Search Results (73)

Fusarium diseases are among the most dangerous fungal diseases of plants. To date, there are no plant protectants that completely prevent fusariosis. Current breeding trends are therefore focused on increasing genetic resistance. While global modern maize breeding relies on various molecular genetics techniques, they are useless without a precise characterization of genomic regions that determine plant physiological responses to fungi. The aim of this study was thus to characterize the expression of candidate genes that were previously reported by our team as harboring markers linked to fusarium resistance in maize. The plant material included one susceptible and four resistant varieties. Biotic stress was induced in adult plants by inoculation with fungal spores under controlled conditions. qRT-PCR was performed. The analysis focused on four genes that encode for GDSL esterase/lipase (LOC100273960), putrescine hydroxycinnamyltransferase (LOC103649226), peroxidase 72 (LOC100282124), and uncharacterized protein (LOC100501166). Their expression showed differences between analyzed time points and varieties, peaking at 6 hpi. The resistant varieties consistently showed higher levels of expression compared to the susceptible variety, indicating their stronger defense responses. Moreover, to better understand the function of these genes, their expression in various organs and tissues was also evaluated using publicly available transcriptomic data. Our results are consistent with literature reports that clearly indicate the involvement of these genes in the resistance response to fusarium. Thus, they further emphasize the high usefulness of the previously selected markers in breeding programs to select fusarium-resistant maize genotypes. Full article

This study aims to identify the optimal conditions—host, plant material, seasonality, and agricultural practices—for isolating and developing a collection of culturable endophytic microorganisms to support sustainable Olea europaea L. cultivation. Samples were collected from three Sicilian olive cultivars (‘Nocellara del Belice’, ‘Nocellara Etnea’, and ‘Nocellara Messinese’) and six wild olive accessions across different phenological phases and under organic and conventional agronomic management. Endophytes were isolated from leaves and twigs using a culture-dependent approach, and their taxonomic diversity and plant-growth-promoting (PGP) traits were analyzed. A total of 133 endophytic isolates were identified, spanning bacterial (Proteobacteria, Firmicutes, and Actinobacteria) and fungal (Ascomycota and Basidiomycota) phyla. Wild olive trees contributed more than cultivated varieties to enriching the diversity and composition of culturable endophyte collection as well as twigs instead of leaves. Winter sampling allowed to implement the taxonomic genera of olive endophyte collection. Both farming systems favored an increase in the composition of microbial collection, though organic farming systems supported greater microbial richness. Functional analysis highlighted key PGP traits in a selection of bacterial isolates, including indole-3-acetic acid and siderophore production, nitrogen fixation, and antifungal activity. Bacillus spp. dominated enzymatic activities, such as amylase, protease, and lipase production, as well as antifungal activity against the olive fungal pathogen Neofusicoccum vitifusiforme. This research highlights the significant diversity and functional potential of Mediterranean olive endophytes. Our findings emphasize the role of native microbial communities as bio-inoculants, promoting plant growth, nutrient uptake, and disease resistance. These insights lay the groundwork for developing targeted olive-microbial consortia for biocontrol and stress tolerance applications. Full article

Nakaseomyces glabratus is an opportunistic fungal pathogen that primarily affects immunocompromised individuals. Unlike other Candida species, N. glabratus exhibits nondimorphic blastoconidial morphology and a haploid genome. It is a leading cause of both superficial (oral, esophageal, vaginal, or urinary) and systemic candidiasis. In this study, we evaluated 47 clinical isolates from Central Bulgaria (Plovdiv) and 1 wild strain isolated from the gut of the beetle Oxythyrea funesta (Coleoptera: Cetoniinae) collected in Sofia, Bulgaria. Growth was observed across a pH range of 3 to 9. The strains were assessed for the production of lipases, esterases, and proteases—enzymes associated with pathogenicity—and their relationship to virulence. Biofilm formation and exopolysaccharide production were also measured, with all strains showing similar profiles. No competitive inhibition of N. glabratus was observed against C. parapsilosis. All isolates exhibited resistance to micafungin, while resistance to both micafungin and anidulafungin was observed in 21 isolates (44%). These findings provide insight into the biochemical characteristics of N. glabratus populations from Southeast Europe, contributing to a better understanding of strain behavior under controlled laboratory conditions and addressing the gap in data on this species in the region. Full article

