Strains Of Aspergillus Flavus Research Articles

Comparative impacts of myco-synthesized nanoparticles against strains of Aspergillus spp. causing biodeterioration of stored cocoa beans in Nigeria

Silver nanoparticle solutions (AgNPs) of some mushrooms: Pleurotus ostreatus, Agaricus bisporus and Agaricus campestris were prepared and characterized using Transmission Electron Microscopy (TEM), Fourier-Transform Infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD) analysis and Energy Dispersive X-ray (EDX) spectroscopy. Each of the myco-sythesized AgNPs was plated against strains of Aspergillus flavus and A. ochraceous, at 5, 10 and 15% concentrations. Colour change from light yellow to orange, yellowish-brown, and reddish brown was observed after overnight incubation (at 28 °C), in the P. ostreatus, A. bisporus, and A. campestris synthesized AgNPs respectively. TEM analysis showed a spherical shape with an average size of 15.25 to 45.85 nm, 9.22 to 52.60 nm and 10.24 to 17.66 nm in P. ostreatus, A. campestris and A. bisporus AgNPs respectively. EDX spectrum showed absorption peaks of silver in the ranges of 0.8–1.4 keV, 6.2–6.6 keV, and 0.8–1.2 keV, and XRD analysis confirmed the crystalline structure of the biosynthesized AgNPs, while FTIR results revealed O–H, N–H, C=O, and C=N as the prominent functional groups. Mycelial inhibitions against A. flavus strains D28AF and D42AF ranged between 43.86–52.73% and 33.83–57.07% respectively, and were not significantly different (P ≤ 0.05) from the standard (copper sulphate). Inhibitions produced against A. ochraceous strains AOD40 and AOD45 ranged between 34.64–52.36% and 37.43–53.56% respectively and also showed similar trend in relation to the standard. This study showed that the myco-synthesized AgNPs were effective against A. flavus and A. ochraceous infecting cocoa beans at storage. They however need to be further improved for future use in the control of cocoa beans pathogens.

Study on the ability to inhibit the growth and aflatoxin B1 production from Aspergillus flavus using some essential oils

Vietnam is a country with favorable natural conditions for growing vegetables containing essential oils such as marjoram, dill, lemon basil, perilla, coriander and onions. The objective of this study was to evaluate the inhibition of growth and aflatoxin production in the Aspergillus flavus strain by various essential oils in a culture medium. Samples of marjoram essential oil, dill essential oil, lemon basil essential oil, perilla essential oil, coriander essential oil and onion essential oil were tested for their effects on mycelial growth and aflatoxin production. The findings of this study revealed the antifungal efficacy of all the tested essential oils. The extent of inhibition of fungal growth and aflatoxin production was dependent on the type and concentration of essential oils used. The complete inhibition of A. flavus growth was observed at 1000 ppm concentrations of dill essential oil, lemon basil essential oil, coriander essential oil and onion essential oil. While dill essential oil and lemon basil essential oils showed marked inhibition of aflatoxin B1 produced by A. flavus at all concentrations tested (500, 750 and 1000 ppm).

Antimicrobial Activity of Honey and Propolis from Alba County, Romania.

Investigating the quality of bee products obtained across different geographical regions and analyzing their antimicrobial activity is of significant interest to various scientific disciplines. This study focuses on comparing the antimicrobial activity of honey and propolis samples from different areas of Alba County, Romania. The quality parameters of five samples of two types of bee products (honey and propolis) were assessed. Then, the samples were tested to comparatively determine their antimicrobial properties against 12 species of bacteria (Escherichia coli, Salmonella typhimurium, Salmonella enteritidis, Salmonella anatum, Salmonella choleraesuis, Pseudomonas aeruginosa, Pseudomonas fluorescens, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus, Bacillus subtilis, and Listeria monocytogenes) and 7 fungal strains (Candida albicans, Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum, Rhizopus stolonifer, Fusarium oxysporum, and Alternaria alternata). Of the bacterial strains, the most sensitive to the action of honey samples were the two strains of Staphylococcus followed by P. fluorescens. The two strains of Pseudomonas and L. monocytogenes were the most sensitive to the activity of propolis. Of the fungal strains, F. oxysporum was the most sensitive to the actions of both honey and propolis, followed by P. chrysogenum in the case of honey samples and the two Aspergillus strains in the case of propolis. These findings indicate that bee products are rich sources of bioactive compounds exhibiting strong antimicrobial properties and significant potential for the development of new phytopharmaceutical products.

