Search Results (1,077)

Although microbial remediation is a promising strategy for PAH pollution control, its field application remains a significant challenge. PAH-degrading microbial consortia were enriched from contaminated sites in Nanjing. High-throughput sequencing was applied to analyze the community structure and functional characteristics of bacteria and fungi, and the phenanthrene degradation performance of free consortia and sodium alginate-activated carbon-immobilized composite beads was systematically evaluated. Results showed that the distance from the pollution source was the key factor driving the differentiation of microbial community structure. For bacteria, sites closer to the pollution source showed significantly lower bacterial diversity and richness, while an opposite trend was observed for fungi. Proteobacteria (40–87%) and Ascomycota (51–88%) were the dominant phyla of bacterial and fungal communities, respectively. Despite significant differences in genus-level community composition among samples, the functional gene abundance related to PAHs metabolism was highly similar across all consortia. The immobilized composite beads achieved a significantly higher phenanthrene degradation efficiency (94.70–99.26%) compared with free consortia (65.84–85.78%). The embedding material had a significant effect on degradation performance, while nutrient sources showed no significant impact on the degradation efficiency. This study provides theoretical support for the application of immobilized microbial technology in PAH-contaminated site remediation. Full article

The intercropping system is used for weed control in orchards, but the intercrops need to be well-designed to fit into the row spaces of fruit trees. In this study, the citrus (Citrus reticulata cv. Chachiensis) row spaces were intercropped with either soybean (Glycine max (L.) Merr.) or sweet potato (Ipomoea batatas (L.) Lam.), and their effects on weed control, soil physiochemical properties, and soil microbiome were compared to the natural weeds. Both plant species were effective in reducing the orchard weeds, and their different varieties commonly improved soil organic matter, available P and K, and beneficial metal elements compared to the weeds. Even though the soil fungal and bacterial richness and diversity of the intercrops were not significantly altered, their composition, structure, and function were distinctive to those of the weeds. The soils of the intercrops generally enriched with the fungal genera of Talaromyces and Penicillium and the bacterial genera Sphingomonas, Knoellia, and Nocardioides. Accordingly, the altered microbial communities, in taxonomy, correlated to the enriched cellular functional pathways of glycolysis and gluconeogenesis, homologous recombination, nitrogen metabolism, lipoic acid metabolism, mismatch repair, DNA replication, nicotinate and nicotinamide metabolism. Taken together, these results imply that intercrops and weeds exert distinct effects on soil nutrient accumulation, and these effects are associated with their differential impacts on soil microbiomes—which are likely driven by the rhizosphere activities of the intercrops. Full article

Alternaria brassicicola is a necrotrophic fungal pathogen causing black spot disease on cruciferous crops worldwide. In this study, we comprehensively characterized the pathogenic isolate Ab0920a from diseased broccoli in Shanghai using morphological, phylogenetic, host range, fungicide sensitivity, genomic, and functional analyses. Pathogenicity tests on 27 cruciferous varieties revealed a broad host range with varying resistance levels. Fungicide sensitivity assays showed that fluxapyroxad (EC₅₀ = 0.0695 µg/mL), prochloraz (0.0711 µg/mL), and difenoconazole (0.0863 µg/mL) were highly effective, whereas fluazinam was least effective. Genome-wide annotation identified 941 secreted proteins (8.95% of the proteome) and 237 candidate effectors, including 31 small cysteine-rich secreted proteins and 68 homologs of known virulence factors. Conserved effector-associated motifs (e.g., RXLR, [Y/F/W]xC) were detected, and carbohydrate-active enzyme CAZyme annotation revealed diverse families potentially involved in plant cell wall degradation. Functional validation using the pSUC2 yeast system confirmed that N-terminal signal peptides of tested effectors are competent for secretion. A PVX-based transient expression assay in Nicotiana benthamiana identified two effectors that suppress Bax-induced programmed cell death, suggesting their potential roles in modulating host immunity. Overall, this study provides comprehensive insights into the pathogen Ab0920a, offering resources for disease management and functional studies on necrotrophic fungal pathogenesis. Full article

