Transcriptome analysis of Auricularia fibrillifera fruit-body responses to drought stress and rehydration

Background Drought stress severely restricts edible fungus production. The genus Auricularia has a rare drought tolerance, a rehydration capability, and is nutrient rich. Results The key genes and metabolic pathways involved in drought-stress and rehydration were investigated using a transcriptome analysis to clarify the relevant molecular mechanisms. In total, 173.93 Mb clean reads, 26.09 Gb of data bulk, and 52,954 unigenes were obtained. Under drought-stress and rehydration conditions, 14,235 and 8539 differentially expressed genes, respectively, were detected. ‘Tyrosine metabolic’, ‘caffeine metabolism’, ‘ribosome’, ‘phagosome’, and ‘proline and arginine metabolism’, as well as ‘peroxisome’ and ‘mitogen-activated protein kinase signaling’ pathways, had major roles in A. fibrillifera responses to drought stress. ‘Tyrosine’ and ‘caffeine metabolism’ might reveal unknown mechanisms for the antioxidation of A. fibrillifera under drought-stress conditions. During the rehydration process, ‘diterpenoid biosynthesis’, ‘butanoate metabolism’, ‘C5-branched dibasic acid’, and ‘aflatoxin biosynthesis’ pathways were significantly enriched. Gibberellins and γ-aminobutyric acid were important in the recovery of A. fibrillifera growth after rehydration. Many genes related to antibiotics, vitamins, and other health-related ingredients were found in A. fibrillifera. Conclusion These findings suggested that the candidate genes and metabolites involved in crucial biological pathways might regulate the drought tolerance or rehydration of Auricularia, shedding light on the corresponding mechanisms and providing new potential targets for the breeding and cultivation of drought-tolerant fungi.

High Throughput Identification of the Potential Antioxidant Peptides in Ophiocordyceps sinensis

Ophiocordyceps sinensis, an ascomycete caterpillar fungus, has been used as a Traditional Chinese Medicine owing to its bioactive properties. However, until now the bio-active peptides have not been identified in this fungus. Here, the raw RNA sequences of three crucial growth stages of the artificially cultivated O. sinensis and the wild-grown mature fruit-body were aligned to the genome of O. sinensis. Both homology-based prediction and de novo-based prediction methods were used to identify 8541 putative antioxidant peptides (pAOPs). The expression profiles of the cultivated mature fruiting body were similar to those found in the wild specimens. The differential expression of 1008 pAOPs matched genes had the highest difference between ST and MF, suggesting that the pAOPs were primarily induced and play important roles in the process of the fruit-body maturation. Gene ontology analysis showed that most of pAOPs matched genes were enriched in terms of ‘cell redox homeostasis’, ‘response to oxidative stresses’, ‘catalase activity’, and ‘ integral component of cell membrane’. A total of 1655 pAOPs was identified in our protein-seqs, and some crucial pAOPs were selected, including catalase, peroxiredoxin, and SOD [Cu–Zn]. Our findings offer the first identification of the active peptide ingredients in O. sinensis, facilitating the discovery of anti-infectious bio-activity and the understanding of the roles of AOPs in fungal pathogenicity and the high-altitude adaptation in this medicinal fungus.

Effect of packaging materials on the quality of oyster mushrooms (Pleurotus saijo caju) during storage

The study aims to investigate the optimal packaging material to maximise the restriction of physiological and biochemical changes which reduce oyster mushroom (Pleurotus saijo caju) quality during the storage after harvesting. There are six packaging techniques tested, including PET box, PET box with kraft paper, PET box with kraft covered by GreenMAP bag, soft tray covered GreenMAP bag, soft tray with kraft paper in GreenMAP bag, and kraft paper. The result shows that the PET box with kraft paper in the GreenMAP bag is the most suitable for the storage of oyster mushrooms. After 10 days under 4oC, the lowest weight reduction can be seen with only 5.78%, soluble protein declines 65.49%, and decrease of vitamin C with 27.87 mg/100 g. In addition, the fruit body can maintain the colour, structure, and taste better than those packed with other materials

Nephroprotective and antioxidant effects of ethanol extract of Coprinus comatus mushroom fruit-bodies on streptozotocin-induced diabetic rat models