Isolation and identification of endophytic fungi from Alhagi sparsifolia Shap. and their antibacterial activity

In order to explore the endophytic resources of Alhagi sparsifolia Shap. and identified novel antibacterial substances. Thirty endophytic fungal strains were isolated from the stems and roots of A. sparsifolia Shap. Morphological and molecular biology methods were used to identify ten strains of fungi, including four strains of Aspergillus niger, three strains of Alternaria alternata, two strains of Aspergillus flavus, and one strain of Fusarium incarnatum. All these strains were isolated from A. sparsifolia Shap. for the first time, and of these Aspergillus was the dominant genus. Antibacterial activity of the ten strains against Escherichia coli, Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa were evaluated using the disc diffusion method. The results demonstrated that the metabolites from all the strains had inhibitory effects on at least one indicator bacterium. Notably, the endophytic fungi AFJ3 and AFG6 demonstrated strong broad-spectrum antibacterial activity, particularly against E. coli, with inhibition zones measuring 32.0 ± 0.3 and 31.3 ± 0.3 mm, respectively. The three endophytic fungi (AFG1, AFG2, and AFG3) isolated from the roots demonstrated significant antibacterial activity against P. aeruginosa forming an inhibition zone of diameter 31.3 ± 0.1, 25.6 ± 0.2, and 25.6 ± 0.2 mm, respectively. However, the strains of endophytic fungi demonstrated no significant inhibitory effects on C. albicans. Ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry/mass spectrometry (UPLC-QTOF-MS/MS) analysis depicted that the ethyl acetate phase of AFJ3 and AFG6 fermentation broth predominantly contained organic acids, phenolic acids, flavonoids, and fatty acids. These secondary metabolites often exhibited good antibacterial activity. This study broadens our understanding of endophytic fungi in A. sparsifolia Shap. The antibacterial activity of some strains of endophytic fungi was significant, making it worthy of further research on their active material.

The role of Aspergillus flavus in modulating the physiological adjustments of sunflower to elevated CO2 and temperature

Exploring the interactions between plants and foliar endophytic fungi under varying climatic conditions is crucial for harnessing endophytes that enhance plant resilience to environmental stressors. This study examines the role of a specific strain of Aspergillus flavus as an endophyte in sunflowers under standard and altered CO2 and temperature regimes. We assessed the impact of this fungus on physiological traits such as chlorophyll and flavonoid content, gas exchange, and Chlorophyll a fluorescence using open-top chambers simulating ambient (∼420 µmol mol−1) and elevated (∼880 µmol mol−1) CO2 levels, along with a temperature increase of 3°C. The findings indicate that A. flavus promotes nitrogen assimilation and chlorophyll production under ambient conditions, potentially enhancing sunflower growth and photosynthetic performance. However, under elevated temperatures (eT), inoculation with A. flavus resulted in decreased biomass and reduced Photosystem II efficiency. Elevated CO2 (eCO2) conditions also led to unexpected negative effects, with reductions in foliar nitrogen, leaf area, and light capture efficiency, culminating in diminished biomass. When both elevated CO2 and temperature conditions were combined (eCO2eT), the interaction further impaired Photosystem II efficiency, suggesting exacerbated physiological stress. These results demonstrate that environmental modifications can transform A. flavus from a beneficial endophyte to a potential pathogen, highlighting the dual nature of plant-fungal interactions. This study underscores the complexity of these relationships under changing climatic conditions and suggests a cautious approach to the agricultural use of endophytes to ensure plant health and productivity.