Plant-associated bacteria play a crucial role in protecting plants from pathogens, yet the diversity and antagonistic potential of these bacteria across different plant species remain underexplored, especially in central Asia. To investigate the competitive dynamics between phytopathogenic fungi and plant-associated bacteria, we collected stem and root samples from 50 plant species across nine regions of Uzbekistan. A total of 3355 bacterial isolates were obtained (1896 from roots and 1459 from shoots) and screened for antifungal activity against six fungal pathogens, resulting in 432 antagonistic isolates. These were identified through 16S rDNA sequencing, revealing 65 bacterial species across three phyla: Firmicutes, Proteobacteria, and Actinobacteria, predominantly in the respective families Bacillaceae, Pseudomonadaceae, and Caryophanaceae. The plant Salsola vvedenskii hosted the highest diversity of antagonists (26 species), while other species harbored fewer. Plant species showed strong associations with specific bacterial communities, with 14 plant species each hosting unique antagonists. Enzymatic profiling revealed functional diversity, with Bacillus species producing protease, cellulase, and lipase activities, while Pseudomonas species excelled in xylanase, glucanase, and cellobiase production. B. mojavensis 9r-29 stood out by producing all six enzymes. These findings underscore the ecological diversity and biocontrol potential of plant-associated bacteria in natural ecosystems, offering promising candidates for sustainable plant protection strategies. Full article

Post-harvest decay of Carica papaya L. is the primary cause of deterioration in papaya quality and the low economic impact of this sector in Cameroon. Field surveys conducted by teams from the Ministry of Agriculture and Rural Development (MINADER) in Cameroon have primarily associated these decays with fungal attacks. However, to date, no methodological analysis has been conducted on the identification of these fungal agents. To reduce post-harvest losses, rapid detection of diseases is crucial for the application of effective management strategies. This study sought to identify the fungal agents associated with post-harvest decay of papaya cv Sunrise solo in Cameroon and to determine their physiological and biochemical growth characteristics. Isolation and pathogenicity tests were performed according to Koch’s postulate. Molecular identification of isolates was achieved by amplification and sequencing of the ITS1 and ITS4 regions. Phylogenetic analysis was based on the substitution models corresponding to each fungal genus determined by jModeltest, according to the Akaike information criterion (AIC). Fungal explants of each identified species were subjected to variations in temperature, pH, water activity, and NaCl concentration. The ability to secrete hydrolytic enzymes was determined on specific media such as skimmed milk agar for protease, peptone agar for lipase, and carboxymethylcellulose for cellulase. These experiments allowed the identification of three fungi responsible for papaya fruit decay, namely Colletotrichum gloeosporioides, Fusarium equiseti, and Lasiodiplodia theobromae. All three pathogens had maximum mycelial growth at a temperature of 25 ± 2 °C, pH 6.5, NaCl concentration of 100 µM, and water activity (aw) equal to 0.98. The three fungal agents demonstrated a strong potential for secreting cellulases, lipases, and proteases, which they use as lytic enzymes to degrade papaya tissues. The relative enzymatic activity varied depending on the fungal pathogen as well as the type of enzyme secreted. This study is the first report of F. equiseti as a causal agent of papaya fruit decay in Cameroon. Full article

The improper discharge of wastewater has increased the presence of pollutants, among which lipids are particularly problematic. These compounds form oily layers that hinder oxygen transfer and sunlight penetration, negatively impacting aquatic ecosystems. Conventional methods for treating such effluents are often costly and environmentally unfriendly. In this context, bioremediation using lipases, such as those produced by Penicillium rubens LBM 081, represents an effective and sustainable alternative. This study evaluated the biotechnological potential of the lipase from P. rubens LBM 081 for the hydrolysis of lipid-rich wastewater. Lipase activity was influenced by the carbon and nitrogen sources in the culture medium, reaching maximum activity (2780 U mL⁻¹) under optimal conditions of 2% meat peptone, 4% olive oil, a spore concentration of 1 × 10⁶, incubation at 30 °C, and agitation at 140 rpm. The optimized enzymatic supernatant significantly reduced COD, oils, and total fats in the effluents. Furthermore, GC-MS analysis revealed a significant increase in free fatty acids, confirming triglyceride hydrolysis. These results highlight the potential of P. rubens LBM 081 lipase as an effective and environmentally sustainable biotechnological alternative for the treatment of lipid-rich wastewater. Full article

