost the ability to interact with TMV-CP, suggesting that a specific Phe of Y3 is critical for the interaction between Y3 and CP in plants. Furthermore, a prokaryotic expression system was used to test the antiviral activities of protein Y3 (PY3) and two other mutated proteins (P-Y3T1, P-Y3T2). The results showed that recombinant protein P-Y3 had a slightly lower inhibitory effect against TMV than Y3 extracted directly from mushrooms; further, P-Y3T1 decreased antiviral activity in the tobacco plant significantly compared with P-Y3, suggesting that the anti-TMV effect of Y3 was directly related to the Y3-CP interaction. In contrast, P-Y3T2 was able to still interact with TMV-CP in the tobacco plant, and it increased the ability of the plant to resist TMV compared with PY3, indicating that PY3-T2 could be a candidate peptide for plant protection against TMV and that Y3 may have other inhibitory mechanisms against TMV in addition to its interaction with TMV-CP.

The two faces of Coprinus comatus-Functional properties and potential hazards

Mushrooms have been used for centuries not only as food but also in traditional medicine as a source of components with pro‐health activity. One of them is Coprinus comatus (O.F.Müll.) Pers. also called shaggy mane, chicken drumstick mushroom, or lawyer's wig. In Asian countries, C. comatus (CC) is approved as edible mushroom and often cultivated for consumption, whereas in many other countries, although it is widespread, it is unrecognized and not used. In this review, for the first time, we discussed about the composition related to functional properties as well as the potential risks associated with consumption of CC by reviewing scientific literature. The information has been collected in order to get to know this species thoroughly. Various studies show many of the physiological activities, such as antioxidant, anticancer, antiandrogenic, hepatoprotective, acetylcholinesterase inhibitory, antiinflammatory, antidiabetic, antiobesity, antibacterial, antifungal, antinematode, and antiviral. Besides positive physiological properties, CC has also negative features, for example, skin reactions in patients with dermatitis and atopic predisposition, risk of confusion with poisonous mushrooms, quick autolysis after collection, and contamination of toxic elements.

Fatty Acids Predominantly Affect Anti-Hydroxyl Radical Activity and FRAP Value: The Case Study of Two Edible Mushrooms

Compared to plants, nowadays mushrooms attract more attention as functional foods, due to a number of advantages in manipulating them. This study aimed to screen the chemical composition (fatty acids and phenolics) and antioxidant potential (OH•, 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and ferric reducing ability of plasma (FRAP)) of two edible mushrooms, Coprinus comatus and Coprinellus truncorum, collected from nature and submerged cultivation. Partial least square regression analysis has pointed out the importance of some fatty acids—more precisely, unsaturated fatty acids (UFAs) followed by fatty acids possessing both short (C6:0 and C8:0) and long (C23:0 and C24:0) saturated chains—and phenolic compounds (such as protocatechuic acid, daidzein, p-hydroxybenzoic acid, genistein and vanillic acid) for promising anti-OH•, FRAP and anti-DPPH• activities, respectively. However, other fatty acids (C16:0, C18:0 and C18:3n3) along with the flavonol isorhamnetin are actually suspected to negatively affect (by acting pro-oxidative) the aforementioned parameters, respectively. Taken together, design of new food supplements targeting oxidative stress might be predominantly based on the various UFAs combinations (C18:2n6, C20:1, C20:2, C20:4n6, C22:2, C22:1n9, etc.), particularly if OH• is suspected to play an important role.

Antioxidant and hepatoprotective activities of modified polysaccharides from Coprinus comatus in mice with alcohol-induced liver injury

A modified polysaccharide named MPCC from Coprinus comatus (MPCC) was obtained by the snailase hydrolysis. And the hepatoprotective effects on alcohol-induced liver injury and preliminary structure features were investigated. For in vivo hepatoprotective abilities, MPCC significantly attenuated the hepatic and serum lipid levels, obviously enhanced antioxidant enzyme activities, markedly improved alcohol metabolism system and inflammatory response, and mitigated alcohol-induced liver injury histopathologically, providing references for the exploitation of MPCC as functional foods or natural drugs against the alcohol-induced liver injury. Additionally, MPCC containing fucose (Fuc), ribose (Rib), arabinose (Ara), xylose (Xyl), mannose (Man), galactose (Gal) and glucose (Glu) with the a α- and β-configuration in a percentage composition of 0.91%, 0.71%, 0.45%, 1.60%, 2.04%, 4.41% and 89.88% via gas chromatography (GC), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analysis.