Diabetes mellitus (DM) is a metabolic disease with an increasing prevalence. An increase in free radicals and AGEs can cause glomerular cell damage which can lead to inflammation and DM nephropathy. WHO has recommended DM treatment by using herbal medicines that have minimal side effects and have a lot of biological activity to prevent complications. Coprinus comatus (O.F. Mull.) is known as immunomodulatory, anti-inflammatory and antidiabetic agent. The research used C. comatus cultivated in Cianjur. The basidiome of this mushroom has slightly oval and small with height of 8-12 cm and thickness of 2-3 cm. The research included six groups of male Wistar rats: Group 1 received no treatment, Groups 2–6 were administered 45 mg/kg BW streptozotocin once, Group 3 was administered 45 mg/kg BW metformin, Groups 4, 5, and 6 were administered 250, 500, and 750 mg/kg BW of C. comatus fruit body ethanol extract respectively for 14 days. The superoxide dismutase (SOD), malondialdehyde (MDA), hepcidin and β2 microglobulin (B2M) levels were evaluated. Data were analyzed using analysis of variance and Duncan’s multiple-range tests. The results showed that dose of 500 mg was effective in increasing SOD and decreasing hepcidin, B2M and MDA levels.

Studying on cytotoxic activity of ethyl acetate extracts and isolated substances from cultured Isaria cicadae F0004 in Vietnam against the MCF-7 cell lines and Jurkat cell lines

Isaria cicadae species of the Isaria genus have been isolated in many Asian countries, including China, Korea, Thailand, and Vietnam. Furthermore, Isaria cicadae content potential medicinal source in the prevention and treatment of cancer, strengthening the immune system. This study aims to investigate the cytotoxicity against MCF-7 and Jurkat T cell lines of the extract and isolated potential compounds from Isaria cicadae in Vietnam. The results showed that ethyl acetate (EA) extract from the fruit body of the Isaria cicadae F0004 strain had high cytotoxic activity against both MCF-7 and Jurkat cell lines at the concentration of 100 μg/mL with the IC50 value was reached 17.15 ± 1.68 and 10.37 ± 0.61 μg/mL respectively. The constituents of the EA extract from the fungus Isaria cicadae F0004 were isolated by column chromatography and preparative chromatography. Then, the structures were determined by spectroscopy 1H-NMR, 13C-NMR. It was obtained 5 compounds including uracil, 1-0-ethyl-ß-D-ribofuranose, ergosterol, p-hydroxybenzoic acid, protocatechuic acid. Protocatechuic acid isolated from Isaria cicadae F0004 that showed cytotoxic activity on MCF-7 and Jurkat cell lines with IC50 values of 5.97 ± 0.36 and 3.15 ± 0.64 (mM) respectively. This study is the basis for further research on the cytotoxic activity of the fungus Isaria cicadae F0004 in vitro.

Cultivation of mycelium of the edible fungus Pleurotus ostreatus (oyster mushroom) with the use of wet sparging grain, the waste of the brewing industry.

Wet sparging grain, a waste product of brewery, was shown to be successfully utilized as a supplement to the nutrient media and substrates for both isolation of the vegetative mycelium of the Pleurotus ostreatus mushroom, as well as for its further recovery and growing the carposomes. We studied the influence of the wet sparging grain on mycelium growth. Cultivation results demonstrated that wet sparging grain is an efficient additional component to the minimal agarized nutrient media for P. ostreatus growth and isolation and to its common fruit body cultivation substrates. Even the depleted agaric media and substrates with addition of the sparging grain allowed intensive growth of the P. ostreatus mycelium and its fructifying. Practical Application: Addition of wet sparging grain to poor cheap substrates increases their quality for rearing the edible oyster mushroom mycelium to the level of reach substrates, and allows utilization of agricultural wastes. The technique is ready for application and patented in the Russian Federation.