Plastic, a ubiquitous part of our daily lives, has become a global necessity, with annual production exceeding 300 million tons. However, the accumulation of synthetic polymers in our environment poses a pressing global challenge. To address this urgent issue, fungi have emerged as potential agents for plastic degradation. In our previous manuscript, ‘A Review of the Fungi That Degrade Plastic’, we explored the taxonomic placement of plastic-degrading fungi across three main phyla: Ascomycota, Basidiomycota, and Mucoromycota. In this review, we built upon that foundation and aimed to further explore the taxonomic relationships of these fungi in a comprehensive and detailed manner, leaving no stone unturned. Moreover, we linked metabolic activity and enzyme production of plastic-degrading fungi to their taxonomy and summarized a phylogenetic tree and a detailed table on enzyme production of plastic-degrading fungi presented here. Microbial enzymes are key players in polymer degradation, operating intra-cellularly and extra-cellularly. Fungi, one of the well-studied groups of microbes with respect to plastic degradation, are at the forefront of addressing the global issue of plastic accumulation. Their unique ability to hydrolyze synthetic plastic polymers and produce a wide range of specific enzymes is a testament to their potential. In this review, we gather and synthesize information concerning the metabolic pathways of fungi involved in the degradation of plastics. The manuscript explores the diverse range of specific enzymes that fungi can produce for plastic degradation and the major pathways of plastic metabolism. We provide a listing of 14 fungal enzymes (Esterase, Cutinase, Laccase, Peroxidases, Manganese peroxidase, Lignin peroxidase, Oxidoreductases, Urease, Protease, Lipase, Polyesterase, Dehydrogenase, Serine hydrolase, and PETase) involved in pathways for plastic degradation alongside the relevant fungi known to produce these enzymes. Furthermore, we integrate the fungi’s enzyme-producing capabilities with their taxonomy and phylogeny. Taxonomic and phylogenetic investigations have pinpointed three primary fungal classes (Eurotiomycetes, Sordariomycetes (Ascomycota), and Agaricomycetes (Basidiomycota)) as significant plastic degraders that produce the vital enzymes mentioned earlier. This paper provides a foundational resource for recognizing fungal involvement in the biodegradation of synthetic polymers. It will ultimately advance fungal biotechnology efforts to address the global issue of plastic accumulation in natural environments. Full article

The study of the fungal communities of the skin constitutes a pivotal component of skin microbiome research. Within these communities, the genus Malassezia stands out as a major constituent, representing 50% to 80% of the total fungal colonization on the skin of healthy individuals. The excessive growth or metabolic irregularities of this genus are intimately connected with the onset of various skin disorders that are intrinsically linked to its lipid-dependent nature. Cutaneous lipid metabolism is indispensable for maintaining the skin barrier function and skin health. Malassezia possesses the ability to encode multiple lipase genes, and the secretion of these lipases plays a pivotal role in the survival strategies of the fungi. This review explores recent advances in the ecological niche of Malassezia in skin microecological homeostasis, its mechanism of disrupting skin lipids through catabolic metabolites, and the relationship between this disruption of the skin lipid barrier and skin diseases. This review offers a reference for future research on the mechanisms by which Malassezia affects lipid metabolism and provides a theoretical foundation for the development of innovative therapeutic approaches for dermatological conditions. Full article

Esters are vital flavor compounds in Chinese Nongxiangxing baijiu and greatly affect the quality of baijiu. Microbial communities inhabiting fermented grains (FGs) have a marked impact on esters. However, the specific microorganisms and their assembly patterns remain unclear. This study utilized high-throughput sequencing and a culture-based method to reveal ester-producing microorganisms. A total of 33 esters were detected, including 19 ethyl esters, 9 linear chain esters, and 2 branched chain esters. A correlation analysis indicated that the bacterial genus Lactobacillus (relative abundance in average: 69.05%) and fungal genera Pichia (2.40%), Aspergillus (11.84%), Wickerhamomyces (0.60%), Thermomyces (3.57%), Saccharomycopsis (7.87%), Issatchenkia (0.96%), and Thermoascus (10.83%) were dominant and associated with esters production and their precursors. The numbers of esters positively correlated with them were 1, 17, 3, 2, 1, 1, 1, and 1, respectively. The modified stochasticity ratio (MST) index and Sloan neutral model revealed that bacteria were predominantly governed by deterministic processes while fungal assemblies were more stochastic. Saturnispora silvae and Zygosaccharomyces bailii were isolated and identified with ester synthesis potential. PICRUSt2 analysis showed that fungi in FG had a high potential for synthesizing ethanol, while 14 enzymes related to esters synthesis were all produced by bacteria, especially enzymes catalyzing the synthesis of acyl-CoA. In addition, ester synthesis was mainly catalyzed by carboxylesterase, acylglycerol lipase and triacylglycerol lipase. These findings may provide insights into ester production mechanism and potential strategies to improve the quality of Nongxiangxing baijiu. Full article

