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Senna, a medicinal herb, is highly susceptible to aflatoxin contamination, which often limits the export value of the final products due to the regulatory limits of importing countries. Presence of aflatoxin B1 (AFB1) was investigated in 229 senna pod samples at various stages from field to storage over three years. Higher incidence of AFB1 was revealed during the late harvest stage with a mean level of 52.4 µg/kg and a range of LOD-206 µg/kg. Out of 48 late harvest samples, 37 exceeded the AFFB1 limit of 2 µg/kg. In contrast, the majority of preharvest samples showed lower levels of AFB1 (1.0 µg/kg). During drying, increase in the mean AFB1 level to 4 µg/kg was observed and it could further increase to 18.1 μg/kg in storage. These results highlight the status of aflatoxin contamination in senna pods and emphasise the importance of implementing good agricultural practices in senna cultivation to mitigate AFB1 contamination. [ABSTRACT FROM AUTHOR]

In the present study, the composition of the essential oil and antimicrobial activity from aerial parts of Artemisia annua growing wild in north of Iran was investigated. The major ingredients of the essential oil of A. annua were camphor (29.2%), 1.8-cineole (13.3%), tetradecanol (6.16%), β-selinene (5.82%) and pinocarvone (3.86%). In the current study, the antimicrobial activity of A. annua was tested against 4 fish pathogenic bacteria including: Streptococcus iniae, Yersinia ruckeri, Aeromonas hydrophila and Lactococcus garvieae and 3 fish pathogenic fungi namely Saprolegnia sp., Fusarium solani and Aspergillus flavus. Based on the results, Y. ruckeri, A. hydrophila and Saprolegnia sp. showed higher sensitivity to the essential oil of A. annua L. than to control antibiotic (ciprofloxacin, 0.3% w/v). Maximum antibacterial and antifungal activity was observed against Y. ruckeri (22.6±0.6 mm) and Saprolegnia sp. (18.7±0.8 mm) respectively, while S. iniae (10.2±1.2 mm) and A. flavus (12.9±0.82 mm) showed the least sensitivity. In addition, the minimum inhibitory concentration (MIC) test showed that concentrations of the essential oil within the range between 3.2 to 25 μg/L were able to inhibit the growth of the selected bacterial and fungal pathogens. According to the results, that the essential oil of A. annua could be a potential new and more effective antibacterial component for the aquaculture industry. [ABSTRACT FROM AUTHOR]

The biogenic synthesis of nanoparticles is a sustainable, environmentally friendly, and cost-effective approach that offer significant advantages over conventional methods. In this study, phosphorous nanoparticles (P-NPs) were synthesized biogenically using Serendipita indica and evaluated for their antifungal potential against Aspergillus tubingensis and Aspergillus flavus. The synthesized P-NPs were characterized using multiple techniques including UV–Vis spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), and Scanning and Transmission electron microscopy (SEM and TEM). UV–Vis spectra revealed a characteristic absorption peak at 359 nm, while zeta potential analysis recorded a value of −0.11 mV. XRD analysis identified distinct structural peaks and SEM and TEM confirmed rod-shaped nanoparticles with sizes ranging from 70 to 88 nm. The antifungal efficacy was assessed using a two-fold serial dilution method, revealing dose-dependent effects. Lower P-NPs concentrations caused conidial malformations, whereas higher concentrations resulted in significant loss of fungal viability. SEM analysis further demonstrated severe morphological damage to fungal hyphae, including ruptured cell membranes, and reduced spore counts. These findings suggest that biogenically synthesized P-NPs are highly effective against Aspergillus spp. and represent a promising eco-friendly alternative to conventional fungicides for sustainable fungal management. [ABSTRACT FROM AUTHOR]