Identification and Characterization of Multi-Mycotoxins Recovered from Dry Corn in Selected Markets in Enugu Metropolis, Enugu State, Nigeria

Corn is an important food crop that forms a major meal plan in Nigeria. Its high nutritious value also makes it perfect for fungi to thrive and produce its metabolites. Mycotoxin is a fungi metabolite that is toxic to both humans and animals. This study aimed at isolation of fungi from corn vended in selected markets in Enugu metropolis, identification and characterization of mycotoxin produced from the isolates. A total of 9 corn samples were collected from 3 different markets in Enugu metropolis comprising of Emene ,Ogbete and New markets respectively . The samples were cultured on potatoes dextrose agar for isolation, isolates were identified and characterized by cultural, biochemical and microscopic analysis of the organisms; selected isolates were further characterized by polymerase chain reaction (PCR). The isolates were subjected for mycotoxin production by culturing in potatoe dextrose broth for 14 days at 35°C after which the filtrates were assayed for the presence of mycotoxin using gas chromatography-mass spectroscopy (GC-MS) and individual aflatoxins were further characterized using high performance liquid chromatography (HPLC). From the study, Fusarium and Aspergillus flavus occurred at 66% respectively, Aspergillus niger at 55%, Mucor spp at 77%, Penicillium spp at 33%, and Aspergillus fumigates at 44%. PCR amplified products of the selected isolates showed positive amplification at 650bp for internal transcribed spacer gene. Mycotoxins identified from isolates were aflatotoxin, ochratoxin A (OTA), citrinin, patulin, citreoviridin, T-2 toxin, deoxynivalenol (DON), diacetoxyscirpenol, zearalenone (ZEN), nivalenol, Ht-2 toxin, cyclopiazonic acid with ochratoxin A, Diacetoxyscirpenol and Ht-2 toxin being above consumption limit at 2.64ug/kg,1.27ug/kg and 424.48ug/kg respectively. The isolates showed varied concentration of individual aflatoxins comprising of B1, B2, G1 and G2. These aflatoxins were produced by Aspergillus flavus strain ZMXL11, Aspergillus flavus strain AF-13, and Penicillium citrinin PEN-65 among, B1 was found to be above the maximum limit at 99% in all the isolates.Aflatoxin has been found as to be a group 1 carcinogen implicated in liver cancer. Constant consumption of mycotoxin contaminated corn could lead to varying health risk that includes liver cancer, kidney and gastrointestinal disturbances. This study showed that corn sold in selected markets in Enugu metropolis were contaminated with mycotoxigenic fungi that produced high levels of mycotoxin concentrations which is of public health concern.

Synthesis, Structural Elucidation, Density Functional Theory Calculations, In Vitro Antimicrobial, Anti‐Inflammatory and Anticancer Activities of Novel Zn (II)‐Group Fourteen Heterobimetallic Complexes Derived From Schiff Base Ligand

