Search Results (85)

In this study, the molecular mechanism underlying melanin synthesis within the fermentation broth of Auricularia heimuer (A. heimuer) was explored. The absorbance at 500 nm, melanin yield, and tyrosinase activity in the fermentation broth were assessed across different fermentation durations. Mycelia samples were gathered on the 4th (R1), 8th (R2), and 10th (R3) days of liquid fermentation for transcriptome sequencing. As fermentation progressed, the absorbance, melanin yield, and tyrosinase activity in the broth rose. A total of 5915 differentially expressed genes (DEGs) were detected, with 1136 DEGs between R2 and R1, 3717 between R3 and R1, and 2950 between R3 and R2. Gene Ontology (GO) analysis showed that DEGs were significantly enriched in oxidoreductase activity and ribosome structural constituent terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed significant enrichment of DEGs in ribosome and amino acid metabolism pathways. Key DEGs, including transcription factors, glycosidases, P450 enzymes, laccases, and glutamate dehydrogenase, were identified during melanin production in the fermentation broth. These DEGs may play crucial roles in melanin synthesis. This study offers a foundation for further exploring the melanin synthesis mechanism in A. heimuer fermentation broth. Full article

Pholiota adiposa is a macrofungi that is rich in nutrients and has a delicious taste. Eating more can improve human immunity and inhibit cancer. However, the P. adiposa yield is low and cannot meet market demand. Therefore, strain improvement was carried out by exploring the mechanism of stress adaptation in P. adiposa. In addition, fermentation of the four common grains by P. adiposa mycelia increased their nutrient content and improved their antioxidant capacity. The results revealed that the growth of the mycelium was greatest when sucrose was used as the carbon source at 25 °C. At 35 °C, the MDA content and cellulase enzyme activity of the mycelia decreased by 27.6% and 40.8%, respectively, from 2 to 4 days, and the SOD, CAT, and GR enzyme activities increased by 31.6%, 49.2%, and 1.2%, respectively. The fermentation results revealed that the soluble protein content, reducing sugar content, and DPPH free radical scavenging ability of the fermented grains were significantly greater than those of the unfermented grains. This study can be used to cultivate macrofungi with environmental adaptability and provides a basis for the utilization of biological waste and increased food nutrition. Full article

Chaga (Inonotus obliquus) is an increasingly used natural product in botanical dietary supplements, valued for its bioactive compounds. However, inconsistent standardized analytical methods raise concerns over product authenticity, mislabeling, and quality control. This study employs a multi-analytical approach to differentiate wildcrafted chaga canker from North American chaga dietary supplements, particularly those containing mycelia fermented grain products. High-Performance Thin-Layer Chromatography (HPTLC), Liquid Chromatography with Evaporative Light Scattering Detection (LC-ELSD) or Photo/Diode Array Detection (LC-PDA/DAD), Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (LC-QToF-MS), Nuclear Magnetic Resonance (NMR) spectroscopy, UV-Vis spectrophotometry, and iodine-starch assays were used to evaluate key markers, including triterpenoids, polysaccharides, and melanin. Whole chaga canker contained triterpenoids (inotodiol, trametenolic acid) and phenolics, like osmundacetone, while melanin absorbance at 500 nm differentiated it from fermented grain products. β-Glucan quantification and iodine-starch assays confirmed starch-rich composition in fermented grains and its absence in authentic chaga canker. NMR fingerprinting and LC-QToF-MS metabolomics demonstrated stark compositional deviations between wildcrafted chaga canker, I. obliquus mycelium, and fermented grain products. By integrating complementary techniques, we establish a framework that can reliably distinguish genuine chaga canker from misrepresented products, ensuring consumer safety and fostering trust in the functional mushroom, canker, and mycelium markets. Full article