Pistachios, often referred to as "green gold" due to their high economic value, are vulnerable to various pests, with aflatoxin contamination being a particularly critical issue. The cracks in pistachio shells create an ideal environment for fungal growth and the insects that spread them. Contamination by toxic molds and subsequent aflatoxin production poses a significant threat to pistachio exports, making accurate detection essential. Current detection methods primarily rely on chemical analysis, which can be time-consuming, labor-intensive, and expensive. In this study, we developed a cost-effective and reliable approach for detecting fungal contamination in pistachios by combining an electronic nose (E-nose) equipped with eight metal oxide semiconductor sensors and color imaging technology. Experimental treatments were prepared using three spore concentrations: 102, 104, and 106 spores/mL. A medium-level data fusion strategy was employed and compared with Linear Discriminant Analysis (LDA) and Support Vector Machine (SVM) models. Results showed that different fungal concentrations could be effectively distinguished by the third day post-inoculation. These findings demonstrate that integrating color imaging with E-nose technology offers a powerful solution for intelligent, in situ detection of fungal contamination, ensuring food safety and quality control in the pistachio industry. [ABSTRACT FROM AUTHOR]

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AbstractOver the years, L-asparaginase’s therapeutic properties have been well documented. L- asparaginase is a chemotherapeutic agent that is also used in the food processing industry. The L-asparaginase enzyme from Aspergillus flavus was isolated and characterized in the present study. The fungus was identified using morphological observations and ITS (Internal Transcribed Spacer) sequencing techniques. The molecular weight of the isolated L-asparaginase enzyme was determined using SDS gel electrophoresis and it was found around 78 kDa. The apparent Km and Vmax of pure L-asparaginase were 0.061 mM and 67.98 U/mL, respectively. The optimal pH condition and temperature for the purified L-asparaginase were 7.0 and 37 °C, respectively. The purified L-asparaginase enzyme had been inhibited by heavy metals like lead and mercury. In contrast to zinc, copper, and iron, which considerably reduced enzyme activity, magnesium, and manganese, had no impact on enzyme activity. Furthermore, the IC50 of the L-asparaginase enzyme in the WST-8 assay was 2.5 U/mL for the THP-1 Human monocytic leukemia cell line. As a consequence, the results showed that the pure L-asparaginase enzyme could possess qualities that could be employed in the treatment of cancer cells. [ABSTRACT FROM AUTHOR]

Essential oils of basil herbs such as nyazbo or sweet basil (Ocimum basilicum), holy basil or tulsi (O. tenuiflorum), and African or clove basil (O. gratissimum) have traditionally been used for their therapeutic potential. These medicinal herbs are being cultivated and consumed globally, and the increasing demand for antimicrobial and antifungal natural products has led to the assessment of the potential of essential oils of medicinal plants to inhibit mycelial growth rather than synthetic fungicides. Thus, the present study explored natural alternatives to inhibit mycelial growth (Aspergilus flavus) and aflatoxin production. Linalool (25.40%), methyl chavicol (37.63%), and eugenol (39.52%) were identified as chief compounds in the EOs of O. basilicum, O. tenuiflorum, and O. gratissimum respectively. Ocimum tenuiflorum EO demonstrated the highest inhibitory activity at 0.75 µL mL− 1 against Aspergillus flavus and totally inhibited the synthesis of aflatoxin B1 (AFB1). The AFB2 production was completely inhibited at 0.25 µL mL− 1 by O. tenuiflorum EO, while O. basilicum and O. gratissimum EOs showed inhibition against AFB2 at 0.50 µL mL− 1, and 1.0 µL mL− 1, respectively. The present study suggests that EOs of basil herbs could be a potential natural alternative of synthetic fungicides to inhibit the fungal growth and aflatoxin production. [ABSTRACT FROM AUTHOR]

