Search Results (620)

Corn is one of the most widely cultivated cereal crops and is rich in antioxidant compounds, especially phenolics. However, many of these are bound to cell wall components, requiring pre-treatment for release. Solid-state fermentation (SSF) with Rhizopus oryzae has been used to enhance antioxidant capacity in grains and legumes, though its application in pigmented corn (PC) has not been reported. This study evaluated R. oryzae growth on PC via SSF and its effect on phenolic compound release and antioxidant capacity (AC). Variables such as temperature, pH, inoculum, and medium salts were tested for their influence on phenolic release and AC. Nutrient changes in PC due to SSF were also examined. HPLC-MS was used to analyze the phenolic compounds’ profile. R. oryzae grew effectively on PC, increasing total phenolic content (TPC) and AC by 131 and 50%, respectively. The pH was found to negatively impact phenolic release. The SSF also raised protein content by 10% and reduced carbohydrates and fiber by 3 and 8%. Thirteen phenolic compounds were identified, including Feruloyl tartaric acid ester and p-Coumaroyl tartaric acid glycosidic ester, with known anti-inflammatory properties. This process offers a sustainable method for enhancing the functional properties of pigmented corn. Full article

This study aimed to isolate and identify fungi capable of producing xylanases and cellulases. Thirty-eight fungal strains were isolated from decaying water hyacinth (WH), and two were selected based on their superior enzyme production under solid-state fermentation (SSF). The strains were identified through morphological, cultural, and molecular analyses as Aspergillus austwickii B6 and Trichoderma harzianum M7. Their ribosomal ITS sequences were deposited in GenBank under accession numbers PQ142799.1 for A. austwickii B6 and PQ007458.1 for T. harzianum M7. Enzyme production was evaluated under SSF using eight culture medium variants prepared with natural or pretreated biomasses of WH and sugarcane bagasse (SCB), combined with either NaNO₃ or (NH₄)₂SO₄ as nitrogen sources. The maximum xylanase and cellulase activities were 752 and 65 U/g dry matter (DM), respectively, for A. austwickii B6, and 1724 and 152 U/g DM for T. harzianum M7, when cultivated on a low-cost medium composed of pretreated WH, (NH₄)₂SO₄, and a simple mineral salt solution. These findings highlight the potential of locally isolated fungal strains and lignocellulosic residues as cost-effective substrates and inducers of xylanase and cellulase production under SSF and underscore the importance of WH pretreatment to enhance substrate availability and maximize enzyme yields. Full article

Cordyceps militaris (C. militaris) is a medicinal fungus renowned for its diverse therapeutic properties, largely attributed to bioactive compounds such as cordycepin, polysaccharides, adenosine, D-mannitol, carotenoids, and ergosterol. However, the production and composition of these metabolites are highly influenced by cultivation conditions, highlighting the need for systematic optimization strategies. This review synthesizes current findings on how nutritional factors—including carbon and nitrogen sources, their ratios, and trace elements—and environmental parameters such as oxygen availability, pH, temperature, and light regulate C. militaris metabolite biosynthesis. The impacts of solid-state fermentation (using grains, insects, and agro-industrial residues) and liquid state fermentation (submerged and surface cultures) are compared, with attention to their roles in mycelial growth, fruiting body formation, and secondary metabolite production. Special emphasis is placed on mixed grain–insect substrates and light regulation, which have emerged as promising methods to enhance cordycepin accumulation. Beyond summarizing advances, this review also identifies key knowledge gaps that must be addressed: (i) the incomplete understanding of metabolite regulatory networks, (ii) the absence of standardized cultivation protocols, and (iii) unresolved challenges in scale-up, including oxygen transfer, foam control, and downstream processing. We propose that future research should integrate multi-omics approaches with bioprocess engineering to overcome these limitations. Collectively, this review highlights both current progress and remaining challenges, providing a roadmap for advancing the sustainable, scalable, and application-driven production of bioactive compounds from C. militaris. Full article

The growing demand for aquaculture has driven the search for sustainable practices and utilization of agro-industrial residues. Brown rice bran, an abundant and low-cost by-product, has emerged as a promising raw material. This dissertation aimed to evaluate solid-state fermentation (SSF) of rice bran using the fungus Rhizopus oryzae and the yeast Saccharomyces cerevisiae with the goal of improving its nutritional value for use in diets formulated for zebrafish (Danio rerio). Proximate composition analyses revealed the strong biotransformation potential of Rhizopus oryzae. Fermentation with this fungus resulted in a significant 36.45% increase in protein content, a 51.62% increase in total polyphenols, and a 13.7% reduction in lipid content. In an in vivo experiment, zebrafish fed a diet containing rice bran fermented by R. oryzae showed the best zootechnical performance, with higher weight gain, specific growth rate, and improved feed conversion. Gene expression analysis showed a significant difference only for glut6, which is related to glucose transport. In summary, the fermentation of brown rice bran with Rhizopus oryzae represents an effective strategy to enhance its nutritional profile, establishing it as a viable alternative for the formulation of more sustainable and efficient diets in aquaculture. Full article