Effects of vanadate on the mycelium of edible fungus Coprinus comatus

Vanadate is proposed to play a pivotal role in application of edible fungus Coprinus comatus for medical purposes. In this study the concentration of extracellular vanadate acceptable for the submerged cultivation of C. comatus mycelium was established. The mycelium could grow, and overcome vanadate toxic effects, up to the concentration of 3.3 mM. Moreover, in this condition, at the end of the exponential phase of growth, biomass yield was almost identical to that in the control. ³¹P NMR spectroscopy showed that addition of 10 mM vanadate to the mycelium in the exponential phase of growth provoked instantaneous increase of a sugar phosphates level which could be related to changes in activities of glycolytic enzymes. Exposure to higher vanadate concentration was toxic for the cell. ⁵¹V NMR measurements revealed that monomer of vanadate is present in the cytoplasm causing the metabolic changes. C. comatus has also capacity for vanadate reduction, as shown by EPR measurements, but vanadyl uptake is significantly less comparing to vanadate.

Total flavones of fermentation broth by co-culture of Coprinus comatus and Morchella esculenta induces an anti-inflammatory effect on LPS-stimulated RAW264.7 macrophages cells via the MAPK signaling pathway

The inflammatory cellular model of RAW264.7 cells induced by lipopolysaccharide (LPS) has always been used to investigate the effect of anti-inflammatory agents in vitro. In the present study, the anti-inflammatory activity of total flavones extracted from the fermentation broth of the co-culture of Coprinus comatus and Morchella esculenta (MCF-F), and its potential molecular mechanism in LPS-challenged RAW264.7 macrophage cells were investigated. The data revealed that MCF-F exhibited anti-inflammatory activity in LPS-stimulated RAW264.7 cells. At the same time, MCF-F was less cytotoxic under a concentration of 16 μg/ml in RAW264.7 cells. The anti-inflammatory activity of MCF-F was detected using the Griess method and ELISA assay, and the results well-corroborated with the observed decrease in expression in pro-inflammatory mediators, including nitric oxide, tumor necrosis factor-α and inteleukin-1β (IL-1β). In addition, the expression of inducible NO synthase (iNOS) and cyclooxygenase2 (COX-2) were confirmed by RT-PCR and western blot, and it was found that both mRNA and protein levels were downregulated after MCF-F treatment. The data also revealed that MCF-F downregulated the phosphorylation of JNK, ERK and P38 MAPK. Collectively, these results lead to the conclusion that MCF-F exerts an anti-inflammatory effect against LPS-challenged RAW264.7 cells via the MAPK pathway.

Strengthening detoxication impacts of Coprinus comatus on nickel and fluoranthene co-contaminated soil by bacterial inoculation

To develop an efficient and environmental-friendly approach to detoxicate nickel (Ni) and fluoranthene co-contaminated soil, the combined application of Coprinus comatus (C. comatus) with Serratia sp. FFC5 and/or Enterobacter sp. E2 was investigated. The pot experiment tested the influences of bacterial inoculation on the growth of C. comatus, content of Ni in C. comatus, Ni speciation in soil, fluoranthene dissipation, soil enzymatic activities, bacterial population and community structure. With the inoculation of bacteria, the fresh weights of C. comatus, concentration of Ni in C. comatus and the dissipation rates of fluoranthene were increased by 17.73-29.38%, 68.97-204.97% and 34.84-60.90%, respectively. Notably, results illustrated that the co-inoculation of FFC5 and E2 showed better effect in biomass enhancement, Ni accumulation and fluoranthene dissipation than solitary inoculation. Simultaneously, higher soil enzymatic and microbiological activities suggested that the integrated detoxication method of bacteria and C. comatus could improve soil quality. Therefore, we can infer that bacterial inoculation strengthened detoxication effect of C. comatus in Ni-fluoranthene co-contaminated soil, indicating that the combined application of C. comatus and bacteria can be an efficient alternative for detoxicating Ni and fluoranthene co-contaminated soil.

First report of a cross-kingdom pathogenic bacterium, Achromobacter xylosoxidans isolated from stipe-rot Coprinus comatus

Coprinus comatus is an edible mushroom widely cultivated in China as a delicious food. Various diseases have occurred on C. comatus with the cultivated area increasing. In this study, the pathogenic bacterium JTG-B1, identified as Achromobacter xylosoxidans by 16S rDNA and nrdA gene sequencing, was isolated from edible mushroom Coprinus comatus with serious rot disease on its stipe. A. xylosoxidans has been confirmed as an important opportunistic human pathogenic bacterium and has been isolated from respiratory samples from cystic fibrosis. It is widely distributed in the environment. Here, we first report that fungi can also serve as a host for A. xylosoxidans. We confirmed that it can cross-kingdom infect between animals (mice) and fungi (C. comatus). The results of pathogenicity tests, physiological, biochemical and genotyping analysis of A. xylosoxidans from different hosts suggested that different strain of A. xylosoxidans may have pathogenicity differentiation. A. xylosoxidans not only is pathogenic to C. comatus but also may threaten human health.