Fungal diseases not only reduce the yield of edible mushrooms but also pose potential threats to the preservation and quality of harvested mushrooms. Cobweb disease, caused primarily by fungal pathogens from the Hypocreaceae family, is one of the most significant diseases affecting edible mushrooms. Deciphering the genomes of these pathogens will help unravel the molecular basis of their evolution and identify genes responsible for pathogenicity. Here, we present high-quality genome sequences of three cobweb disease fungi: Hypomyces aurantius Cb-Fv, Cladobotryum mycophilum CB-Ab, and Cladobotryum protrusum CB-Mi, isolated from Flammulina velutipes, Agaricus bisporus, and Morchella importuna, respectively. The assembled genomes of H. aurantius, C. mycophilum, and C. protrusum are 33.19 Mb, 39.83 Mb, and 38.10 Mb, respectively. This is the first report of the genome of H. aurantius. Phylogenetic analysis revealed that cobweb disease pathogens are closely related and diverged approximately 17.51 million years ago. CAZymes (mainly chitinases, glucan endo-1,3-beta-glucosidases, and secondary metabolite synthases), proteases, KP3 killer proteins, lipases, and hydrophobins were found to be conserved and strongly associated with pathogenicity, virulence, and adaptation in the three cobweb pathogens. This study provides insights into the genome structure, genome organization, and pathogenicity of these three cobweb disease fungi, which will be a valuable resource for comparative genomics studies of cobweb pathogens and will help control this disease, thereby enhancing mushroom quality. Full article

The slow action of fungi is one of the biggest challenges in using entomopathogenic fungi. A promising alternative to reduce the time of action is to combine conidia with extracellular enzymes. This study aimed to characterize the production of Pr1 subtilisin protease and lipases by Beauveria bassiana and Metarhizium anisopliae in different culture media and to evaluate the efficiency of the enzymatic treatment against Aphis gossypii and Spodoptera frugiperda. The isolates were cultivated in five different liquid cultures, and, after 7 days, the culture was filtered and centrifuged, and the activity of the Pr1 and lipases was measured. The fungi cultured in a Luria–Bertani broth medium had the highest activity of proteases and lipases. The mortality of A. gossypii nymphs treated with conidia 7 days after the treatment was 39% (JEF-410), 76.5% (JEF-492), 74.8% (ERL-836), and 70.9% (JEF-214). The B. bassiana JEF-410 supernatant combined with conidia increased the fungal virulence at day 5 and day 6 after treatment. When S. frugiperda larvae were treated with B. bassiana JEF-492 conidia combined with its supernatant, the time of infection was shorter compared to the larvae treated with conidia only. Once the supernatant was incubated at 37 °C, the relative activity decreased from 100% to 80% after 2 h and to 45% after 24 h. The results suggest that the supernatant of entomopathogenic fungi may be formulated and used as a biopesticide in an efficient strategy for the biological control of pests. Full article

This study assessed the application of whole lipolytic cells in the pretreatment of slaughterhouse wastewater to reduce its lipid content. The fungal biomass of Rhizopus oryzae was evaluated in the hydrolysis of slaughterhouse wastewater containing high lipid concentrations, focusing on the biomass’s concentration and the effect of using an emulsifier and surfactant. The use of the whole-cells lipase of Rhizopus oryzae grown in a residual vegetable oil medium proved effective in the hydrolysis of slaughterhouse wastewater, generating concentrations of free fatty acids (FFA) ranging from 40.36 to 90.14 mM. The action of lipase in the hydrolysis of slaughterhouse residues indicated its effectiveness in pretreating lipid-rich liquid residues, potentially boosting the microbiota of this anaerobic treatment. The results showed that lipase activity without surfactant exhibited a similar performance to that of Triton X-100 in the hydrolysis of liquid residues. However, the combination of lipase and surfactant could represent a promising strategy to optimize free fatty acid production from slaughterhouse residues, strengthening anaerobic treatment processes and potentially enhancing the overall efficiency of waste management systems. Full article