Background/Objectives: Mushroom-derived phenolic compounds are gaining attention as bioactive molecules with potential roles in gut microbiota modulation, intestinal health, and metabolic regulation. Although mushroom polysaccharides are well established as fermentable substrates, the contribution of fungal phenolics to microbiota–host interactions remains less defined. This review aimed to critically analyse the evidence supporting mushroom-derived phenolic compounds as emerging prebiotic-like modulators of gut microbiota, intestinal function, and host metabolism. Methods: A narrative critical review was conducted using scientific literature retrieved from PubMed, Scopus, Web of Science, and Google Scholar. Studies addressing phenolic profiling in edible and medicinal mushrooms, gastrointestinal digestion, colonic fermentation, microbial biotransformation, gut microbiota modulation, intestinal barrier function, inflammation, and metabolic outcomes were considered. Particular attention was given to chromatographic and mass spectrometry-based studies, in vitro digestion/fermentation models, mechanistic studies, animal experiments, clinical trials, systematic reviews, and meta-analyses. Results: Current evidence shows that mushrooms contain diverse phenolic compounds, mainly phenolic acids such as gallic, protocatechuic, caffeic, p-coumaric, ferulic, vanillic, syringic, and cinnamic acids. Due to limited small intestine absorption, a substantial fraction of these compounds may reach the colon, where they undergo microbial biotransformation into smaller phenolic metabolites. These metabolites may influence microbial ecology, support beneficial taxa, modulate short-chain fatty acid production indirectly, attenuate oxidative stress and inflammatory signaling, and contribute to intestinal barrier integrity. However, most evidence derives from in vitro and preclinical studies, while human data remain limited and are mainly based on whole-mushroom interventions. Conclusions: Mushroom-derived phenolic compounds are promising prebiotic-like modulators within the microbiota–metabolite–host axis. Nevertheless, their specific contribution cannot yet be quantitatively distinguished from that of other mushroom constituents, particularly β-glucans, chitin, and other fungal polysaccharides, because most available evidence derives from whole-mushroom matrices, crude extracts, or polysaccharide-rich preparations rather than isolated phenolic fractions. Future studies should compare whole mushroom preparations, polysaccharide-rich fractions, and standardized phenolic-rich extracts, integrating metabolomics, microbiome profiling, and well-designed clinical trials to clarify the relative mechanistic and therapeutic relevance of mushroom phenolics. Future studies should use standardized phenolic-rich extracts, metabolomics, microbiome analysis, and well-designed clinical trials to clarify their mechanistic relevance, clinical significance, and translational potential. Full article

Social insect pests such as leaf-cutting ants challenge conventional pest management because effective control must disrupt colony-level organization rather than target individual insects. Colony persistence depends on the mutualistic association between gardener workers and their cultivated fungus, Leucoagaricus gongylophorus. Compounds that selectively impair these components while preserving forager-mediated bait transport may therefore offer strategic advantages. We evaluated the essential oils of weeping willow (Salix babylonica), Surinam cherry (Eugenia uniflora), weeping bottlebrush (Melaleuca viminalis), ginger (Zingiber officinale), and black pepper (Piper nigrum) against two leaf-cutting ant species, Atta sexdens and Acromyrmex subterraneus, after characterizing their chemical composition by GC–MS. The oils displayed distinct terpenoid profiles: bottlebrush oil, for instance, was dominated by 1,8-cineole and α-pinene, while ginger oil was rich in camphene and β-phellandrene. Forager and gardener workers were tested separately, along with their symbiotic fungus. Responses were generally concentration-dependent, although effects varied among oils and biological targets. Ginger oil exhibited strong fungicidal activity, but only at the highest concentration tested (100 mg mL⁻¹). Bottlebrush oil showed marked toxicity to A. sexdens gardeners at concentrations as low as 0.10 mg mL⁻¹, while effects on foragers were comparatively low. The remaining oils produced limited or inconsistent responses. These findings indicate that caste-selective toxicity and fungal suppression are achievable but not widespread among essential oils. Bottlebrush oil emerges as a promising candidate for further investigation, particularly regarding its constituent compounds and potential synergistic interactions for toxic bait development. Full article

This study investigates the breeding of the German wine yeast Oppenheimer Kreuz 1894, which carries a FOT1 allele of a fungal oligopeptide transporter, with Freya, a Kveik ale yeast, to enhance fermentation performance and aroma in beer and wine. By combining Kveik traits (osmotolerance, thermotolerance, and rapid fermentation kinetics) with those of a German wine yeast (ethanol tolerance, broadened nitrogen utilization, and aroma production) and introducing FOT1 into an ale background via classical breeding, we aimed to leverage the Saccharomyces biodiversity to improve fermentation activity and expand aromatic complexity. Fermentation products and volatile aroma compounds were quantified by HPLC and HS-SPME-GC-MS. Spore clone derivatives of initial hybrid strains (F₂-generation) showed improved fermentation profiles with increased CO₂ production. In wine fermentations, the best-performing spore clone, GYBC 901, yielded a rich aromatic profile with elevated fruity and floral notes. In beer fermentations, GYBC 899 produced the most diverse and complex aroma. FOT1 was of minor relevance to the breeding outcome, whereas meiotic recombination generated a set of diverse spore clones. These results highlight the potential of strategic yeast breeding to optimize fermentation processes and tailor flavor profiles to diverse product targets. Future work will elucidate metabolic pathways underlying these phenotypes and advance the development of application-specific strains, offering avenues to enhance beverage quality and product differentiation in the fermentation industry. Full article