Cytotoxic protein from the mushroom Coprinus comatus possesses a unique mode for glycan binding and specificity

Glycans possess significant chemical diversity; glycan binding proteins (GBPs) recognize specific glycans to translate their structures to functions in various physiological and pathological processes. Therefore, the discovery and characterization of novel GBPs and characterization of glycan-GBP interactions are significant to provide potential targets for therapeutic intervention of many diseases. Here, we report the biochemical, functional, and structural characterization of a 130-amino-acid protein, Y3, from the mushroom Coprinus comatus Biochemical studies of recombinant Y3 from a yeast expression system demonstrated the protein is a unique GBP. Additionally, we show that Y3 exhibits selective and potent cytotoxicity toward human T-cell leukemia Jurkat cells compared with a panel of cancer cell lines via inducing caspase-dependent apoptosis. Screening of a glycan array demonstrated GalNAcβ1-4(Fucα1-3)GlcNAc (LDNF) as a specific Y3-binding ligand. To provide a structural basis for function, the crystal structure was solved to a resolution of 1.2 Å, revealing a single-domain αβα-sandwich motif. Two monomers were dimerized to form a large 10-stranded, antiparallel β-sheet flanked by α-helices on each side, representing a unique oligomerization mode among GBPs. A large glycan binding pocket extends into the dimeric interface, and docking of LDNF identified key residues for glycan interactions. Disruption of residues predicted to be involved in LDNF/Y3 interactions resulted in the significant loss of binding to Jurkat T-cells and severely impaired their cytotoxicity. Collectively, these results demonstrate Y3 to be a GBP with selective cytotoxicity toward human T-cell leukemia cells and indicate its potential use in cancer diagnosis and treatment.

A comparative overview of antioxidative properties and phenolic profiles of different fungal origins: fruiting bodies and submerged cultures of Coprinus comatus and Coprinellus truncorum

Bioactive properties of fungi considerably differ between the fruiting body (FB) and the submerged culture as regards mycelia (M) and the fermentation broth (F). Antioxidant properties of hot-water extracts obtained from three different fungal origins: FB, M and F of two autochthonous fungal species (Northern Serbia), Coprinus comatus and Coprinellus truncorum were investigated. Free radical scavenging capacity (RSC) was evaluated in vitro by the DPPH assay and reducing power ability (FRAP assay). Considering possible bioactive properties of different compounds present in fungal extracts, the content of total proteins (TP), phenols (TC) and flavonoids (TF) were investigated colorimetrically. The chemical characterisation of the examined extracts was evaluated using the HPLC-MS/MS method. C. comatus showed the strongest RSC activity; more precisely, fermentation broth extract (FCc) on DPPH radicals (IC50 = 5.06 μg mL^-1) and fruiting body extract (FBCc) for the FRAP assay (42.86 mg ascorbic acid equivalents (AAE)/g). Submerged M extract of both species showed the highest TC (MCc 81.95 mg gallic acid eq (GAE)/g d.w.; MCt 81.64 mg GAE/g d.w.), while FB extracts contained the highest content of TP. Comparing LC-MS phenolic profiles between species-interspecifically and among different fungal origins-intraspecifically (fruiting bodies and submerged cultures), high variations were noticed. In submerged M or F extracts of C. comatus, vanillic, gallic, gentisic and cinnamic acids were detected, as opposed to FB. Considering that diverse phenolic profiles of detected antioxidant compounds were obtained by submerged cultivation, this type of cultivation is promising for the production of antioxidant substances.

Optimal Conditions for the Mycelial Growth of Coprinus comatus Strains

The principal objective of this study was to acquire basic data regarding the mycelial growth characteristics for the artificial cultivation of Coprinus comatus. 12 URP primers were employed to evaluate the genetic relationships of C. comatus, and the results were divided into three groups. Among six kinds of mushroom media, MYP medium was selected as the most favorable culture medium for C. comatus. The optimal temperature and pH ranges for the mycelial growth of C. comatus were 23~26℃ and pH 6~8, respectively. The carbon and nitrogen sources for optimal mycelial growth were sucrose and tryptone, respectively.