A significant quantity of agro-industrial waste is generated globally across various agricultural sectors and food industries. Composed primarily of cellulose, hemicellulose, and lignin—known as lignocellulosic materials—this waste holds significant potential and can be repurposed as a nutrient-rich substrate for mushroom cultivation. Therefore, mushroom cultivation can be regarded as a promising biotechnological approach for the reduction and valorization of agro-industrial waste. This investigation is the first to explore the utilization of agro-industrial waste- and by-products for the cultivation of Epicoccum nigrum for the production of extracts with valuable biological activities. The logistic curve and autocatalytic growth models were applied to study the kinetics of the growth process on wheat bran, sunflower cake, wheat straw, pine sawdust, and steam-distilled lavender straw substrates. Through mathematical modeling, the optimal composition of a nutrient medium containing the selected substrates was determined and successfully validated in experimental conditions. Biologically active water extracts were obtained after solid-state cultivation with α-amylase and cellulase activity up to 10.6 ± 0.6 U/mL and 0.52 ± 0.03 U/g, respectively. The extracts exhibited antimicrobial activity against fungal strains from six different species, and the most susceptible was the phytopathogen Sclerotinia sclerotiorum, with a minimum inhibitory concentration of 0.156–0.313 mg/mL. Full article

This study explores the production of nutritious edible mushrooms from mixtures of agave bagasse, an abundant agroindustrial byproduct, through the biotechnological application of solid-state fermentation using the edible mushroom Pleurotus djamor. The ability of the fungus to biotransform different mixtures of agave bagasse and corn stover into secondary metabolites of nutraceutical interest, such as polyphenols, organic acids, and bioactive polysaccharides, was evaluated. Biological efficiency (BE), morphological change, texture, and antioxidant capacity were also assessed, correlating the results with the impact of substrates and fungal developmental stages. The color, size, and margin of P. djamor basidiomas were observed to vary among treatments; BE progressively decreased from T0 (106.5%) to T4 (33.16%). Treatments with higher amounts of agave bagasse (T4) generated firmer fungi, with a fracture toughness of 7.06 ± 3.06 newtons. During fungal development, phenols, flavonoids, and tannins fluctuated. Treatment T0 showed the highest concentration of phenols (5.41 ± 0.92 mg GAE g⁻¹). Treatment T4 stood out for its high antioxidant capacity (DPPH) (61.83 ± 12.16% inhibition). Finally, 17 non-phenolic secondary metabolites were found: L-valine, L-leucine, L-isoleucine, L, D-phenylalanine, L-proline, alanine, L-asparagine, serine, glutamic acid, linoleic acid, palmitic acid, butanoic acid, propanoic acid, pyrimidine, succinic acid, hexanedioic acid, and phosphoric acid. In conclusion, P. djamor can biotransform agroindustrial waste into edible fungi containing nutraceutical compounds. Full article

This study presents an integrated valorization strategy for oat husks through microwave-assisted pretreatment using a deep eutectic solvent (DES) composed of choline chloride and glycerol (1:2). The process was designed to enhance the release of fermentable sugars, enable xylooligosaccharide (XOS) production, and support inulinase production by Aspergillus niger A42 via submerged fermentation of the hydrolysate and solid-state fermentation of the residual biomass. Response surface methodology (RSM) was applied to evaluate the effects of microwave power, treatment time, and liquid-to-solid ratio (LSR) on fermentable sugar content (FSC) and total phenolic compounds (TPCs). Following pretreatment, the biomass was hydrolyzed using 1.99% sulfuric acid for 1 min. Optimal pretreatment conditions (350 W, 30 s, LSR 4 w/w) yielded an FSC of 51.14 g/L. Additionally, 230.78 mg/L xylohexaose and 6.47 mg/L xylotetraose were detected. Submerged fermentation of the liquid fraction with A. niger A42 resulted in inulinase and invertase activities of 60.45 U/mL and 21.83 U/mL, respectively. Solid-state fermentation of the pretreated solids produced 37.03 U/mL inulinase and 17.64 U/mL invertase. The integration of microwave-assisted DES pretreatment, dilute acid hydrolysis, and fungal fermentation established a robust strategy for the sequential production of XOS, fermentable sugars, and inulinase from oat husks, supporting their comprehensive utilization within a sustainable biorefinery framework. Full article