The floodplains of the Paraná and Paraguay rivers form the Chaco wetland, one of the most species-rich plant ecosystems in Argentina. Because wild grasses can serve as reservoirs of fungal species that cause disease and mycotoxin contamination of cereal crops, we examined asymptomatic, wild grasses from the Chaco wetlands for the presence of the genus Fusarium, which includes multiple species that cause agriculturally important diseases and/or mycotoxin contamination of crops. We focused our efforts on the identification and characterization of the multispecies lineage known as the Fusarium fujikuroi species complex (FFSC). Using morphological traits and partial DNA sequences of the TEF1 gene, we determined that 58 isolates recovered from the grasses were members of FFSC. Fifty of the isolates were identified as one of six FFSC species, including the economically important plant pathogenic species F. proliferatum, F. subglutinans, and F. verticillioides. To our knowledge, two of the species, F. anthophilum and F. pseudocircinatum, have not been reported previously in Argentina. Our analyses also indicated that eight of the FFSC isolates were a novel species, herein described as Fusarium varsavskyanum. A polymerase chain reaction (PCR) assay and genome sequence data indicate that each isolate of F. varsavskyanum isolate had only one mating type idiomorph (MAT1-1 or MAT1-2), which suggests that the fungus is heterothallic. Genome sequence analysis indicated that F. varsavskyanum has the genetic potential to produce, (i) the emerging mycotoxins fusaric acid and beauvericin (or enniatins); (ii) the pigments bikaverin, carotenoids, and fusarubin; and (iii) the plant hormones auxins, cytokinins, and gibberellins. Thus, asymptomatic grasses from the Chaco wetland can harbor Fusarium species that in some agroecosystems can cause economically important diseases and/or mycotoxin contamination of crops. It remains to be determined whether the genotypes of Fusarium species that occur on the wetland grasses, including F. varsavskyanum genotypes, can negatively impact agriculture. Full article

Tung cake, a by-product of Vernicia fordii oil extraction, is an underutilized biomass residue rich in natural bioactive constituents and therefore shows potential for the development of sustainable protective formulations. In this study, tung cake-derived systems, including the aqueous extract, fermentation broth, and extract–ethanol mixtures with different ethanol volume fractions, were prepared and systematically evaluated as a unified protective system on two representative biological surfaces, namely rubberwood and fresh fruit. For rubberwood, the formulations were assessed in terms of uptake behavior, antifungal efficacy against Aspergillus niger, resistance to moisture swelling, and physicochemical characteristics using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). For fruit surfaces, preservation performance was evaluated through weight loss, decay rate, and color retention during storage. The results showed that formulation performance depended strongly on the preparation route and extract–ethanol mixture. In rubberwood, the 60–90% mixtures and the extract displayed showed better performance antifungal activity, with the 60%, 80%, and 90% mixtures reaching a control efficacy of 75.00% and the extract achieving 68.75%. The treatments also improved the dimensional stability of wood, and the water-saturated volumetric swelling rate decreased from 8.98% in the control to 5.63% in the extract-treated group. FTIR and XRD analyses indicated that the basic lignocellulosic chemical framework and cellulose-related diffraction features of rubberwood were largely retained after treatment, while treatment-dependent qualitative spectral and apparent diffraction differences were observed. SEM provided more direct evidence of surface-associated covering and reduced fungal attachment. A comparable protective tendency was also observed on fruit surfaces. In oranges, the 80% extract–ethanol mixture showed the most favorable preservation performance under the tested storage conditions, maintaining a decay rate of 0 throughout 10 days of storage, reducing weight loss to 17.76%, and preserving surface color more effectively than the control. Overall, the 80% ethanol mixture achieved the best balance between antimicrobial activity and barrier-related protection across both rubberwood and fruit surfaces. These findings demonstrate that tung cake waste can be converted into a bio-based protective system with potential mold-inhibiting and preservation functions across different biological substrates. Full article

