Document Type : Original Article
national research centre
Spectroscopic department, physics division, National research centre
National research centre
This research focused on isolating and purifying the most frequent mycotoxin, aflatoxin-producing fungi from maize and soy-bean grains, which are of enormous economic worth as animal and human feed. Alpha and gamma aluminum oxide nanoparti-cles ( and γ-Al2O3 NPs) were also green generated from aluminum cans. XRD, HRTEM, and ATR-FTIR were utilized to analyze the structure and morphology of and γ-Al2O3 NPs. Also, studied the antifungal and insecticidal activity of aluminum nanoparticles produced, antifungal activities of both nanoparticles types were evaluated on the fungal isolates' growth at starting concentration of 0.67mg/ml using agar well diffusion method. The potential toxicity of and γ-Al2O3 NPs on Sitophilus oryzae and Oryzaephilus surinamensis adults was also evaluated at 50, 100, 150 and 200ppm. FESEM was used to examine the dead insects treated with 200 ppm of α or γ-AL2O3 NPs. Results confirmed the formation of and γ -Al2O3 NPs using ATR –FTIR and XRD. As measured by HRTEM, the particle size of and γ -Al2O3 NPs were found to be 4-8, 2-4nm, respectively. A wide variety of A. flavus, Fusarium sp, and Alternaria sp. fungi were found in the samples. Concerning, fungal isolates re-sponse, A. flavus was the most sensitive fungus against γ and -Al2O3 nanoparticles with inhibition zone 9 and 13.5mm, fol-lowed by F. oxysporum with 7 and 8mm for both types respectively. Alternaria sp. was the less sensitive fungal isolate with 1.5mm inhibition zone for both aluminum nanoparticles types. Thus, Alpha-Al2O3 nanoparticles possess a higher antifungal activity than γ-Al2O3 type. Results of insect toxicity showed that the survival and progeny production of both insect species were affected by the phase of nanoparticles, the applied concentration and exposure time. Gamma alumina NPs exhibited significant influence on both insect species more than alpha phase. Additionally, FESEM micrographs showed greater distribution intensity of γ-AL2O3 NPs on treated insects more than that of alpha phase. This study suggests that the synthesized alpha and gamma alumina NPs can provide eco-friendly insecticide and fungicidal to protect stored products.