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Journal of Fungi (Basel, Switzerland) May 2024Autophagy, a conserved cellular recycling process, plays a crucial role in maintaining homeostasis under stress conditions. It also regulates the development and...
Autophagy, a conserved cellular recycling process, plays a crucial role in maintaining homeostasis under stress conditions. It also regulates the development and virulence of numerous filamentous fungi. In this study, we investigated the specific function of ATG8, a reliable autophagic marker, in the opportunistic pathogen . To investigate the role of in , the deletion and complemented mutants of were generated according to the homologous recombination principle. Deletion of showed a significant decrease in conidiation, spore germination, and sclerotia formation compared to the WT and strains. Additionally, aflatoxin production was found severely impaired in the ∆ mutant. The stress assays demonstrated that ATG8 was important for response to oxidative stress. The fluorescence microscopy showed increased levels of reactive oxygen species in the ∆ mutant cells, and the transcriptional result also indicated that genes related to the antioxidant system were significantly reduced in the ∆ mutant. We further found that ATG8 participated in regulating the pathogenicity of on crop seeds. These results revealed the biological role of ATG8 in , which might provide a potential target for the control of and AFB1 biosynthesis.
PubMed: 38786704
DOI: 10.3390/jof10050349 -
Journal of Fungi (Basel, Switzerland) Apr 2024The tomato ( Mill.) is considered to be one of the products with the highest demand due to its nutritional value; however, it is susceptible to infection by fungi during...
The tomato ( Mill.) is considered to be one of the products with the highest demand due to its nutritional value; however, it is susceptible to infection by fungi during its pre- and postharvest stages. In this research, three commercial products (1% Citrocover, 1% Citro 80, and 0.002% Microdyn) and two coatings based on 1.0% chitosan/0.1% lime or 0.1% orange essential oils were evaluated in vitro and on Saladette tomatoes that were previously inoculated with four postharvest fungi. The application of the commercial citrus-based product Citrocover was highly effective in reducing the in vitro development of , , and , but not . The sanitizer Microdyn promoted infections with most fungi. Citrus-based products were effective in reducing infections with in the tomatoes during storage. Overall, mycotoxin production was very low for all treatments. The use of commercial citrus-based products and coatings did not alter the weight loss, firmness, or total soluble solid contents of the treated tomatoes. The changes observed were, rather, associated with the normal ripening process of Saladette tomatoes. The commercial citrus-based products satisfactorily controlled the in vitro growth of the fungi , , and .
PubMed: 38786664
DOI: 10.3390/jof10050309 -
Antibiotics (Basel, Switzerland) May 2024Simple low-cost, nontoxic, environmentally friendly plant-extract-based polymer films play an important role in their application in medicine, the food industry, and...
Simple low-cost, nontoxic, environmentally friendly plant-extract-based polymer films play an important role in their application in medicine, the food industry, and agriculture. The addition of silver nanoparticles to the composition of these films enhances their antimicrobial capabilities and makes them suitable for the treatment and prevention of infections. In this study, polymer-based gels and films (AgRonPVA) containing silver nanoparticles (AgNPs) were produced at room temperature from fresh red onion peel extract ("Ron"), silver nitrate, and polyvinyl alcohol (PVA). Silver nanoparticles were synthesized directly in a polymer matrix, which was irradiated by UV light. The presence of nanoparticles was approved by analyzing characteristic local surface plasmon resonance peaks occurring in UV-Vis absorbance spectra of irradiated experimental samples. The proof of evidence was supported by the results of XRD and EDX measurements. The diffusion-based method was applied to investigate the antimicrobial activity of several types of microbes located in the environment of the produced samples. Bacteria ATCC 29213, ATCC BAA 747, and ATCC 15442; yeasts CBS 8836 and ATCC 90028; and microscopic fungi assays BTL G-33 and BTL G-38 were used in this investigation. The greatest effect was observed on Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa bacteria, defining these films as potential candidates for antimicrobial applications. The antimicrobial features of the films were less effective against fungi and the weakest against yeasts.