ABSTRACTIn the present work, new heterobimetallic complexes with the general formula [Zn(C16H32N8)M2(R)4Cl2], where M = Sn (IV) and Si (IV) and R = ‐CH3 and ‐C6H5, were synthesized by reacting the methanolic solution of the monometallic complex [Zn(C16H36N8)Cl2] with group 14 organometallic dichloride [(CH3)2SnCl2/(C6H5)2SnCl2/(CH3)2SiCl2/(C6H5)2SiCl2]. The structures of the synthesized complexes were determined using several spectrometric techniques, including FT‐IR, 1H NMR, 13C NMR, 119Sn NMR, 29Si NMR, ESI‐MS, PXRD, and molar conductivity measurements. Density functional theory (DFT) calculations were carried out to investigate the quantum chemical characteristics of the newly synthesized Zn (II) complexes. The antimicrobial potential of the monometallic and heterobimetallic complexes was evaluated against two Gram‐positive bacteria (Bacillus subtilis and Bacillus cereus), two Gram‐negative bacteria (Xanthomonas campestris and Pseudomonas aeruginosa), and two fungal strains (Aspergillus flavus and Fusarium oxysporum) by the agar well diffusion method, with heterobimetallic complex [Zn(C16H32N8)Sn2(C6H5)4Cl2] as the most potent complex against microbes. The complex [Zn(C16H32N8)Sn2(C6H5)4Cl2] exhibited significant potential in inhibiting inflammation, demonstrating an IC50 value of 9.75 μg/mL, which closely rivals that of the standard drug sodium diclofenac (IC50 = 4.59 μg/mL). Furthermore, all the synthesized compounds were assessed for their anticancer potential against three cancer cell lines (HCT‐116, MCF‐7, and HeLa) by the MTT assay. The results indicated that the complex [Zn(C16H32N8)Sn2(C6H5)4Cl2] exhibited the most pronounced cytotoxic effects, with values of 4.25 ± 0.15 μM, 4.90 ± 0.18 μM, and 5.20 ± 0.24 μM observed for HCT‐116, MCF‐7, and HeLa cancer cell lines, respectively.

Production of Single Cell Protein (SCP) from the Peel Waste of Pea, Potato, and Banana by Aspergillus Flavus NRRL 21882 as an Efficient Organic Poultry Supplement.

Food protein deficit has become a major issue worldwide, particularly in underdeveloped countries. Scientists are searching for a variety of less expensive solutions to this issue. One of these less expensive methods is to create single cell protein as a substrate from leftover fruit and vegetable waste, which is typically thrown away. In this regard, the fungal strain Aspergillus flavus (NRRL 21882) was used for the synthesis of SCP (single cell protein) from the waste of banana, potato, and pea. In this manner, 30 samples were collected from the whole substrate with a share of 10 samples each from banana, potato, and pea peels, which were in turn dried and powdered finely. The fermentation process was done by the process of solid state fermentation. Aspergillus flavus (NRRL 21882) generated the highest percentage, i.e. 60.67%, of crude protein from the pea peels. The composition of amino acids in crude proteins was also investigated. The findings demonstrated that the highest percentage of aspartic acid (13.34 ± 0.80%) and glutamic acid (14.92 ± 0.69%) was found in A. flavus single cell protein produced from pea peels. Soybean was supplemented with single cell protein in the boilers' diet. Compared to all treated groups, there was a substantial (p ≤ 0.05) increase in the level of antibody titer against the Newcastle disease vaccine. The supplementation of single cell protein with soybean meal had no effect on the levels of liver enzymes. The liver enzymes found in all four groups (A, B, C, and D) were within normal limits. None of the examined groups experienced any change in the feed conversion ratio, with all groups exhibiting an average FCR of 1.6. The current study concludes that broiler health and immunity is increased by supplementing poultry feed with single cell protein.

Protection capacity of Lactiplantibacillus plantarum 83114 against contamination of dry pet food with Aspergillus flavus

A wide range of pet food types are available on the market and one of the most common ingredients of dry food are cereals, vectors of harmful mycotoxins. Mycotoxins are toxic secondary fungal metabolites that contaminate dry pet food and their levels remain stable during food processing. This has a direct effect on the quality of the product and on animal health. Lactiplantibacillus plantarum 83114 is a probiotic strain isolated from traditional fermented milk with proven antifungal activity in different matrix. This study investigated the antifungal activities of this strain against contamination of dry pet food with a mycotoxigenic Aspergillus flavus strain. The antifungal activity was assessed using a complete culture of viable L. plantarum 83114, cell free supernatants (CFS), and non-viable cells (postbiotics). The CFS of L. plantarum CIDCA 83114 (pH 4.04) exhibited a high germination reduction rate (GR 94.7 %). However, the neutralized CFS (pH 7.0) lost approximately 60 % of its inhibitory capacity. L. plantarum CIDCA 83114 CFS and postbiotic treatments at 50 % exerted a total fungal growth inhibition, observed in a growth rate (KD) of zero. The viability of L. plantarum 83114 inoculated in dry pet food decreased by one logarithmic order after the first week of storage and, by the second week, no viable cells were detected. The DNA concentration of A. flavus in dry pet food supplemented with the probiotic strain remained consistently low and stable throughout the storage period. Lactiplantibacillus plantarum 83114 played a crucial role in inhibiting fungal growth and could act as a biopreservative agent in pet food.