Proteases (EC 3.4) are hydrolytic enzymes widely used in biotechnological processes, representing about 60 to 70% of the global industrial enzyme market. Edible mushrooms of the genus Pleurotus stand out as excellent producers of these enzymes, in addition to exhibiting high nutritional value and medicinal properties. The proteases produced by these species exhibit broad adaptability to different experimental conditions, including variations in optimal pH and temperature, as well as distinct sensitivities to inhibitors. The production of these enzymes can be intensified by solid-state fermentation (SSF) using low-cost agro-industrial substrates, such as wheat bran, which favors sustainable applications aligned with the circular economy. Parameters such as carbon/nitrogen (C/N) ratio, medium pH, cultivation time, and inoculum age directly influence enzyme productivity. Proteases from Pleurotus spp. show high potential in the biochemical control of parasites such as Meloidogyne incognita, Haemonchus spp., Taenia solium, and Moniezia sp., catalyzing the degradation of the cuticle or eggshell. Other biotechnological applications include milk coagulation, thrombolytic therapies, keratin bioconversion, increased protein digestibility, and use as additives in the food, detergent, and pharmaceutical industries. Full article

This study addressed the challenges posed by wet-grade maize distiller’s dried grains with solubles (DDGS), which are characterized by high moisture and complex fibers that limit their storage and utilization in poultry feed. Three experiments were conducted to enhance their nutritional value through enzymatic and solid-state fermentation treatments. In vitro pre-digestion using multiple enzymes significantly improved dry matter solubility (DMS) and reducing sugar yield for maize DDGS and the ingredient maize germ meal (MGM). Using optimized parameters, wet-based DDGS-MGM was subjected to solid-state fermentation with 500 mg/kg of cellulase and 200 mg/kg of the X1 enzyme (a laboratory-developed multi-enzyme complex), and this treatment enhanced both DMS and reducing sugar yield, and the resulting fermented product was subsequently applied in further experiments. In the broiler trial, forty 22-day-old Arbor Acres broilers with similar body weights were randomly assigned to five treatment groups, including the control group, (50% DDGS + 50% MGM) unfermented group, (62.5% DDGS + 37.5% MGM) unfermented group, (50% DDGS + 50% MGM) fermented group, and (62.5% DDGS + 37.5% MGM) fermented group, with eight replicates per treatment (one broiler per replicate). Replacement of 30% of the basal diet with fermented 50:50 DDGS-MGM material significantly increased apparent metabolizable energy (AME) and nitrogen-corrected AME by 2.74 MJ/kg and 2.73 MJ/kg, respectively, corresponding to improvements of 39.60% and 40.81% compared to the unfermented control (p < 0.05). Economic analysis indicated that using 5% fermented DDGS-MGM in feed reduced cost by 20.45 RMB per metric ton. These findings demonstrate that bioprocessing can improve the utilization and economic value of maize processing by-products, although further validation under practical conditions is needed. Full article

As the core of the solid-state fermentation system, the quality of pit mud is directly determined by the synergistic effects of volatile flavor compounds, microbial communities, and abiotic physicochemical factors. However, pit mud lacks systematic knowledge, especially concerning the dynamic association mechanism and threshold effect of its three components. This results in blind spots within the pit mud metabolism regulation network, which has become a bottleneck in precise pit mud quality regulation. Focusing on the volatile flavor compounds of pit mud is crucial to exploring their association with the core microbial community and physicochemical factors of pit mud, in order to cultivate high-quality pit mud. Although a large number of studies have revealed the formation mechanism of high-quality pit mud based on the three factors and cultivated artificial pit mud through microbial enhancement or synthetic flora to improve the quality. However, anaerobic fermentation is a complex system, and the complexity and dynamics of microorganisms make it difficult for biofortification and synthetic flora to effectively regulate the quality of pit mud. Therefore, this paper reviews the research progress on flavor compounds, microbial communities and abiotic factors associated with pit mud quality, deepens the understanding of their influence on pit mud quality, and proposes a precise environmental control strategy to alter the composition and content of the microbial community in the pit mud. The key to this scheme lies in constructing a correlation network through multi-omics integration to identify the physical and chemical factors related to the quality of the pit mud. During the fermentation process, intervention measures are taken on environmental parameters, ultimately effectively changing the physical and chemical factors, thereby achieving the assumption of precise control of the quality of the pit mud. This provides necessary references and inspirations for improving the quality of pit mud, cultivating artificial cellar mud, and enhancing the quality of Baijiu. Full article