PubMed: 38786169
DOI: 10.3390/antibiotics13050441 -
Journal of the Science of Food and... May 2024The recurrent contaminations of feed materials with mycotoxigenic fungi can endanger both farmed animals and humans. Biosynthesized nanomaterials are assumingly the...
BACKGROUND
The recurrent contaminations of feed materials with mycotoxigenic fungi can endanger both farmed animals and humans. Biosynthesized nanomaterials are assumingly the ideal agents to overcome fungal invasion in feed/foodstuffs, especially when utilizing sustainable sources for synthesis. Herein, the phycosynthesis of selenium nanoparticles (SeNPs) was targeted using Cystoseira myrica algal extract (CE), and the conjugation of CE/SeNPs with chitosan nanoparticles (NCt) to produce potential antifungal nanocomposites for controlling Aspergillus flavus isolates in fish feed.
RESULTS
The phycosynthesis of SeNPs with CE was effectually carried out and validated using visible/UV analysis, X-ray diffraction and transmission microscopy; CE/SeNPs had diameters of 8.7 nm and spherical shapes. NCt/CE/SeNPs nanocomposite (173.3 nm mean diameter) was achieved and the component interactions were validated via infrared spectroscopic analysis. The antifungal assessment of screened nanomaterials against three Aspergillus flavus strains indicated that NCt/CE/SeNPs exceeded the fluconazole action using qualitative/quantitative assays. Severe alteration/distortions in A. flavus mycelial structure and morphology were microscopically observed within 48 h of NCt/CE/SeNPs treatment. The treatment of feed ingredients (crushed corn and feed powder) by blending with nanomaterials (NCt, CE/SeNPs and NCt/CE/SeNPs) led to significant reduction in A. flavus count/growth after storage for 7 days; NCt/CE/SeNPs could completely inhibit any fungal growth in feed material.
CONCLUSION
The pioneering phycosynthesis of CE/SeNPs and their nanoconjugation with NCt generated bioactive antifungal agents to control A. flavus strains. The innovatively constructed NCt/CE/SeNPs nanocomposite is advised for application as an effectual, biosafe and natural fungicidal conjugate for the protection of fish feed from mycotoxigenic fungi. © 2024 Society of Chemical Industry.
PubMed: 38775588
DOI: 10.1002/jsfa.13604 -
AMB Express May 2024The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy,...
The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with - 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46-53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms.
PubMed: 38761277
DOI: 10.1186/s13568-024-01707-2 -
International Journal of Food... Jun 2024Aspergillus flavus is a notorious fungus that contaminates food crops with toxic aflatoxins, posing a serious threat to human health and the agricultural economy. To...
Aspergillus flavus is a notorious fungus that contaminates food crops with toxic aflatoxins, posing a serious threat to human health and the agricultural economy. To overcome the inadequacy of traditional control methods and meet consumer preferences for natural-sources additives, there is an urgent demand for novel biocontrol agents that are safe and efficient. This study aims to investigate the antifungal properties of a novel antifungal agent derived from the biologically safe Lactiplantibacillus plantarum WYH. Firstly, antifungal peptides (AFPs) with a molecular weight of less than 3kD, exhibiting remarkable temperature stability and effectively retarding fungal growth in a dose-dependent manner specifically against A. flavus, were concentrated from the fermentation supernatant of L. plantarum WYH and were named as AFPs-WYH. Further analysis demonstrated that AFPs-WYH might exert antifungal effects through the induction of oxidative stress, disruption of mitochondrial function, alteration of membrane permeability, and cell apoptosis in A. flavus. To further validate our findings, a transcriptomics analysis was conducted on A. flavus treated with 2 and 5 mg/mL of AFPs-WYH, which elucidated the potential effect of AFPs-WYH administration on the regulation of genes involved in impairing fungal development and preventing aflatoxin biosynthesis pathways. Overall, AFPs-WYH reduced the A. flavus proliferation and affected the AFB biosynthesis, exhibiting a promising potential for food industry applications as a biopreservative and biocontrol agent.