China is the largest strawberry producer in the world. Strawberry black root rot is a novel disease that occurs in Hohhot, Inner Mongolia. In the present study, the inhibitory effects of Bacillus subtilis S-16 and its fermented form on strawberry black root rot caused by Fusarium asiaticum were tested. The inhibition rates were 56.31% and 65.95%, respectively. Furthermore, the metabolic substances were analysed using LC-MS/MS. A total of 68 substances were identified, including 18 amino acids, 7 of which have been reported to have pro-growth and antibacterial functions. Among these seven amino acids, N-acetyl-D-alloisoleucine (NAD) had the strongest inhibitory effect on F. asiaticum. In addition, NAD caused the mycelia of F. asiaticum to appear shrivelled and deformed under electron microscopy. Furthermore, the effect of NAD on F. asiaticum was tested. The results indicate that NAD had a better prevention effect when used with hymexazol. Finally, the fungal biomass of F. asiaticum in strawberry roots was measured at different times using two treatment methods: treating plant roots with NAD and a spore suspension of F. asiaticum concurrently and with F. asiaticum alone. The colonisation response of F. asiaticum in terms of the target gene EF-1α when treated with F. asiaticum alone at 72 hpi was significantly higher than that when treated with NAD and a spore suspension of F. asiaticum. The relative expression levels of defence-related genes in strawberry roots treated with NAD at 72 hpi were determined. The genes NPR1 and PDF1 were markedly upregulated compared with other genes, suggesting that the expression of genes related to disease resistance was activated by NAD, resulting in disease resistance in strawberries. Our results provide theoretical support for the biological control of strawberry black root rot. Full article

There is increasing interest in the development of meat analogs due to growing concerns about the environmental, ethical, and health impacts of livestock production and consumption. Among non-meat protein sources, mycoproteins derived from fungal fermentation are emerging as promising meat alternatives because of their natural fibrous structure, high nutritional content, and low environmental impact. However, their poor gelling properties limit their application in creating meat analogs. This study investigated the potential of creating meat analogs by combining mycoprotein (MCP), a mycelium-based protein, with potato protein (PP), a plant-based protein, to create hybrid products with meat-like structures and textures. The PP-MCP composites were evaluated for their physicochemical, rheological, textural, and microstructural properties using electrophoresis, differential scanning calorimetry, dynamic shear rheology, texture profile analysis, confocal fluorescence microscopy, and scanning electron microscopy analyses. The PP-MCP hybrid gels were stronger and had more fibrous structures than simple PP gels, which was mainly attributed to the presence of hyphae fibers in mycelia. Dynamic shear rheology showed that the PP-MCP hybrids formed irreversible heat-set gels with a setting temperature of around 70 °C during heating, which was attributed to the unfolding and aggregation of the potato proteins. Confocal and electron microscopy analyses showed that the hybrid gels contained a network of mycelia fibers embedded within a potato protein matrix. The hardness of the PP-MCP composites could be increased by raising the potato protein content. These findings suggest that PP-MCP composites may be useful for the development of meat analogs with more meat-like structures and textures. Full article

In this study, a controlled atmosphere (CA) treatment was used in the submerged (SM) and solid-state (SS) fermentation of Inonotus obliquus to determine the optimal conditions. The goal was to accelerate the artificial fermentation to obtain I. obliquus as an ingredient for dietary supplements. The results indicated that when CA treatment was used, the SM and SS fermentation of I. obliquus yielded polysaccharide and betulinic acid contents 2–2.5 times higher than those obtained when such treatment was not used. The two fermentation methods yielded similar outcomes in terms of DPPH scavenging ability, bioactivity, and antioxidant activity. Although SS fermentation yielded highly bioactive fruiting bodies when the period of fermentation was extended to 60 days, the mycelia produced by SM reached a similar bioactivity quality with only 30 days of fermentation. It was indicated that SM fermentation is more economically feasible than SS fermentation in the production of I. obliquus. Full article

