Abstract
Flower-shaped zinc oxide (ZnO) nanostructures were prepared via a simple aqueous precipitation strategy at room temperature. The as-grown nanostructures were characterized by UV–vis spectroscopy, UV–vis diffuse reflectance spectroscopy (DRS), spectrofluorometry, Fourier transform infrared (FTIR) spectroscopy with attenuated total reflection (ATR), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The antifungal and anti-aflatoxigenic activities of the ZnO nanostructures were further investigated using a highly toxigenic strain of Aspergillus flavus Link under in vitro and in situ conditions. The results showed that the A. flavus isolate was inhibited to various extents by different concentrations of ZnO nanostructures, but the best inhibitions occurred at 1.25, 2.5, and 5 mM in the culture media. At these concentrations, suppression of aflatoxin biosynthesis (99.7%) was also observed. Moreover, a reasonable reduction in the aflatoxin content (69%) was observed in maize grains treated with the lowest ZnO concentration that exhibited the strongest inhibitory activity in the liquid media. SEM micrographs clearly indicate multiple degenerative alterations in fungal morphology after treatment with ZnO such as damage of the tubular filaments, loss of hyphae shape, as well as hyphae rupture. These results suggest that flower-shaped ZnO nanostructures exhibit strong antifungal and anti-aflatoxigenic activity with potential applications in the agro-food system.
Highlights
Transition metal-based oxides are among the most produced nanomaterials due to their multipurpose applications in chemistry, biology, medicine, biotechnology, molecular engineering, and physics
The results indicate that zinc oxide (ZnO) at 100 μg/g of maize was almost effective under the experimental conditions tested
The application of ZnO nanostructures recommended as an effective fungicide against the major fungal pathogen of maize
Summary
Transition metal-based oxides are among the most produced nanomaterials due to their multipurpose applications in chemistry, biology, medicine, biotechnology, molecular engineering, and physics. Dimensional nanostructured materials have attracted special attention; for that reason, considerable effort has been made to develop controlled synthesis protocols, since the properties and potential applications depend on their shape and size [1]. Zinc oxide (ZnO) is an Materials 2018, 11, 1265; doi:10.3390/ma11081265 www.mdpi.com/journal/materials. Being an n-type semiconductor, the electron mobility in ZnO nanomaterials is enhanced [4]. ZnO (21 CFR 182.8991) is considered as a GRAS (generally recognize as a safe) substance by the United States Food and Drug Administration. With the development of material science, it is expected that ZnO has further applications in many aspects of food and agriculture
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
