Search Results (766)

To investigate how steam-explosion pretreatment affects humification during sawdust composting, an aerobic composting experiment was conducted using sawdust, chicken manure, and spent mushroom substrate as feedstocks. Two treatments were established—a steam-explosion-pretreated sawdust group (SEW) and an untreated sawdust control (CK)—each with three replicate reactors. Samples were collected dynamically at five key composting stages (initial, heating, thermophilic, cooling, and maturation) for physicochemical, enzymatic, and microbial community analyses. Linear mixed-effects model analysis revealed that enzyme activities were significantly affected by treatment, composting time, and their interaction. SEW significantly enhanced cellulase and polyphenol oxidase activities, and increased laccase and peroxidase activities at specific stages. Compared with CK (humic substances, 75.30 g/kg), SEW promoted higher humic substance accumulation (120.80 g/kg) and altered the dynamics of dissolved organic carbon. Microbial co-occurrence networks in SEW (50 nodes, 602 edges) were more complex than CK (49 nodes, 464 edges), indicating tighter microbial interactions. Path analysis revealed that HS in CK was mainly influenced by DOC and temperature, while HS in SEW was associated with enzyme activities, microbial diversity, and Pseudogracilibacillus. These results suggest that steam-explosion pretreatment enhances substrate transformation and humic substance formation during composting. Full article

Subterranean termites, particularly Odontotermes obesus, cause severe damage to forest nurseries and plantations in arid and semi-arid ecosystems. This study demonstrates the dual functional role of endophytic entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana, in termite suppression and induction of plant defense responses. Laboratory bioassays revealed significantly higher virulence of M. anisopliae, with a lower LT₅₀ (lethal time required to cause 50% mortality) of 33.1 h compared to B. bassiana (46.7 h), a steeper probit slope (5.4 ± 0.3), and strong model fit (R² = 0.95), indicating rapid and synchronized mortality. Endophytic colonization varied across host species and application methods, with soil incorporation consistently outperforming foliar inoculation. Maximum colonization (82.5%) was recorded in Tecomella undulata and exceeded 80% in Azadirachta indica under M. anisopliae. Biochemical analyses revealed significant increases in protein (up to 3.5 mg g⁻¹), phenols (3.7 mg g⁻¹), and tannins (2.7 mg g⁻¹). Activity of defense enzymes was significantly enhanced, with catalase reaching 263.5 U mL⁻¹, while Phenylalanine ammonia-lyase and Tyrosine ammonia-lyase exceeded 170 and 198 U mL⁻¹, respectively, indicating activation of antioxidant and phenylpropanoid pathways. Molecular docking analysis further revealed strong interactions between fungal metabolites and termite cellulase, with Bassianin (−8.4 kcal mol⁻¹) and Tenellin (−8.1 kcal mol⁻¹) showing the highest binding affinities. These findings highlight the combined biochemical and molecular mechanisms underlying fungal-mediated termite suppression and plant defense induction, and future research should prioritize transcriptomic validation, rhizosphere microbiome interactions, formulation optimization, and long-term multi-location field evaluation to support sustainable termite management strategies. Full article

The potential of Trichoderma nordicum (Hypocreales, Ascomycota), a recently described species, for antagonism and use in the biocontrol of oomycete-caused plant diseases is unknown. Trichoderma is a well-known genus for containing microbial antagonists and biocontrol agents. The T. nordicum in this study was isolated from decomposing wood, and rpb2 and tef1 barcode sequencing demonstrated that the isolates were a match to the reference T. nordicum and T. nigricans strains. Since T. nordicum was described before T. nigricans, the isolates were assigned to T. nordicum, although taxonomic uncertainty between these species requires future clarification. In dual-culture confrontation assays, T. nordicum overgrew five economically important oomycete plant pathogens (Phytophthora capsici, P. sojae, Pythium aphanidermatum, P. myriotylum, and Globisporangium ultimum). The inability to recover viable P. aphanidermatum and P. capsici from the parts of the plate overgrown by T. nordicum, coupled with protease and endo-cellulase activities, correlates with T. nordicum having antagonistic abilities. Inoculation with T. nordicum preventively reduced the levels of cucumber seedling damping-off caused by P. aphanidermatum by up to 70%. The T. nordicum biocontrol effects against pepper blight caused by P. capsici were greater than 80%, compared to an autoclaved T. nordicum spore control. T. nordicum could also significantly promote the growth of pepper, with plant weight increased by up to 40%, compared to an autoclaved-spore control. In contrast, T. nordicum could not be used to control Pythium soft rot of ginger caused by P. myriotylum, even though P. myriotylum was overgrown by T. nordicum, suggesting host- or pathosystem-specific factors influence biocontrol efficacy. In summary, T. nordicum is a promising biocontrol agent for use in the control of pepper blight caused by P. capsici, and also has potential for use in the control of other oomycete-caused plant diseases in vegetable production systems. Full article

