An evaluation of antifungal and antitoxigenicity effects of Ag/Zn and Ag nanoparticles on Aspergillus parasiticus growth and aflatoxin production

Background: Aspergillus parasiticus is one of the primary sources of aflatoxin contamination in agricultural crops, especially nuts. Aflatoxin contamination is one of the most challenging problems in the production and exportation of pistachios. Materials and Methods: In this study, the antifungal effects of the silver-zinc mixture and silver nanoparticles on the mycelia growth, spore germination and aflatoxin production of Aspergillus parasiticus have been evaluated. Results: The findings of the current study showed that the concentrations of 1250 ppm of Ag/Zn and 100-200 ppm of Ag nanoparticles inhibit mycelia growth and the spore germination of Aspergillus parasiticus in liquid and solid media significantly, but the concentration of 25 ppm of both nanoparticles has no inhibitory effects on the A. pararsiticus growth parameter. The results showed that the rate of inhibitory effects depends on the type of the medium and nanoparticles, but the fungal isolate had no significant effects on nanoparticles’ inhibitory features. Conclusions: Ag/Zn nanoparticles had no regular effect on the reduction of aflatoxin production, yet Ag nanoparticles reduced the production of aflatoxins, especially aflatoxins B2 and G2.