Cultivable fungi are important components of freshwater ecosystems, yet their diversity in Amazonian aquatic environments remains poorly explored. This study evaluated cultivable fungal communities associated with water, sediment, and submerged wood in the Negro, Solimões, and Tapajós Rivers, representing the major black-, white-, and clear-water systems of the Amazon basin, respectively. Samples were collected along 25 m transects, fungi were isolated on potato dextrose agar, grouped into morphotypes, and identified morphologically. Diversity was assessed using richness, Shannon, Simpson, Pielou, and Sørensen indices. Overall, 130 isolates and 75 morphotypes were recorded, with a predominance of morphotypes assigned to filamentous Ascomycota and widespread occurrence of Aspergillus and Penicillium. Solid substrates yielded greater fungal abundance and richness than water samples. Submerged wood from the Negro River showed the highest overall cultivable fungal abundance, whereas the Tapajós River showed the highest diversity in water and sediment and the highest richness in both substrates. The Solimões River showed stronger dominance by a limited number of morphotypes, particularly in submerged wood. Sørensen similarity values indicated low compositional overlap among rivers, especially for submerged wood communities, suggesting apparent differentiation among river-associated cultivable fungal assemblages. Together, these exploratory results suggest that substrate type, hydrochemical differences, and potential temporal effects may be associated with the structure of cultivable fungal communities in Amazonian rivers. Full article

Ergosterol (ERG) is a bioactive sterol found in fungal cell membranes with reported cholesterol-lowering, antioxidant, and antitumor properties. Supercritical Fluid Extraction (SFE) conditions were optimized for Lentinula edodes (shiitake) using Response Surface Methodology and subsequently applied to Pleurotus ostreatus (oyster). Optimized SFE (690 bar, 69.8 °C, no co-solvent) produced significantly more concentrated ERG extracts than Soxhlet extraction for both species—280.57 ± 10.80 mg_ERG/g_extract for shiitake and 95.87 ± 7.18 mg_ERG/g_extract for oyster—corresponding to a 107% and 65% increase, respectively. Three biomass pre-treatments—ultrasound, microwave, and enzymatic—were evaluated in combination with SFE. Enzymatic pre-treatment with chitinase significantly improved ERG concentration: 337.53 ± 23.12 mg_ERG/g_extract for shiitake. These results obtained after analysis of samples by GC-MS demonstrate that high-pressure SFE combined with chitinase pre-treatment is an effective strategy for producing ERG-rich extracts from fungal matrices. Full article

Soil depth and habitat degradation can reshape fungal communities in salt-affected wetlands, but their effects on fungal ecological processes remain insufficiently understood. This study examined soil fungi in the Halahai Provincial Nature Reserve and adjacent converted farmland in the western Songnen Plain, Northeast China, where salt-affected meadow soils correspond mainly to Solonetz. Four habitat types—reed wetland, meadow steppe, degraded Suaeda saline patch, and converted farmland—were sampled at 0–20 cm and 20–40 cm soil depths. Soil properties, fungal diversity, taxonomic composition, environmental associations, niche breadth, assembly processes, and FUNGuild-based trophic modes were analyzed using ITS sequencing. Degraded Suaeda soils showed the strongest salinity–alkalinity stress, with pH values of 10.34–10.30 and electrical conductivity of 1.70–1.75 dS·m⁻¹. Fungal richness was highest in surface-converted farmland, with a Sobs value of 423.33, and lowest in deeper degraded Suaeda soil, with a Sobs value of 86.00. Ascomycota dominated most groups, especially degraded Suaeda soils, where its relative abundance reached 75.29–76.80%. ANOSIM confirmed significant community dissimilarity among habitat-depth groups (R = 0.56878, p = 0.001). Specialists accounted for 68.07% of fungal taxa, and stochastic processes, especially drift and dispersal limitation, contributed substantially to assembly. These results indicate that soil depth, salinity–alkalinity, and habitat conversion jointly regulate fungal community structure and ecological processes in degraded soda saline–alkali wetlands. Full article

Buds are a critical stage in the annual growth–dormancy cycle of perennial woody plants and are essential for survival and biomass accumulation. To safeguard these structures, trees employ both physical and chemical protection. Although Populus buds are known to contain rich phytochemistry, population-level variation remains largely unexplored. Here, we characterized bud phytochemistry across a population of Populus trichocarpa natural variants using gas chromatography–mass spectrometry and examined the antifungal properties of bud extracts. In the reference genotype Nisqually-1, a total of 32 lipophilic metabolites were detected, belonging to four chemical groups: terpenoids, phenylpropanoids, linear hydrocarbons, and others. Analysis of 49 additional P. trichocarpa natural variants revealed both shared features and substantial variation. All lines contained metabolites from the phenylpropanoid, linear hydrocarbon and terpenoid classes, which consistently dominated the profiles. However, quantitative differences in individual metabolites and relative class abundances distinguished the lines, allowing them to be grouped into three chemotypic clusters. To assess potential biological implications of phytochemical variance, we tested antifungal activity of bud extracts against the pathogenic fungus Fusarium oxysporum. Extracts from all 50 lines significantly inhibited fungal growth compared with controls. Correlation analyses between metabolite abundance and inhibition strength identified candidate metabolites that were most strongly associated with antifungal activity. Together, these findings reveal both conserved and variable components of bud phytochemistry in P. trichocarpa. The observed chemical diversity and consistent antifungal effects suggest that bud metabolites contribute to defense and may reflect adaptation across natural populations. Full article