Gossypol, a polyphenolic naphthalene derivative and yellow polyphenolic pigment found in cotton seed glands, presents notable environmental, animal, and human health hazards. To screen for yeast strains capable of utilizing gossypol and to investigate their removal efficiency and mechanisms. Yeast strains capable of utilizing gossypol as the exclusive carbon source were isolated from cotton field soil. The identification of these strains involved assessment of colony morphology, physiological and biochemical characteristics, and phylogenetic analysis utilizing 26S rDNA gene sequences. Safety evaluations included hemolytic and antibiotic susceptibility tests. The growth responses of the selected strains to varying temperatures and pH levels were determined. Using cotton meal as the solid fermentation substrate, the effects of single factors on gossypol removal by the strains were determined. The intracellular and extracellular localization as well as the nature of the gossypol-removing active components in the strains were characterized, followed by an investigation into the molecular mechanism of gossypol removal using LC-MS analysis. A total of 17 gossypol-utilizing strains were isolated from cotton field soil samples, with strain ZYS-3 demonstrating superior removal capability. Strain ZYS-3 was identified as Meyerozyma guilliermondii, exhibiting no hemolytic activity and susceptibility to nine commonly used antifungal agents. The optimal growth parameters for this strain were determined to be a temperature of 30 °C and a pH of 5.0. In solid-state fermentation using cotton meal at 30 °C with initial fermentation conditions (10% corn flour added as an external carbon source, 40% moisture content, and 6% inoculum concentration) for 3 days, strain ZYS-3 achieved a gossypol removal rate of 73.57%. Subsequent optimization of the fermentation process, including the addition of 10% corn flour as an external carbon source, adjustment of moisture content to 55%, and inoculum concentration to 10%, resulted in an increased gossypol removal rate of 89.77% after 3 days of fermentation, representing a 16.2% enhancement over the initial conditions. Assessment of gossypol removal activity revealed that strain ZYS-3 predominantly removes gossypol through the secretion of extracellular enzymes targeting specific active groups (phenolic hydroxyl groups and aldehyde groups) within the gossypol molecule. These enzymes facilitate oxidation and elimination reactions, leading to the opening of the naphthalene ring and subsequent removal of gossypol. Full article

Beta-glucans (β-glucans), polysaccharides found in cereals and fungi, are recognized for their prebiotic and potential anti-cancer activities, particularly in the colorectal area. This study aims to optimize the production of β-glucan through the solid-state fermentation of germinated Riceberry rice with Pleurotus ostreatus and evaluate the bioactivities of the resulting extract. The crude β-glucan extract, obtained with a recovery rate of 54.95% and 79.98% purity, demonstrated an effective extraction process, as confirmed by thermogravimetric analysis (TGA). Fourier-transform infrared spectroscopy (FTIR) analysis verified the presence of β-1,3/1,6-glycosidic linkages, characteristic of the bioactive β-glucans found in yeast and mushrooms. The biological assessment demonstrated the extract’s functional properties. At a concentration of 1 mg/mL, the crude β-glucan extract significantly promoted the growth of probiotics Lacticaseibacillus rhamnosus and Bacillus coagulans, exhibiting high Prebiotic Index (PI) values of 6.36 ± 0.72 and 115.70 ± 10.19, respectively, with PI values indicating strong prebiotic potential. For comparison, the standard prebiotic inulin yielded PI values of 0.41 ± 0.09 and 90.53 ± 2.28 for the same respective bacteria, highlighting the superior performance of the fungal-fermented β-glucan. Furthermore, the extract displayed efficacy in inhibiting colon cancer cells in preliminary in vitro tests. It reduced the viability of the SW480 colorectal cancer cell line by 66.23% and induced cell death in 27.94 ± 0.93% of the cells after 48 h of treatment, performing comparably to a commercial yeast β-glucan standard. Crucially, the extract showed no significant cytotoxicity toward the normal human colon cell line, CCD-841 CoN. These findings highlight the promising method of fungal solid-state fermentation on germinated Riceberry rice in the production of high-purity, bioactive β-glucans for use in functional foods. Full article