Antituberculosis, antimicrobial, antioxidant, cytotoxicity and anti-inflammatory activity of Schiff base derived from 2,3-diaminophenazine moiety and its metal(II) complexes: structural elucidation, computational aspects, and biological evaluation

Abstract Enticed by the present scenario of infectious diseases, four new Co(II), Ni(II), Cu(II), and Cd(II) complexes of Schiff base ligand were synthesized from 6,6′-((1E-1′E)(phenazine-2,3-dielbis(azanylidene)-bis-(methanylidene)-bis-(3-(diethylamino)phenol)) (H 2 L) to ascertain as effective drug for antituberculosis, anti-inflammatory, antioxidant, cytotoxic and antimicrobial activities. The organic ligand and its metal(II) complexes were characterized by numerous physical and spectroscopic methods, which showed that the complexes have a general formula, [ML], (where M = Co(II) (C1), Ni(II) (C2), Cu(II) (C3) and Cd(II) (C4)), for metal complexes have been proposed and have a square planar geometry, are amorphous in nature, and are thermally stable. Data highlight obtained from activity testing against tuberculosis, inflammation, and oxidants that all compounds are significantly active against these symptoms. Also, was to evaluate the effectiveness of various compounds against bacterial and fungal strains. Specifically, four bacterial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) and two fungal strains (Aspergillus flavus and Candida albicans) were tested and compared to the results of some standard drugs. The results revealed that compound C4 was more effective against bacterial strains than the comparison standard drugs. In addition, C3 was found to be the most effective of the comparison antibiotics against fungi, while the other compounds showed moderate antifungal activity. Moreover, to support the vitro results, certain computational studies as molecular docking studies, DFT, MESP, and AMEDT were also conducted to confirm the effectiveness of an organic ligand and its complexes against tuberculosis. These studies revealed that C4 is the most effective against tuberculosis and has desirable effects such as absorption, no degradation and no hepatotoxicity, etc.

Antifungal Activity of Bhurjah (Betula Utilis d. Don) Bark in Human Pathogenic Fungi

Aim: To evaluate the antifungal activity of Bhurjah (Betula utilis D.Don) bark against six fungal strains. Water extract, alcohol extract of bark and essential oil (Birch oil) were screened against six fungal strain Trichophyton rubrum (7859), Epidermophyton floccosum (7880), Microsporum fulvum (7685), Aspergillus flavus (2590), Actinomucour elengi (963) and Candida albicans at four different concentrations (25µl, 50µl, 75µl, 100µl) using “Agar well diffusion method”. The MIC was tested using micro-PDA dilution method at concentrations ranging from (25µl, 50µl, 75µl, 100µl). Bhurjah essential oil showed significantly more inhibitory activity than fluconazole in case of 7880 (p value <0.05) and almost similar inhibitory activity as fluconazole in case of 7685 (p value >0.05). Bhurjah essential oil is shown to be effective against the growth of both M. fulvum with MIC value of 2.5% (v/v) and E. floccosum with MIC value of 2.5% (v/v) as determined by microbroth dilution. Bhurjah essential oil showed antifungal activity against two fungal strains E. floccosum (7880), M. fulvum (7685). Therefore Bhurjah essential oil can be used as antifungal agents for dermatophytosis causing strains i.e. E. floccosum (7880), M. fulvum (7685).