Municipal wastewater represents an underutilized secondary biomass resource rich in organic carbon and nutrients that can be valorized through biotechnological conversion. In this study, we developed an integrated multi-microbial biorefinery platform to transform municipal wastewater into value-added biofuel via sequential bacterial treatment, microalgal biomass generation, and fungal-assisted harvesting. Wastewater was first pretreated with Bacillus subtilis to enzymatically hydrolyze complex organic substrates and enrich the medium with bioactive metabolites, including auxins and gibberellins. The conditioned wastewater was subsequently used to cultivate Chlorella vulgaris, followed by biomass recovery using Trichoderma viride pellets as a sustainable bioflocculant. The integrated consortium significantly enhanced nutrient removal efficiency and promoted algal biomass accumulation, lipid enrichment, and biodiesel productivity compared to monoculture controls. Elevated hydrolytic enzyme activities (cellulase, protease, and amylases) facilitated organic matter conversion into bioavailable substrates, while increased phytohormone levels stimulated algal growth and lipid biosynthesis. Additionally, fungal bioflocculation substantially improved biomass recovery efficiency, reducing the need for energy-intensive harvesting technologies. This work highlights the potential of a biotechnology-driven approach for integrating wastewater remediation with biofuel production. By integrating microbial metabolism, enzymatic transformation, and sustainable separation processes, the proposed biorefinery system suggests a potentially low-carbon approach for simultaneous environmental remediation and biomass valorization, although further life cycle and energy balance analyses are required to validate this aspect. Full article

To investigate the key role of endophytic fungi in maintaining host adaptability and overall health, endophytic fungi were isolated from healthy root, stem and leaf tissues of Impatiens hawkeri, and the dominant strain FG8 with growth-promoting and antagonistic functions was screened. Strain FG8 was identified as Thelonectria veuillotiana by morphological and molecular biological methods. It exhibited an antifungal rate of 58.57% against Stagonosporopsis cucurbitacearum, the pathogen causing leaf spot disease of I. hawkeri. The broad-spectrum antifungal activity was verified by the plate confrontation method, and FG8 showed inhibitory effects on six common pathogenic fungi, with the highest inhibition rate of 64.5% against Apiospora intestini. Furthermore, strain FG8 displayed remarkable growth-promoting and antagonistic characteristics: it produced indole-3-acetic acid at 12.74 μg/mL, and possessed the abilities of phosphate solubilization, potassium mobilization, nitrogen fixation and siderophore synthesis. Its antagonistic activity was mediated by β-glucanase, amylase, cellulase and pectinase. Meanwhile, FG8 significantly induced the activities of four defensive enzymes in I. hawkeri, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and polyphenol oxidase (PPO). Seed growth-promotion experiments demonstrated that the root length, plant height, fresh weight and dry weight of seedlings in the FG8-treated group were significantly higher than those in the control group. These results indicate that strain FG8 has both growth-promoting and biological control functions, which can provide a potential resource for the biological control of I. hawkeri leaf spot and the development of fungal fertilizers. Its field application effect and mechanism of action need to be further explored. Full article

Brewer’s spent grain (BSG) is an abundant lignocellulosic by-product whose valorization can support circular bioeconomy strategies. This study evaluated BSG bioconversion by Aspergillus oryzae ATCC 10124 under solid-state fermentation (SSF) to produce lignocellulolytic enzymes and release second-generation (2G) sugars relevant to biorefinery applications. SSF was monitored over 0–10 days, and FPase, endo-cellulase, β-glucosidase, xylanase, mannanase, amylase, and ligninolytic enzyme activities were quantified. Enzymatic crude extracts were further assessed in SDS-PAGE analysis. Glucose, cellobiose, xylose and arabinose release and consumption were tracked throughout fermentation, and substrate transformation was supported by FTIR. The secretome exhibited a predominantly hydrolytic profile, with maximal hemicellulolytic and cellulolytic activity around days 2–4, as well as sustained amylase activity. Ligninolytic activity was not detected. Sugar profiles indicated rapid early hydrolysis of glucose, followed by progressive pentose release. The stabilization and decline were consistent with fungal uptake. Changes in the carbohydrate fingerprint and SDS–PAGE banding supported structural polysaccharide remodeling and hydrolytic protein secretion. Thus, this SSF platform confirmed certain potential for low-cost cellulolytic and hemicellulolytic enzyme generation. However, because sugar accumulation was temporary and followed by consumption, this system is best interpreted as a biological pretreatment and enzyme-generation step that supports subsequent downstream valorization. Full article