Pulse proteins are playing significant roles in the alternative protein space due to the demand for foods produced in an environmentally sustainable manner and, most importantly, due to the demand for foods of nutritious value. There has been extensive research to mimic animal-derived meat texture, flavour, mouthfeel, etc. However, there is still the perception that many of the plant-based proteins that have been texturized to mimic meat are still highly processed and contain chemicals or preservatives, reducing their appeal as being healthy and precluding any sustainable benefits. To counter this notion, the biotransformation of pulse proteins using enzymes or fermentation offers unique opportunities. Thus, this review will address the significance of pulse proteins in the alternative protein space and some of the processing aids leading to the isolation and modification of such protein concentrates in a sustainable manner. Fermentation-based valorization of pulse proteins will also be discussed as a “clean label” strategy (further adding to sustainable nutritious plant protein production), although some of the processes like the extensive use of water in submerged fermentation need to be addressed. Full article

Aspergillus cristatus is a crucial edible fungus used in tea fermentation. In the industrial fermentation process, the fungus experiences a low to high osmotic pressure environment. To explore the law of material metabolism changes during osmotic pressure changes, NaCl was used here to construct different osmotic pressure environments. Liquid chromatography–mass spectrometry (LC–MS) combined with multivariate analysis was performed to analyze the distribution and composition of A. cristatus under different salt concentrations. At the same time, the in vitro antioxidant activity was evaluated. The LC–MS metabolomics analysis revealed significant differences between three A. cristatus mycelium samples grown on media with and without NaCl concentrations of 8% and 18%. The contents of gibberellin A3, A124, and prostaglandin A2 related to mycelial growth and those of arabitol and fructose-1,6-diphosphate related to osmotic pressure regulation were significantly reduced at high NaCl concentrations. The biosynthesis of energy-related pantothenol and pantothenic acid and antagonism-related fluvastatin, aflatoxin, and alternariol significantly increased at high NaCl concentrations. Several antioxidant capacities of A. cristatus mycelia were directly related to osmotic pressure and exhibited a significant downward trend with an increase in environmental osmotic pressure. The aforementioned results indicate that A. cristatus adapts to changes in salt concentration by adjusting their metabolite synthesis. At the same time, a unique set of strategies was developed to cope with high salt stress, including growth restriction, osmotic pressure balance, oxidative stress response, antioxidant defense, and survival competition. Full article

Hericium erinaceus has long been favored for its remarkable nutritional and health-promoting benefits, and erinacine A is the key component responsible for the neuroprotective properties of H. erinaceus. Establishing an efficient method for separating erinacine A from H. erinaceus and screening the erinacine A-enriched strains is crucial to maximizing its benefits. Herein, we first reported that high-speed counter current chromatography (HSCCC) is an effective method for separating high-purity erinacine A. Using a two-phase solvent system composed of n-hexane/ethyl acetate/methanol/water (4.5:5:4.5:5, v/v/v/v), erinacine A with a purity of over 95% was separated. Then, we evaluated the content and yield of erinacine A in the liquid-fermented mycelia of Hericium germplasms. Both the content and yield of erinacine A varied greatly among the surveyed strains. The significant effect of the strain on the erinacine A content and yield was revealed by an analysis of variance. The highest erinacine A content and yield were observed in the mycelia of a wild strain HeG, reaching 42.16 mg/g and 358.78 mg/L, which is superior to the current highest outcomes achieved using submerged cultivation. The isolation method established and the strains screened in this study can be beneficial for the scaling up of erinacine A extraction and nutraceutical development to industrial levels. Full article

Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm mushrooms are cultivated on diverse by-products based on substrates that hold promise for mitigating antibiotic usage in the poultry industry and reducing environmental pollution. By incorporating agricultural by-products into mushroom cultivation, the functionality of the mushroom products can be increased, then the final product can be a more effective feed supplement. After mushroom cultivation, spent mushroom substrate (SMS) can be valorized, due to the presence of huge amounts of bioactive compounds like β-glucan, chitin, polyphenols, and flavonoids related to mycelia. As a prebiotic and antimicrobial feed supplement, these mushrooms positively influence gut microbiota, intestinal morphology, and thus overall poultry well-being. This article underscores the potential of solid-state fermentation (SSF) to enhance the bioactivity of oyster mushrooms and their derivatives, offering a cost-effective and efficient strategy for transforming unconventional feeding materials. Moreover, it emphasizes broader implications, including the reduction of antibiotic dependence in poultry farming, highlighting the promising integration of oyster mushrooms and their derivatives for sustainable and environmentally conscious poultry production. Full article