Introduction: This study investigated the antioxidant, antimicrobial, and insecticidal properties of Chamaemelum nobile (L.) essential oil (CN-EO), harvested in Taounate, Morocco. The molecular composition and chemical profile of CN-EO were also characterized. Methods: The CN-EO was extracted using a Clevenger apparatus. Its chemical composition was analyzed using gas chromatography-mass spectrometry (GC-MS). Antioxidant activity was evaluated using the DPPH assay, while antimicrobial properties were assessed via the disk diffusion method to measure inhibition zones against various bacterial and fungal strains. Insecticidal activity was tested through bioassays to determine insect mortality and repellency rates. Phylogenetic analysis of DNA sequences was conducted to confirm the species identity. Results: GC-MS analysis identified 24 compounds in CN-EO, with β-Oplopenone (18.66%), Spathulenol (14.90%), and Himachalene (12.47%) as major constituents. CN-EO exhibited strong antioxidant activity (IC50 = 135.8 ± 1.03 μg/mL). Antimicrobial assays revealed inhibition zones of up to 20.67 ± 0.58 mm (Staphylococcus aureus) and antifungal inhibition of 40.42% ± 2.82% against Aspergillus flavus. Insecticidal tests showed total insect mortality at 166 µL/L within 48 h and a 60% repellent effect. Phylogenetic analysis of the DNA sequence revealed a 99.22% similarity with Chamaemelum nobile (L.). Conclusion: These results demonstrate the significant potential of Moroccan CN-EO in phytomedicine. It exhibits a wide range of biological activities and shows great promise as a natural antioxidant, antimicrobial agent, antifungal, and insecticide. [ABSTRACT FROM AUTHOR]

Tobacco mildew is a common fungal disease that reduces tobacco quality, resulting in serious economic losses in the tobacco industry. In this study, the pathogens Aspergillus niger, Aspergillus flavus, and Rhizopus arrhizus were isolated from infected leaves. Furthermore, five plant endophytic bacteria isolated from healthy tobacco leaves were found to possess strong antifungal activity against these pathogens. Among these strains, Bacillus amyloliquefaciens ZH-2 exerted the strongest antagonistic effect against all mildew types (bacteriosphere diameter > 22 mm). The antagonistic action of ZH-2 was further observed using scanning electron microscopy, which revealed signs of contraction, deformation, and dissolution of the treated mycelia compared with that seen in the control group. The ZH-2 strain was found to produce high levels of proteases, chitinases, and β-1,3-glucanase, contributing to its antifungal activity via fungal cell wall rupture. The antifungal activity of ZH-2 was also demonstrated in the application test, as indicated by the significant reduction in mildew disease severity in tobacco leaves treated with this strain. Fermentation tests showed that the quality of ZH-2–treated, solid-state fermented tobacco leaves was superior to that of the control. Specifically, the alkaloid content significantly decreased by 10.62%, whereas the total and reduced sugar contents increased by 12.9 and 55.75%, respectively. Furthermore, macromolecular starch, cellulose, and protein contents significantly decreased by 25.85, 12.77, and 10.04%, respectively. These results indicate that the Bacillus amyloliquefaciens ZH-2 strain is effective against tobacco mildew and can improve tobacco quality upon solid-state fermentation. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the effects of selenium nanoparticles (SeNPs) and/or vitamin E (VE) on the growth, body composition, metabolic parameters, histopathology, and resistance of Nile tilapia to Aspergillus flavus. Results: Monosex Nile tilapia fingerlings were sourced from the Bazina farm and hatchery in Ismailia Governorate, Egypt, where the experiment was also conducted. The fish were acclimatized for 15 days before the trial. A total of 240 fingerlings (average weight 46 ± 3.0 g/fish) were divided equally across 12 concrete tanks (1 × 1 × 1.2 m, 1 m³ capacity), with 20 fish per tank. The fish were fed a control diet (T0), which was a basal diet with no supplementation, or one of three experimental diets for 60 days: T1 (1 mg SeNPs/kg), T2 (100 mg VE/kg), and T3 (1 mg SeNPs + 100 mg VE/kg). The experiment followed a completely randomized design (CRD) with three replicates per treatment. The combination of SeNPs and VE (T3) resulted in the best feed conversion ratio. A slight but significant increase (P < 0.05) in whole-body composition was observed in all treatment groups compared to the control. Biochemical parameters, serum digestive enzyme activity, and antioxidant levels improved significantly with dietary supplementation. Histopathological analysis revealed somewhat lacerated gill arches in fish fed SeNPs, VE, or their combination, but the overall gill structure remained normal. The SeNPs + VE group exhibited improved villi length and normal morphology of portal veins and hepatic sinusoids, though some vacuolated hepatocytes were noted. Fish in the SeNPs + VE group had the lowest mortality rates and the highest resistance to A. flavus. Conclusion: Supplementing diets with SeNPs and/or VE enhances growth, body composition, biochemical parameters, and histopathology in Nile tilapia. The combination of 1 mg SeNPs + 100 mg VE/kg improves immune response and growth, offering a promising strategy to enhance Tilapia health and productivity. [ABSTRACT FROM AUTHOR]