Topics: Aspergillus flavus; Antifungal Agents; Biological Control Agents; Food Contamination; Lactobacillus plantarum; Fermentation; Peptides; Aflatoxins; Oxidative Stress
PubMed: 38759292
DOI: 10.1016/j.ijfoodmicro.2024.110727 -
Designed Monomers and Polymers 2024A new class of biologically active polyazomethine/pyrazole and their related nanocomposites, polyazomethine/pyrazole/zinc oxide nanoparticles, have been successfully...
A new class of biologically active polyazomethine/pyrazole and their related nanocomposites, polyazomethine/pyrazole/zinc oxide nanoparticles, have been successfully synthesized through the polycondensation technique in the form of polyazomethine pyrazole (PAZm/Py) and polyazomethine/pyrazole/zinc oxide nanoparticles (PAZm/Py/ZnO). The polymeric nanocomposites were prepared with a 5% loading of zinc oxide nanofiller using the same preparation technique, in addition to the help of ultrasonic radiation. The characteristics of the new polymers, such as solubility, viscometry, and molecular weight, were examined. All the polymers were completely soluble in the following solvents: concentrated sulfuric acid, formic acid, dimethylformamide, dimethyl sulfoxide, and tetrahydrofuran. Furthermore, the weight loss of the polyazomethine pyrazole (4, 5, and 6) at 800 °C was 67%, 95%, and 86%, respectively, which indicates the thermal stability of these polymers. At 800 °C, the polyazomethine/pyrazole/zinc oxide nanoparticles (a, b, and c) lost 74%, 68%, and 75% of their weight, respectively. This shows that adding zinc oxide nanoparticles made these compounds more stable at high temperatures. The X-Ray diffraction pattern of the polyazomethine pyrazole (PAZm/Py) shows a number of sharp peaks with varying intensities. The polymers that were studied had straight crystal structures. Furthermore, the measurements of polyazomethine/pyrazole/zinc oxide nanoparticles (PAZm/Py/ZnO) indicate a good merging of zinc oxide nanoparticles into the matrix of polymers. The antimicrobial activity of polymers and polymer nanocomposites was tested against some selected bacteria and fungi. The synthesized polymer (c) shows the highest activity against the two types of gram-negative bacteria selected. Most tested compounds were found to be effective against gram-positive bacteria except polyazomethine pyrazole (PAZm/Py) and polyazomethine pyrazole (PAZm/Py), which do not exhibit any activity. The synthesized polymers and their related nanocomposites were tested for their ability to kill the chosen fungi. All of them were effective against Aspergillus flavus, but only polyazomethine pyrazole (PAZm/Py) and polyazomethine/pyrazole/zinc oxide (PAZm/Py/ZnO) were effective against Candida albicans.
PubMed: 38756722
DOI: 10.1080/15685551.2024.2352897 -
Allergologie Select 2024None.
None.
PubMed: 38756207
DOI: 10.5414/ALX02444E -
World Journal of Microbiology &... May 2024Jojoba shrubs are wild plants cultivated in arid and semiarid lands and characterized by tolerance to drought, salinity, and high temperatures. Fungi associated with...