Corticosteroids are commonly used anti-inflammatory agents. However, their prolonged use can lead to side effects. Therefore, the development of natural compounds with minimal side effects is necessary. This study was performed to investigate the anti-inflammatory effects and mechanisms of action of Chamaecyparis obtusa (Siebold & Zucc.) Endl. leaf (COL), bioconverted using Ganoderma applanatum (G. applanatum) in lipopolysaccharide (LPS)-induced RAW264.7 cells. The COL 70% EtOH extract fermented by G. applanatum (70COLGA) improved the high cytotoxicity of 70% EtOH extracts (70COL). When RAW264.7 cells were pre-treated with 100 and 200 μg/mL of 70COLGA for 2 h and then treated with LPS for 16 h, LPS induced the production of nitric oxide (NO), and the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) were significantly inhibited. When RAW264.7 cells were pre-treated with 100 and 200 μg/mL of 70COLGA for 2 h and then treated with LPS for 4 h, the phosphorylation of signal transducers and activators of transcription (STAT) was markedly decreased. In addition, 70COLGA markedly suppressed the production of the inflammatory cytokines interleukin (IL)-1β and IL-6 in LPS-induced RAW264.7 cells. Analysis of pro-inflammatory molecules using cytokine arrays showed that macrophage inflammatory protein (MIP)-2, granulocyte–macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF) and IL-27 expressions were also suppressed by 200 μg/mL of 70COLGA in LPS-induced RAW264.7 cells. These results demonstrate that 70COLGA significantly prevented inflammatory responses by inhibiting the secretion of pro-inflammatory molecules in LPS-induced RAW264.7 cells. When RAW264.7 cells were pre-treated with 100 and 200 μg/mL of 70COLGA for 2 h and then treated with LPS-conditioned medium (LPS-CM) for 30 min, 70COLGA directly inhibited STAT activation. In summary, our findings suggest that 70COLGA has therapeutic potential for the treatment of inflammatory diseases. Full article

Trametes lactinea is a macrofungus commonly found on broadleaf tree felling piles with rich bioactivity, and its main active substances are polysaccharides, which have a certain medicinal value. Few studies have been conducted on the simultaneous study of intracellular and extracellular polysaccharides of fermented mycelia in liquid culture. In this study, T. lactinea collected from Eucalyptus stumps was subjected to liquid fermentation culturing and the extraction of intracellular and extracellular polysaccharides from the mycelium was optimized using unidirectional and orthogonal test methods. The intracellular and extracellular crude polysaccharides were isolated and purified, and polysaccharide fractions were obtained and assayed for their chemical composition. The main findings of this study are as follows: (1) The optimal conditions for the extraction of intracellular polysaccharides from T. lactinea mycelium were a material–liquid ratio of 1:40, an extraction temperature of 100 °C, a time of 5 h, and four repeats, wherein the polysaccharide extraction rate reached 5.1%. The optimal extraction conditions for the extracellular polysaccharides were a concentration ratio of 5:1, a concentration temperature of 70 °C, an ethanol concentration of 100.0%, and an alcohol settling time of 12 h. The polysaccharides could thus be extracted up to 0.63 mg/mL. (2) The intracellular and extracellular crude polysaccharides of T. lactinea mycelium were successfully isolated and purified, resulting in three homogeneous fractions of intracellular polysaccharides (IP-1, IP-2, and IP-3) and two homogeneous fractions of extracellular polysaccharides (EP-1 and EP-2). (3) The polysaccharide chemical composition resulted in the highest total sugar content of EP-1. IP-3 had the highest uronic acid content. The results of the monosaccharide composition analysis showed that the mycelial intracellular polysaccharides IP-1, IP-2, and IP-3 were all highest in glucose. Both IP-2 and IP-3 contained guluronic acid and glucuronic acid. Mannose was the most abundant extracellular polysaccharide in both EP-1 and EP-2. This study provides theoretical and technical bases for the comprehensive development and utilization of T. lactinea polysaccharides. Full article