Introduction: Aspergillus flavus is an opportunistic pathogenic fungus that infects oilseed crops worldwide. When colonizing plants, it produces mycotoxins, including carcinogenic compounds such as aflatoxins. Mycotoxin contamination results in an important economic and health impact. The design of new strategies to control A. flavus colonization and mycotoxin contamination is paramount. Methods: The biocontrol potential of a promising new isolate of Pseudomonas spp., 20EI1 against A. flavus was assessed using bioassays and microscopy. To further elucidate the nature of this bacterial-fungal interaction, we also performed chemical and transcriptomics analyses. Results: In the present study, Pseudomonas spp., 20EI1 was able to reduce the growth of A. flavus. Furthermore, we determined that this growth inhibition is iron-dependent. In addition, Pseudomonas 20EI1 reduced or blocked the production of aflatoxin, as well as cyclopiazonic acid and kojic acid. Expression of iron-related genes was altered in the presence of the bacteria and genes involved in the production of aflatoxin were down-regulated. Iron supplementation partially reestablished their expression. Expression of other secondary metabolite (SM) genes was also reduced by the bacteria, including genes of clusters involved in cyclopiazonic acid, kojic acid and imizoquin biosynthesis, while genes of the cluster corresponding to aspergillicin, a siderophore, were upregulated. Interestingly, the global SM regulatory gene mtfA was significantly upregulated by 20EI1, which could have contributed to the observed alterations in SM. Discussion: Our results suggest that Pseudomonas 20EI1 is a promising biocontrol against A. flavus , and provide further insight into this iron-dependent bacterial-fungal interaction affecting the expression of numerous genes, among them those involved in SM. [ABSTRACT FROM AUTHOR]

In the present investigation, the bio-reduction of silver nitrate has been done using the extracts obtained from the leaves and flowers of Catharanthus roseus and the resultant silver nano particles were incorporated with ZnO through sonication. The ZnO was prepared via a simple soft chemical route. The characteristics of the resultant nanoparticles were analyzed using X-ray diffraction spectrometer, scanning electron microscope, Fourier Transform Infrared spectrophotometer, EDAX and elemental mapping techniques. The diffraction patterns of thus prepared ZnO nanomaterials revealed that they are crystallized with (101) plane which is the preferential orientation. The FTIR, report reveals that the phenolic compounds had played a vital role in the reduction of synthesized Ag nanoparticles. The SEM analysis revealed the coral rock like structure of the synthesized nanomaterials. The EDAX and mapping analysis confirms the presence of the elements Zn, Ag and O and C in the prepared samples. From the results, it can be concluded that the Catharanthus roseus leaves and flowers are good sources for the synthesis of silver nanoparticles. The plant mediated Ag incorporated ZnO showed better antibacterial property on Gram negative bacteria (Staphylococcus aureus and Escherichia coli) and Gram-positive bacteria (Klebsiella pneumonia).The antifungal action of Catharanthus roseus leaf and flower mediated Ag:ZnO nanoparticles were tested against three fungal strains namely Aspergillus Niger, Aspergillus flavus and Penicillium chrysogenum. Ag:ZnO:Leaf nanoparticles showed stronger antimicrobial activities when compared to the Ag:ZnO and Ag:ZnO:Flower nanoparticles. The radical scavenging activity named DPPH, was used to study antioxidant capability of the resultant nanoparticles and the related inhibition percentage of Ag:ZnO:Leaf and Ag:ZnO:Flower nanoparticles were found to be 65, 76 and 93%, respectively. [ABSTRACT FROM AUTHOR]