Saponins, the primary bioactive constituents with immunomodulatory activities in Baoyuan decoction—a traditional Chinese medicine formula composed of ginseng, astragalus, licorice, and cinnamon—are limited by low extraction yield, poor stability, and easy degradation. In this study, cellulase and pectinase were used for the extraction of saponins from Baoyuan decoction and optimized by response surface methodology. Subsequently, the optimal extracts were microencapsulated by spray drying with soy protein isolate (SPI) or high-oleic acid soy protein isolate (HOSPI) and pectin (PE) as composite wall materials, followed by application evaluation in gummies and in vitro digestion. After optimization, the total saponin yield was 63.68 ± 0.15 mg/g. HOSPI-PE microcapsules (HBP) had a higher encapsulation efficiency (90.38%), smaller particle size, and lower hygroscopicity than SPI-PE ones (SBP). Furthermore, both microcapsules showed good stability during storage and controlled release, with 60.9% of saponins in SBP and 65.8% in HBP being delivered to the intestinal phase during in vitro digestion of microparticles. When applied in gummies, microcapsule gummies retained satisfactory sustained-release in vitro digestion (23.0% released in the stomach and 66.2% in the small intestine). In contrast, the unencapsulated gummies exhibited a burst release (74.4%) at 30 min in gastric digestion. This study provides theoretical and technical insights into the development of plant-derived functional foods and promotes the practical application of microencapsulation in functional gummy candies. Full article

Cold-active cellulases are highly desirable for temperature-sensitive biomass valorization and food processing, yet they remain scarce in conventional industrial fungal platforms. In this study, a novel cold-induced cellobiohydrolase, VvCBHI-II, was mined from the mushroom Volvariella volvacea and successfully engineered into the industrial workhorse Trichoderma reesei via site-specific homologous replacement. Structural homology modeling revealed that the substitution of the flexible B3 loop with a β-sheet creates a more open substrate-binding cleft in VvCBHI-II. Consequently, the purified VvCBHI-II exhibited robust endoglucanase-like characteristics with superior catalytic efficiency on amorphous cellulose. At 10 °C, the engineered cellulase complex demonstrated an 8.1-fold increase in filter paper activity compared to the wild-type strain. Mechanistic structural analyses indicated that the open cleft architecture elongates and weakens the hydrogen-bonding network with the cellobiose product, facilitating rapid product dissociation and alleviating severe cold-induced product inhibition. In practical applications, the engineered cold-active enzyme complex exhibited an exceptional saccharification capacity on natural pear pomace at 10 °C. Furthermore, when applied to simulated fruit juice processing, it significantly maximized the extraction yield, elevated the sweetness response, and substantially mitigated undesirable bitterness and astringency. This study elucidates the structural-functional paradigm of cold-adapted cellobiohydrolases and provides a promising strategy for formulating highly efficient, energy-saving biocatalysts for the food and biorefinery industries. Full article

In the post-antibiotic era, the Bacillus-based direct-fed beneficial microorganisms are emerging as a cornerstone for sustainable animal farming. This study aimed to screen and evaluate Bacillus strains with probiotic potential for use as feed additives. A total of 394 Bacillus strains were initially screened based on their extracellular enzyme production (cellulase, protease, and amylase) and antibacterial activities against Escherichia coli, Staphylococcus aureus, and Salmonella enterica. Two strains, Bacillus velezensis FJAT-10508 and FJAT-13563, were selected and subsequently subjected to in vitro probiotic characterization, safety assessment, and whole-genome analysis. The results demonstrated that both strains exhibited α-hemolysis, acceptable antibiotic susceptibility profiles, absence of invasion and cytotoxicity effect on the Caco-2 cells, and no mobile virulence or antibiotic resistance genes, indicating their safety as probiotic candidates. High endospore-forming efficiencies (72.4–90.8%), strong auto-aggregation (74–85%) and co-aggregation abilities (52–82%) were observed. In addition, both strains showed considerable tolerance to simulated gastrointestinal conditions, with vegetative cell and endospore survival rates of 28.33–38.33% and 85–89.67% at pH 2.0, and 38.33–43.33% and 90.33–96.33% in 0.3% bile salts, respectively. Overall, B. velezensis FJAT-10508 and FJAT-13563 demonstrated robust in vitro probiotic properties, supporting their potential application as reliable Bacillus-based feed additives. Full article