Polysaccharides and protein–polysaccharide complexes produced from the fungal strain Trametes versicolor have demonstrated bioactive properties that depend on the substrate, the fermentation conditions and also the fungal strain. Likewise, the submerged and controlled fermentation of medicinal mushrooms elicits numerous advantages over traditional processes to produce mycelia and added-value products, along with the exploitation of biodiversity. This study evaluated the growth profile of an indigenous T. versicolor isolate using commercial nutrients that were subsequently replaced with renewable resources, specifically, grape pomace extract (GPE), under static and shaking conditions. The effect of elicitor addition was also assessed using GPE. The process productivity was significantly improved, yielding 21 g/L of biomass. Agitation proved beneficial for all examined cases regarding biomass productivity and substrate consumption rates. The chemical and antioxidant profile of crude intracellular and extracellular polysaccharides was determined, whereby intracellular extracts indicated >50% antioxidant activity. FTIR analysis validated the preliminary chemical characterization of the extracts, whereas the amino acid profile of IPS extracts was also included. Evidently, our study elaborates on the development of a bioconversion concept to valorize wine-making side-streams to formulate added-value products with potential bioactive attributes. Full article

Antrodia cinnamomea (AC), a rare fungus endemic to Taiwan, contains high levels of various secondary metabolites, notably triterpenoids, having useful medicinal and pharmacological properties. Techniques for increasing the production of AC triterpenoids (ACT) for medicinal purposes are a high research priority. We measured and compared the biomass and ACT content of AC mycelia under various liquid fermentation culture conditions. Relative gene expression levels of ten enzymes involved in the mevalonate (MVA) pathway and “subsequent group modification pathway” were determined, and correlation analysis was performed to evaluate the roles of these enzyme genes in ACT synthesis. Two representative genes encoding the enzymes lanosterol synthase (AcLSS) and sterol C-24 reductase (AcERG4), whose activity is closely associated with ACT content, were selected for homologous expression. AcLSS and AcERG4 were separately linked to plasmid pCT74, and transformed into prepared AC protoplasts to obtain two recombinant strains, termed RpLSS and RpERG4, by polyethylene glycol (PEG)-CaCl2-mediated protoplast transformation. Upregulated expression levels of AcLSS and AcERG4 (1.78- and 1.41-fold, respectively) were associated with significantly higher (1.82- and 1.37-fold, respectively) ACT content in the recombinant strains in comparison with the wild-type. Our findings provide a theoretical and practical basis for the enhancement of ACT production using homologous expression techniques. Full article

Selenium (Se) is a trace element that plays a crucial role in metabolism; a lack of selenium reduces the body’s resistance and immunity, as well as causes other physiological problems. In this study, we aim to identify favorable conditions for improving organic selenium production. The functional microbe Monascus purpureus, which is widely used in food production, was employed to optimize selenium-enriched culture conditions, and its growth mode and selenium-enriched features were investigated. Spectrophotometry, inductively coupled plasma optical emission spectrometry (ICP-OES), and HPLC (High-Performance Liquid Chromatography) were used to determine the effects of various doses of sodium selenite on the selenium content, growth, and metabolism of M. purpureus, as well as the conversion rate of organic selenium. The best culture parameters for selenium-rich M. purpureus included 7.5 mg/100 mL of selenium content in the culture medium, a pH value of 6.8, a culture temperature of 30 °C, and a rotation speed of 180 rpm. Under ideal circumstances, the mycelia had a maximum selenium concentration of approximately 239.17 mg/kg, with organic selenium accounting for 93.45%, monacoline K production reaching 70.264 mg/L, and a secondary utilization rate of external selenium of 22.99%. This study revealed a novel biological route—selenium-rich M. purpureus fermentation—for converting inorganic selenium into organic selenium. Full article