This study examines the effects of climatic variability on bacterial and fungal populations, as well as enzymatic activities innutrient-rich, organic soils that support tea plants (Camellia sinensis L). Conducted from 2016 to 2019 across five district tea estates (TEs) in the Jorhat district of Assam, India, this research investigates the intricate relationships among these parameters. The findings indicate that bacterial and fungal communities exhibit optimal growth within a temperature range of 18 to 30 °C, establishing a critical threshold for their metabolic activity. A significant positive correlation was observed between the abundance of these microbial populations and the corresponding soil enzymatic activities, underscoring the essential role of these robust microbial communities in sustaining vital soil processes. Hierarchical cluster analysis identified two distinct groups of TEs that displayed consistent patterns of microbial behaviour across varying seasonal conditions. Furthermore, principal component analysis demonstrated that the first three principal components accounted for over 80% of the variability observed in the microbial and enzymatic data sets. This research contributes valuable insights into the dynamic interactions between seasonal fluctuations and soil health, highlighting the crucial contributions of bacterial and fungal populations, along with their enzymatic activities, to the complex ecosystem underlying tea cultivation. Full article

Organic-matter degradation and humification degree are key determinants of compost quality. In this study, we used pig manure and wheat straw to investigate the effects of diatomite on organic-component degradation, humification, and fungal community succession. In a 40-day aerobic composting experiment, we compared a control treatment with treatments supplemented with 4% and 8% diatomite. The results indicated that diatomite significantly accelerated organic-matter degradation and humification, with 8% diatomite increasing organic matter and lignin degradation by 9.05% and 9.27%, respectively. Based on linear interpolation of the HA/FA ratio dynamics, it was estimated that the maturity threshold (a ratio of humic acid to fulvic acid > 1.6) was reached 5–7 days earlier in the group subjected to 8% diatomite treatment relative to the control. Fungal community analysis revealed that the 8% diatomite treatment effectively alleviated fungal suppression under high-temperature conditions. By the maturation phase, fungal richness and diversity in the group subjected to the 8% diatomite treatment reached 1.8 and 2.6 times that of the control, respectively, significantly promoting the colonization and recovery of thermophilic Ascomycota, including Mycothermus and Aspergillus. Diatomite shifted fungal interactions from competition to symbiotic cooperation centered on Mycothermus, with partial least squares path modeling confirming fungal composition was a primary regulator of humification. This study demonstrates that 8% diatomite enhances composting efficiency and humification quality by optimizing fungal community structure and function, offering a theoretical and practical basis for the use of agricultural waste resources. Full article

Exogenous nutrient bags are essential for the artificial cultivation of Morchella sextelata, but the effects of different formulations on yield, nutritional quality, and the soil microecological environment remain unclear. In this study, nine exogenous nutrient bag formulations and one conventional treatment (CK) were evaluated during M. sextelata cultivation. Fruiting time, fresh and dry yields, and nutritional quality indicators were measured, and principal component analysis combined with membership function analysis was used for comprehensive evaluation. Soil physicochemical properties were determined for all treatments, and A7, A3, and CK were selected to represent the best-performing, worst-performing, and conventional treatments, respectively, for soil microbial community analysis. Different formulations significantly affected agronomic and nutritional traits (p < 0.01). A6 showed the shortest fruiting time and the highest fresh and dry yields, whereas A7 had the highest polysaccharide content and ranked first in the comprehensive evaluation. The D values of A7, A6, and CK were 0.789, 0.777, and 0.653, respectively. Soil nutrient analysis showed that morel cultivation markedly altered soil nutrient structure, especially available nutrients and phosphorus-related indicators. Microbial analysis showed that A7 had the highest bacterial richness among the three sequenced treatments and stronger colonization by M. sextelata. Its bacterial and fungal communities were also more closely associated with soil organic carbon. Overall, A6 was more suitable for yield-oriented production, whereas A7 showed the best comprehensive performance when yield, nutritional quality, and soil ecological characteristics were considered together. Full article