Effects of cold plasma on the growth and aflatoxin production of Aspergillus flavus

Cold plasma (CP) has an inactivating effect on bacteria, but little research has been done on fungi, especially on aflatoxin (AF)-producing strains of Aspergillus flavus (A. flavus). In this study, a CP device was utilized to investigate the destructive effects and mechanisms of different voltage treatments on AF-producing A. flavus strains. The inactivation curve was fitted using Weibull and Logistics kinetic models (R2 > 0.930). The results of viable spore count and AF detection showed that after 6 min of 60 V treatment, the total number of viable spores decreased by 4.47 log10 CFU/mL, and the AF level was found to be significantly lower after treatment (p < 0.05). The microstructure of A. flavus spores was severely damaged after DBDP treatment. The leakage of nucleic acids and proteins, lipid oxidation level, reactive oxygen level, and Fourier transform infrared spectroscopy analysis of spores all confirmed that the cell membrane of A. flavus was damaged after DBDP treatment. This study could provide reference methods for CP technology in the control of AF-producing A. flavus.

Elucidating Mycotoxin-Producing Aspergillus Species in River Water: An Advanced Molecular Diagnostic Study for the Assessment of Ecological Health and Contamination Risk

The primary goal of this research is to isolate mycotoxin-producing fungus from the Nagavali River. Examining isolated fungi involved analyzing their mycelium growth on culture media and detailed microscopic inspection. We employed PCR analysis utilizing universal primers ITS1 and ITS4 to accurately identify the species. Furthermore, we sequenced the amplified ITS region and rigorously analyzed the sequences using NCBI-BLASTn and the ITS2 database. The analysis found a high 96.38% genetic similarity to the Aspergillus flavus strain, resulting in a 600-base pair fragment size. The sequence was given the accession number OR536222 in the NCBI GenBank database. Phylogenetic analysis was performed to ascertain the particular strain of A. flavus and its source. Remarkably, this analysis led to the identification of a single new strain gene, which represents a novel discovery in the field of fungal research. These results underscore the vital significance of molecular techniques in promptly and precisely identifying organisms. This research enhances our understanding of mycotoxin contamination in water, providing valuable insights to improve detection and prevention strategies. It accentuates the overarching importance of conserving our water resources and upholding ecological equilibrium, ultimately safeguarding the well-being of both humanity and the environment.

Application of Cystoseira myrica phycosynthesized selenium nanoparticles incorporated with nano-chitosan to control aflatoxigenic fungi in fish feed.

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. 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. 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.

Molecular Identification of Ascomycetes from American Cranberry (Vaccinium macrocarpon Aiton) Grown in Plantation in Poland

The American cranberry is a perennial North American fruit plant that is grown successfully on commercial plantations in Poland. The purpose of this study was to recognize filamentous fungi that colonize roots, leaves, and fruits without visible disease symptoms. Pure fungal cultures were isolated from disinfected plant fragments in agar media and identified by sequencing common taxonomic DNA markers such as the ITS region, the TEF-1α, or RPB2 genes. Of the 141 isolates studied, 59% were identified as closely related to soil saprotrophs. They were classified primarily as showing the greatest similarity to type strains of Trichoderma amoenum, Trichoderma dorothopsis, Paraphaeosphaeria sporulosa, and Penicillium murcianum. Additionally, isolates that are most similar to strains of Penicillium crustosum, Aspergillus flavus, and Aspergillus versicolor that produced mycotoxins were detected. The fungi identified as closest to Alternaria geophila, Alternaria senecionicola, Paraphoma radicina, Pestalotiopsis unicolor, Pestalotiopsis scoparia, and Neopestalotiopsis spp., whose hosts are plants other than American cranberry, represented 33.81% of the isolates tested. Only 7.2% of the isolates corresponded to the species of Physalospora vaccinia, Diaporthe vaccinii, and Diaporthe eres, known cranberry pathogens. The results of this study can be used to identify latent plant infection and potential disease risks.