Jojoba shrubs are wild plants cultivated in arid and semiarid lands and characterized by tolerance to drought, salinity, and high temperatures. Fungi associated with such plants may be attributed to the tolerance of host plants against biotic stress in addition to the promotion of plant growth. Previous studies showed the importance of jojoba as jojoba oil in the agricultural field; however, no prior study discussed the role of jojoba-associated fungi (JAF) in reflecting plant health and the possibility of using JAF in biocontrol. Here, the culture-independent and culture-dependent approaches were performed to study the diversity of the jojoba-associated fungi. Then, the cultivable fungi were evaluated for in-vitro antagonistic activity and in vitro plant growth promotion assays. The metagenome analysis revealed the existence of four fungal phyla: Ascomycota, Aphelidiomycota, Basidiomycota, and Mortierellomycota. The phylum Ascomycota was the most common and had the highest relative abundance in soil, root, branch, and fruit samples (59.7%, 50.7%, 49.8%, and 52.4%, respectively). Alternaria was the most abundant genus in aboveground tissues: branch (43.7%) and fruit (32.1%), while the genus Discosia had the highest abundance in the underground samples: soil (24%) and root (30.7%). For the culture-dependent method, a total of 14 fungi were isolated, identified, and screened for their chitinolytic and antagonist activity against three phytopathogenic fungi (Fusarium oxysporum, Alternaria alternata and Rhizoctonia solani) as well as their in vitro plant growth promotion (PGP) activity. Based on ITS sequence analysis, the selected potent isolates were identified as Aspergillus stellatusEJ-JFF3, Aspergillus flavus EJ-JFF4, Stilbocrea sp. EJ-JLF1, Fusarium solani EJ-JRF3, and Amesia atrobrunneaEJ-JSF4. The endophyte strain A. flavus EJ-JFF4 exhibited the highest chitinolytic activity (9 Enzyme Index) and antagonistic potential against Fusarium oxysporum, Alternaria alternata, and Rhizoctonia solani phytopathogens with inhibitory percentages of 72, 70, and 80 respectively. Also, A. flavus EJ-JFF4 had significant multiple PGP properties, including siderophore production (69.3%), phosphate solubilization (95.4 µg ml). The greatest production of Indol-3-Acetic Acid was belonged to A. atrobrunnea EJ-JSF4 (114.5 µg ml). The analysis of FUNGuild revealed the abundance of symbiotrophs over other trophic modes, and the guild of endophytes was commonly assigned in all samples. For the first time, this study uncovered fungal diversity associated with jojoba plants using a culture-independent approach and in-vitro assessed the roles of cultivable fungal strains in promoting plant growth and biocontrol. The present study indicated the significance of jojoba shrubs as a potential source of diverse fungi with high biocontrol and PGP activities.
Topics: Fungi; Alternaria; Soil Microbiology; Metagenome; Rhizoctonia; Phylogeny; Plant Diseases; Fusarium; Antibiosis; Plant Roots; Biodiversity; Biological Control Agents; Ascomycota; Plant Development
PubMed: 38755302
DOI: 10.1007/s11274-024-03986-0 -
Biomedical Chromatography : BMC Jul 2024Spices are food flavouring agents that are highly used in Iraq. However, they may be contaminated by toxicogenic fungi and subsequent production of mycotoxins. The aim...
Spices are food flavouring agents that are highly used in Iraq. However, they may be contaminated by toxicogenic fungi and subsequent production of mycotoxins. The aim of this study was to investigate the contamination of commonly used spices with fungi using polymerase chain reaction (PCR) assay and to detect fungal mycotoxin using high-performance liquid chromatography. Thirty-five spices (seven samples from each black pepper, red pepper, turmeric, cumin and ginger) were cultured on an appropriate medium to identify various fungi species. Later on, the toxigenicity of Aspergillus flavus and Aspergillus niger was determined using a PCR assay. The fungal mycotoxins, including aflatoxins and ochratoxins, were then determined through a high-performance liquid chromatography using the validated Quick, Easy, Cheap, Effective, Rugged, and Safe (QuECHERS) method. Aspergillus species were the predominantly isolated fungi, followed by Penicillium and Fusarium. The PCR results indicate the high toxigenicity of A. flavus as 85.7% of the strains had aflQ/aflR genes and 79% had PKS15KS/PKS15C-MeT genes. Regarding mycotoxin contamination in spices, the highest rates of aflatoxins and ochratoxins were found in black pepper (5.913 μg/kg) and red chilli (6.9055 μg/kg), respectively. Spices are susceptible substrates for the growth of mycotoxigenic fungi. Thus, regular effective surveillance and quality control procedures are highly recommended.
Topics: Spices; Mycotoxins; Chromatography, High Pressure Liquid; Fungi; Reproducibility of Results; Limit of Detection; Polymerase Chain Reaction; Linear Models
PubMed: 38752546
DOI: 10.1002/bmc.5889