To develop safe and effective preservatives for fresh-cut produce, this study elucidates the multi-pathway mechanisms through which Melatonin (MT) regulates postharvest senescence in fresh-cut potatoes. Treatment with 0.1 mmol/L exogenous MT effectively inhibited browning and softening during storage. In terms of browning control, MT suppressed PPO and POD activities by 46% and ~10% at the end of storage (day 12), while enhancing enzymatic and non-enzymatic antioxidant capacity by 1.1- to 1.6-fold on average throughout storage. This alleviated oxidative damage and membrane lipid peroxidation, thereby reducing tissue browning. Regarding texture maintenance, MT downregulated PME and cellulase activities by 23% and 19% at the end of storage, activated phenylpropanoid metabolism, and inhibited starch degradation (maintaining 19% higher starch content), thus preserving cell wall structure and firmness (9.2% higher at the end of storage). Further analysis revealed that MT antagonized ethylene biosynthesis, upregulated StMYB168 expression (5.8-fold higher than control on average), and activated endogenous MT biosynthesis, establishing a self-sustaining positive regulatory cycle. Correlation analysis confirmed close relationships among physiological processes, signaling responses, and quality traits, with significant associations between firmness and starch content (r = 0.72), color indices and PPO/POD (|r| > 0.65), and MT biosynthesis genes and metabolic pathways (r = 0.65–0.75) (p < 0.01). Full article

Medlar (Mespilus germanica L.) is a plant species that belongs to the Rosaceae family. Despite the nutritional and functional value of the medlar fruit, there is limited research, particularly regarding its potential as a source of dietary fibers, indigestible plant-based components, important for improving health. Fungal cellulase enzymes were used to treat medlar fruit in physiological (PRM) and consumable (CRM) maturity and obtain insoluble dietary fibers (IDF). The yield of obtained insoluble dietary fibers was 83% for both PRM and CRM. Fungal strains Aspergillus welwitschiae have proven to be significant producers of the cellulase enzyme complex and are also safe for use in food production. Swelling capacity exhibited the most pronounced response to the enzymatic treatment; 8.51–8.65% vs. 12.24–12.86% (untreated and treated fruits, respectively). Dietary fibers extracted from medlar fruits exhibited antioxidant activity that can be attributed to the presence of bound polyphenolic compounds within the fiber material. Microscopic analysis and FTIR spectra revealed structural changes in the medlar fibers due to enzyme activity, indicating partial hydrolysis of lignocellulosic components. This process enhances the functional properties of medlar-based IDF, making it a valuable ingredient for fiber-enriched food products. Full article

Actinidia arguta fruits are highly perishable due to their thin, glabrous skin and high respiration rate. The primary objective of this study was to investigate the effects of a coating composed of 1.2% cinnamon essential oil (CEO) combined with 1% chitosan (CH) on the storage quality, cell wall structure, and cell wall metabolism in A. arguta fruits after subjecting them to 25 ± 1 and 4 °C. Results showed that this coating composition effectively maintained fruits’ postharvest appearance and firmness, reduced the rate of weight loss, and preserved the fruit’s original sensory flavor. Furthermore, the coating treatment significantly delayed the conversion of protopectin to soluble pectin, the increase in cellulose content, and the decrease in acid-insoluble solid (AIS) content. Furthermore, low activities of polygalacturonase (PG), pectin methylesterase (PME), pectin lyase (PL), cellulase (Cx), β-glucosidase (β-Glu), and β-galacturonidase (β-Gal) were found in the treatment during storage. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observed that the composite coating treatment strongly maintained the integrity of fruit cell wall structure and exhibited positive effects under room temperature conditions, with its protective effects further enhanced and prolonged under refrigerated conditions. In conclusion, this combination treatment extended the postharvest storage life of A. arguta, possibly by inhibiting cell wall degradation, maintaining fruit firmness, and regulating the activity of cell wall metabolism. Full article