Sauce-flavor Daqu is the solid-state fermentation starter for sauce-flavor Baijiu. Its microbial community influences flavor formation, yet links between community change, process conditions, and flavor development during high-temperature fermentation remain unclear. We investigated Daqu fermentation by integrating high-throughput sequencing, monitoring of physicochemical parameters, and analysis of volatile compounds. Fermentation temperature showed three phases: rapid rise, fluctuating plateau, and gradual decline. High temperatures were associated with increased thermophilic microbes such as Bacillus and Thermoascus and with higher levels of reducing sugars and amino acid nitrogen; amylase, protease, and other hydrolase activities were detected. Bacterial composition varied more than fungal composition; Firmicutes and Ascomycota were the dominant phyla, and Bacillus and Thermoascus were abundant genera. Canonical correspondence analysis associated reducing sugars, acidity, and moisture with early community shifts, and amino acid nitrogen with later shifts; reducing sugars and moisture showed the strongest associations. Filamentous fungi and Bacillus correlated with pyrazine-type compounds. These results link microbial composition, process parameters, and flavor profiles, and may inform the standardization and mechanization of Daqu production. Full article

Due to its high content of lignocellulose, cotton stalk is difficult to degrade naturally and utilize effectively, so it is often regarded as waste. In this study, the effects of Pleurotus ostreatus XH005, Lactiplantibacillus plantarum LP-2, and cellulase enzyme on the cotton stalk substrate under aerobic solid-state fermentation (SSF) conditions were investigated, and the metabolites were analyzed to identify potential functional compounds in the cotton-stalk-fermented feed. Preliminary optimization results obtained through single-factor experiments were as follows: fermentation time 14 days, XH005 inoculum size 8.00% (v/m), material-to-water ratio 1:0.50 (v/m), LP-2 inoculum size 2.00% (v/m), and cellulase addition 0.60% (m/m). Based on these single-factor experimental results, XH005 inoculum size, LP-2 inoculum size, material-to-water ratio, and cellulase addition were selected as independent variables. Through response surface methodology (RSM) optimization experiments, 29 experimental groups were designed. Subsequently, based on Box–Behnken analysis of variance (ANOVA) of lignin and cellulose content, along with contour and response surface plots, the optimal aerobic solid-state fermentation parameters were determined as follows: fermentation time 14 days, XH005 inoculum: 7.00% (v/m), material-to-water ratio: 1:0.55 (v/m), LP-2 inoculum: 2.00% (v/m), and cellulase enzyme addition: 0.65% (m/m). Results showed that compared with the control group (CK), the optimized group exhibited a 27.65% increase in lignin degradation rate and a 47.14% increase in cellulose degradation rate. Crude protein (CP) content increased significantly, while crude fiber (CF), detergent fiber and mycotoxin contents decreased significantly. Non-targeted metabolic analysis indicated that adding cellulase and inoculating Pleurotus ostreatus XH005 and Lactiplantibacillus plantarum LP-2 in aerobic SSF of cotton straw feed produced functionally active substances such as kaempferol (C343), carvone (C709) and trilobatin (C604). Therefore, this study demonstrates that microbial-enzyme co-action SSF significantly enhances the nutritional composition of cotton stalk hydrolysate. Furthermore, this hydrolysate is suitable for the production of functional compounds, endowing the fermented feed with health-promoting properties and enhancing the utilization of cotton processing byproducts in the feed industry. Full article

Pectins are high-value plant cell-wall polysaccharides with extensive applications in the food, pharmaceutical, textile, paper, and environmental sectors. Traditional extraction and processing methodologies rely heavily on harsh acids, high temperatures, and non-renewable solvents, generating substantial environmental and economic costs. This review consolidates recent advances across the entire Bacillus–pectinase value chain, from green pectin extraction and upstream substrate characterization, through process and statistical optimization of enzyme production, to industrial biocatalysis applications. We propose a practical roadmap for developing high-efficiency, low-environmental-footprint enzyme systems that support circular bioeconomy objectives. Critical evaluation of optimization strategies, including submerged versus solid-state fermentation, response surface methodology, artificial neural networks, and design of experiments, is supported by comparative data on strain performance, fermentation parameters, and industrial titers. Sector-specific case studies demonstrate the efficacy of Bacillus pectinases in fruit-juice clarification, textile bio-scouring, paper bio-bleaching, bio-based detergents, coffee and tea processing, oil extraction, animal feed enhancement, wastewater treatment, and plant-virus purification. Remaining challenges, including enzyme stability in complex matrices, techno-economic scale-up, and structure-guided protein engineering, are identified. Future directions are charted toward CRISPR-driven enzyme design and fully integrated circular-economy bioprocessing platforms. Full article