Divergent Aspergillus flavus corn population is composed of prolific conidium producers: Implications for saprophytic disease cycle

ABSTRACT The ascomycete fungus Aspergillus flavus infects and contaminates corn, peanuts, cottonseed, and tree nuts with toxic and carcinogenic aflatoxins. Subdivision between soil and host plant populations suggests that certain A. flavus strains are specialized to infect peanut, cotton, and corn despite having a broad host range. In this study, the ability of strains isolated from corn and/or soil in 11 Louisiana fields to produce conidia (field inoculum and male gamete) and sclerotia (resting bodies and female gamete) was assessed and compared with genotypic single-nucleotide polymorphism (SNP) differences between whole genomes. Corn strains produced upward of 47× more conidia than strains restricted to soil. Conversely, corn strains produced as much as 3000× fewer sclerotia than soil strains. Aspergillus flavus strains, typified by sclerotium diameter (small S-strains, <400 μm; large L-strains, >400 μm), belonged to separate clades. Several strains produced a mixture (M) of S and L sclerotia, and an intermediate number of conidia and sclerotia, compared with typical S-strains (minimal conidia, copious sclerotia) and L-strains (copious conidia, minimal sclerotia). They also belonged to a unique phylogenetic mixed (M) clade. Migration from soil to corn positively correlated with conidium production and negatively correlated with sclerotium production. Genetic differences correlated with differences in conidium and sclerotium production. Opposite skews in female (sclerotia) or male (conidia) gametic production by soil or corn strains, respectively, resulted in reduced effective breeding population sizes when comparing male:female gamete ratio with mating type distribution. Combining both soil and corn populations increased the effective breeding population, presumably due to contribution of male gametes from corn, which fertilize sclerotia on the soil surface. Incongruencies between aflatoxin clusters, strain morphotype designation, and whole genome phylogenies suggest a history of sexual reproduction within this Louisiana population, demonstrating the importance of conidium production, as infectious propagules and as fertilizers of the A. flavus soil population.

Extraction Kinetics and Antifungal Activities of Essential Oil from the Aerial Parts of Gros Baume (Hyptis suaveolens) Against Three Fungal Strains in Côte d'Ivoire

Introduction: Microscopic fungi colonize many food substrates resulting in considerable economic losses. Their development leads to an alteration in the organoleptic quality of the food, and produces mycotoxins. The aim of the present work was to evaluate the extraction kinetics and in vitro antifungal activity of the essential oil of Hyptis suaveolens on the growth of three toxigenic fungal strains. Methodology: The essential oil was extracted by steam distillation using a Clevenger-type device. It was tested for in vitro antifungal activity against three mold strains (Aspergillus flavus, Aspergillus niger and Fusarium sp) using the agar dilution method. Results: The results of the extraction kinetics evaluation show that in fifty minutes of distillation, almost all the essential oil contained in the aerial parts of H. suaveolens is recovered. In vitro antifungal tests showed a slight slowdown in mycelial growth for the three strains studied. However, the antifungal parameters determined show that these strains are sensitive to 50 μL/mL with a CMF of 100 μL/mL. This is just a simple fungistatic effect of this extract on the mycelial growth of the strains tested. Aspergillus strains seem to be slightly more affected than Fusarium strains. Conclusion: The antifungal potential of H. suaveolens essential oil does not offer a novel approach to the control of these three fungal strains.

Green synthesis of CuO nanoparticles using Ligustrum lucidum extract, and the antioxidant and antifungal evaluation