Skin microbiota, such as acne-related Cutibacterium acnes, Staphylococcus aureus, and fungal Candida albicans, can form polymicrobial biofilms with greater antimicrobial tolerance to traditional antimicrobial agents and host immune systems. In this study, the phytopigment shikonin was investigated against single-species and multispecies biofilms under aerobic and anaerobic conditions. Minimum inhibitory concentrations of shikonin were 10 µg/mL against C. acnes, S. aureus, and C. albicans, and at 1–5 µg/mL, shikonin efficiently inhibited single biofilm formation and multispecies biofilm development by these three microbes. Shikonin increased porphyrin production in C. acnes, inhibited cell aggregation and hyphal formation by C. albicans, decreased lipase production, and increased hydrophilicity in S. aureus. In addition, shikonin at 5 or 10 µg/mL repressed the transcription of various biofilm-related genes and virulence-related genes in C. acnes and downregulated the gene expression levels of the quorum-sensing agrA and RNAIII, α-hemolysin hla, and nuclease nuc1 in S. aureus, supporting biofilm inhibition. In addition, shikonin prevented multispecies biofilm development on porcine skin, and the antimicrobial efficacy of shikonin was recapitulated in a mouse infection model, in which it promoted skin regeneration. The study shows that shikonin inhibits multispecies biofilm development by acne-related skin microbes and might be useful for controlling bacterial infections. Full article

Even though fungi are ubiquitous in the biosphere, the ecological knowledge of marine fungi remains rather rudimentary. Also, little is known about their tolerance to salinity and how it influences their activities. Extracellular enzymatic activities (EEAs) are widely used to determine heterotrophic microbes’ enzymatic capabilities and substrate preferences. Five marine fungal species belonging to the most abundant pelagic phyla (Ascomycota and Basidiomycota) were grown under non-saline and saline conditions (0 g/L and 35 g/L, respectively). Due to their sensitivity and specificity, fluorogenic substrate analogues were used to determine hydrolytic activity on carbohydrates (β-glucosidase, β-xylosidase, and N-acetyl-β-D-glucosaminidase); peptides (leucine aminopeptidase and trypsin); lipids (lipase); organic phosphorus (alkaline phosphatase), and sulfur compounds (sulfatase). Afterwards, kinetic parameters such as maximum velocity (V_max) and half-saturation constant (K_m) were calculated. All fungal species investigated cleaved these substrates, but some species were more efficient than others. Moreover, most enzymatic activities were reduced in the saline medium, with some exceptions like sulfatase. In non-saline conditions, the average V_max ranged between 208.5 to 0.02 μmol/g biomass/h, and in saline conditions, 88.4 to 0.02 μmol/g biomass/h. The average K_m ranged between 1553.2 and 0.02 μM with no clear influence of salinity. Taken together, our results highlight a potential tolerance of marine fungi to freshwater conditions and indicate that changes in salinity (due to freshwater input or evaporation) might impact their enzymatic activities spectrum and, therefore, their contribution to the oceanic elemental cycles. Full article

When replanting an asparagus field, the roots of the previous crop are crushed and incorporated into the soil, creating problems of autotoxicity and fungal infections. Asparagus roots can be considered as a valuable byproduct, since they are very rich in saponins (3–6%), compounds currently considered as bio-emulsifiers. The objective is to evaluate the emulsifying and foaming capacity of a saponin extract from asparagus roots (ARS) and compare it with other commercial extracts. ARS was obtained using a process patented by our research group. The results have shown that ARS has activity similar to Quillaja extract. Its critical micellar concentration falls between that of Quillaja and Tribulus extracts (0.064, 0.043, and 0.094 g/100 mL, respectively). Both emulsifying and foaming activities are affected by pH, salt, and sucrose to a similar extent as the other extracts. Additionally, it has demonstrated an inhibitory effect on pancreatic lipase, which is even better than the other two studied extracts, as indicated by its IC₅₀ value (0.7887, 1.6366, and 2.0107 mg/mL for asparagus, Quillaja, and Tribulus, respectively). These results suggest that ARS could serve as a natural emulsifying/foaming agent for healthier and safer food products and as a potential aid in treatments for obesity and hyperlipidemia. Full article