Flammulina filiformis is a significant edible and medicinal fungus; however, its industrial expansion has been limited by traditional cultivation practices, highlighting an urgent need for resource-efficient and environmentally friendly alternative substrates. This study investigated the partial replacement of traditional substrates with Cenchrus fungigraminus. Utilizing the simplex-lattice method for optimization, we identified an optimal cultivation formulation, composed primarily of 20% C. fungigraminus and 28% corncobs. This formulation achieved a biological efficiency of 131.92% and enhanced the nutritional content of the fruiting bodies. Monitoring dynamic enzyme activity revealed that the yield was positively correlated with post-primordium cellulase activity, whereas mycelial growth was negatively correlated with cellulase activity during the vegetative stage. Transcriptomic analysis further indicated that key genes involved in carbohydrate metabolism and cellular processes were significantly upregulated in the optimized formulation. These results suggest that the addition of C. fungigraminus enhances nutrient conversion efficiency by regulating the expression of genes associated with carbon and nitrogen metabolism, ultimately leading to an approximately 15% increase in the biological efficiency of fruiting bodies, and a profit increase of 379.37 Chinese Yuan (CNY) per ton of cultivation substrate, demonstrating substantial economic benefits. In summary, this study provides a theoretical and technical foundation for cultivating F. filiformis using C. fungigraminus, contributing to the advancement of the industry toward resource conservation and environmental sustainability. Full article

Secondary salinization in mulched drip-irrigated cotton fields of arid oasis–desert transition zones in Xinjiang imposes coupled root-zone constraints, including salt-induced aggregate structural degradation and ionic stress. However, field evidence remains limited on whether integrating a structure-oriented soil conditioner with humic acid can generate stable improvements across growing seasons. A two-year field experiment with a randomized block design (three replicates) was conducted to evaluate four treatments: control (CK), polyacrylamide (PAM, 30 kg ha⁻¹), humic acid (HA, 450 kg ha⁻¹), and PAM + HA. Soil physical and chemical properties and aggregate-size distribution were determined after harvest, while enzyme activities and root traits were assessed at the flowering–boll stage. Structural equation modeling (SEM) and random forest (RF) analysis were used to explore soil–root–yield linkages and identify key soil predictors associated with yield variation. Treatment effects were most evident in the 0–20 cm layer, with PAM + HA showing the greatest overall improvement. In the topsoil, PAM + HA lowered soil pH from 8.35 to 7.88 in 2024 (p < 0.05), increased soil organic carbon (SOC) to 4.29 g kg⁻¹ in 2025 (p < 0.01), and increased NO₃⁻–N to 25.51 and 30.27 mg kg⁻¹ in 2024 and 2025, respectively (both p < 0.05). PAM + HA also enhanced cellulase activity from 6.17 to 16.85 mg glucose g⁻¹ 72 h⁻¹ in 2024 and increased seed cotton yield to 6683.69 and 5996.89 kg ha⁻¹ in 2024 and 2025, with a 51.0% yield increase over CK in 2024. SEM showed that root development had the strongest direct positive effect on yield (β = 0.79, R² = 0.63; goodness of fit (GOF) = 0.74), while random forest identified alkaline phosphatase, cellulase, and NO₃⁻–N as the main yield predictors (out-of-bag R² (OOB R²) = 0.672, p = 0.01). This study elucidated the effects of the combined application of a structure-oriented soil conditioner and humic acid on the root-zone environment of mulched drip-irrigated cotton fields in arid regions, providing a theoretical basis for the coordinated regulation of soil structural improvement and nutrient activation in saline–sodic cotton fields. Full article

Saliva is an important biological matrix that allows the investigation of various welfare parameters; in ruminants, it is abundant and can be easily collected without requiring professional veterinary intervention. The aim of the investigation was to provide additional information on both digestive and antioxidant enzymes of sheep farmed in good welfare conditions, assessed with the Animal welfare indicators (AWIN) protocol. Small surgical forceps holding a Salivette^® device (Sarstedt, Nümbrecht, Germany) were gently inserted into the sheep’s mouths without any force. The sheep chewed the swabs independently for a few seconds, allowing saliva collection. Seventeen enzymes from the saliva of 15 sheep were analyzed: antioxidant enzymes (catalase, glutathione S transferase), proteolytic enzymes (trypsin, chymotrypsin, N-aminopeptidases, carboxypeptidase A and B), carbohydrases (glucose oxidase, amylase, cellulase, lignin peroxidase, chitinase and α-glycosidase), and esterases (alkaline and acidic phosphatases, lipase and esterase). Esterase activity showed the highest value (12.95 ± 1.25 U/mg of proteins), whereas lignin peroxidase activity showed the lowest (2.23 ± 0.37 µU/mg of proteins). The activity of all enzymes was observed except for glutathione S transferase and α-glycosidase. Among the enzymes, lipase activity has already been identified as a biomarker of stress in sheep saliva. This investigation may represent a basis for further investigations into the diet and adaptive responses of sheep to different environmental conditions. Furthermore, samples collected using the Salivette^® device can be easily obtained without requiring specialized staff and without causing any stress to the animals. Further investigations into the origin of individual enzymes using a proteomic approach are desirable. Full article