Biosynthesis of metal oxide nanoparticles using plant extract is an inexpensive, simple, rapid, and environmentally friendly approach to obtaining nanoparticles for biological applications. Herein, copper oxide nanoparticles (CuO-NPs) were successfully synthesized using an aqueous extract from Ligustrum lucidum leaves. The structural, optical, and morphological characteristics of the nanoparticles were assessed using x-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectrophotometer, transmission and scanning electron microscopy (TEM and SEM), and energy-dispersive x-ray (EDX). Nanocrystalline CuO with an average crystalline size of 22.0 nm and a band gap energy of 1.4 eV were confirmed from the XRD and UV-vis spectrophotometer, respectively. Morphological studies showed spherical nanoparticles, whose particle size estimation (30 ± 5 nm) agrees with the crystalline size deduced from the XRD pattern. A free radical scavenging activity of the CuO nanoparticles, evaluated using the 1, 1-diphenhyl-2-picrylhydrazyl (DPPH) assay, showed that it exhibited high antioxidant activity (IC50: 63.35 μg ml−1) that is concentration dependent. Antifungal evaluation using four different fungal strains (Aspergillus flavus, Aspergillus niger, Fusarium oxysporum, and Trichoderma harzianum) indicated a direct relationship between the potency of the particles and their concentration, with 1 ppm solution exhibiting the highest potency. The green synthesized CuO-NPs using Ligustrum lucidum may be potentially used as an antioxidant and antifungal agent for therapeutic applications.

Beta maritima mediated silver Nanoparticles: Characterization and evaluation of Antibacterial, Antifungal, and antioxidant activities

Silver nanoparticles (AgNPs) are known for their large surface area, which enhances their energy and antimicrobial activity. This study focused on producing silver nanoparticles using leaves from the Beta maritima (vulgaris) plant. Various techniques such as Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD) to characterize the synthesized AgNPs. The biologically synthesized AgNPs were then evaluated for their antimicrobial (antibacterial and antifungal) and antioxidant properties using different agents such as hydrogen peroxide (H2O2), 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2 azobis, 3-ethyl benzothiazoline-6-sulphonic acid (ABTS), and phosphomolybdate. The results showed that the AgNPs exhibited strong antifungal activity, particularly against fluconazole-resistant strains of Aspergillus niger and Aspergillus flavus, with a 61 % inhibition rate. Moreover, the AgNPs demonstrated significant antibacterial activity against various strains. At a concentration of 40 µg/mL, they exhibited 26 % inhibition against Staphylococcus aureus, 22 % against Micrococcus luteus, 18 % against E. coli, and 24 % against Klebsiella pneumonia, outperforming clarithromycin antibiotics. SEM analysis revealed spherical AgNPs, sized using nano measurer 1.2, EDX showed the presence of silver having composition at 80.38 %, and XRD confirmed a face-centered cubic crystalline structure. In addition to their characterization, the AgNPs also displayed strong antioxidant activity. At the same concentration, they showed percentages of 80.78 % (DPPH), 85.38 % (H2O2), 81.78 % (ABTS), and 80.66 % (phosphomolybdate), surpassing the antioxidant activity of the plant leaf extract alone. The synthesis of AgNPs using the extract of the Beta maritima (vulgaris) plant offers several advantages compared to other methods, including ease of handling, cost-effectiveness, wide availability, and eco-friendliness.

Mycoremediation of the novel fungicide ametoctradin by different agricultural soils and accelerated degradation utilizing selected fungal strains

Accelerating safety assessments for novel agrochemicals is imperative, advocating for in vitro setups to present pesticide biodegradation by soil microbiota before field studies. This approach enables metabolic profile generation in a controlled laboratory environment eliminating extrinsic factors. In the current study, ten different soil samples were utilized to check their capability to degrade Ametoctradin by their microbiota. Furthermore, five different fungal strains (Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Lasiodiplodia theobromae, and Penicillium chrysogenum) were utilized to degrade Ametoctradin in aqueous media. A degradation pathway was established using the metabolic patterns created during the biodegradation of Ametoctradin. In contrast to 47% degradation (T1/2 of 34 days) when Ametoctradin was left in the soil samples, the fungal strain Aspergillus fumigatus demonstrated 71% degradation of parent Ametoctradin with a half-life (T1/2) of 16 days. In conclusion, soil rich in microorganisms effectively cleans Ametoctradin-contaminated areas while Fungi have also been shown to be an effective, affordable, and promising way to remove Ametoctradin from the environment.