Biomass and Cordycepin Production by the Medicinal Mushroom Cordyceps militaris—A Review of Various Aspects and Recent Trends towards the Exploitation of a Valuable Fungus

Cordyceps militaris is an entomopathogenic ascomycete with similar pharmacological importance to that of the wild caterpillar fungus Ophiocordyceps sinensis. C. militaris has attracted significant research and commercial interest due to its content in bioactive compounds beneficial to human health and the relative ease of cultivation under laboratory conditions. However, room for improvement exists in the commercial-scale cultivation of C. militaris and concerns issues principally related to appropriate strain selection, genetic degeneration of cultures, and substrate optimization. In particular, culture degeneration—usually expressed by abnormal fruit body formation and reduced sporulation—results in important economic losses and is holding back investors and potential growers (mainly in Western countries) from further developing this highly promising sector. In the present review, the main factors that influence the generation of biomass and metabolites (with emphasis on cordycepin biosynthesis) by C. militaris are presented and evaluated in conjunction with the use of a wide range of supplements or additives towards the enhancement of fungal productivity in large-scale cultivation processes. Moreover, physiological and genetic factors that increase or reduce the manifestation of strain degeneration in C. militaris are outlined. Finally, methodologies for developing protocols to be used in C. militaris functional biology studies are discussed.

Artificial cultivation of a novel wild strain of Lepista sordida (Sowerby) Pat from south west China

A novel wild strain of Lepista sordida mushroom was collected from a soybean field in Liujiaba at Dazhou district of south western area of China in 2015.The morphological description and molecular identification were conducted to confirm the species. In the present study, optimization was carried out from mycelial growth and fruit body production. For DAAS-E70, the best growth rate was obtained using yeast malt extract, pH 6.0 and temperature 25°C. The wheat grain mushroom spawn was used for upscaling of the mycelium to be used for fruiting body production. In the field experiments, the average biological efficiency of DAAS-E70 was higher than that of Jilin-1, in which, DAAS-E70 accounting for 41.22% of the average biological efficiency, while the Jilin-1 was 35.02%. The stable biological efficiency of DAAS-E70 in different environments and seasons showed that the DAAS-E70 could be used for its commercial cultivation and could provide a new reference for its artificial domestication. Bangladesh J. Bot. 50(3): 813-818, 2021 (September) Special

ISOLATION, PHYSICO-CHEMICAL CHARACTERISTICS OF POLYSACCHARIDE ISOLATED FROM THE FRUIT BODY OF INONOTUS HISPIDUS

The article is devoted to the study of polysaccharides isolated from the basidiomycete raw material I. hispidus and studying their physical and chemical properties. Water-soluble polysaccharides were isolated from mushroom raw materials by the method of sequential water extraction and the yield was 9.44%. Polysaccharides were separated into neutral fractions by ion exchange chromatography and purified from proteins and peptides. During the separation process, it was determined that the polysaccharide sample consisted of homogeneous polysaccharides, while the carbohydrate content of the purified polysaccharide sample was 99.4%. The carbohydrate composition of polysaccharides was determined, it was found that the polysaccharide consists mainly of glucose residues and contains minor amounts of fructose and rhamnose residues. Molecular weight and molecular weight distribution were determined by size exclusion chromatography. The Mw of the polysaccharide sample obtained was 18.7 kDa, the polydispersity index was 1.3. The results of IR-, 1H- and 13C NMR spectroscopic studies have shown that the polysaccharide, according to its structural characteristics, belongs to the β-glucan type polysaccharide having β-(1,3) and β-(1,6)-glycosidic bounds.

Biomass production of fungus \(\textit{Termitomyces clypeatus}\) in a stirred-tank bioreactor

Termitomyces clypeatus is a fungus species, which has been used as food and medicinal mushroom. In the current study, submersed fermentation of the fungus in a stirred-tank bioreactor was determined for its culture biomass and nutrient contents. T. clypeatus obtained its highest biomass after from 13 to 15 days of cultivation, when the dry biomass of its mycelium system was more than 6%. Agitation speeds of 150 or 180 rpm were the most suitable for the fungus. The determination of chemical compositions showed that the dry biomass of its mycelium system had high protein content, with 57.8% on its dry-weight basis. Besides, 11 types of amino acids higher than 0.1% of wet weight culture were found in fermentation products. Moreover, dried mycelia of the fungus contained 27.4% carbohydrates. The protein and carbohydrate containing in the mycelium and fruit body of T. clypeatus were not statistically different. These results showed that a stirred-tank bioreactor could be applied to culture the fungus.