Biogenesis of nanoparticles with inhibitory effects on aflatoxin B1 production by Aspergillus flavus.

Background: Fungal nanofactories have been utilized to synthesize silver and gold nanoparticles. This study was designed to mycosynthesize and characterize silver and gold nanoparticles (AgNPs and AuNPs) and to study their effect on aflatoxin B1 production by Aspergillus flavus. Results: Silver and gold nanoparticles were synthesized by endophytic Aspergillus versicolor and then analyzed by UV–vis spectroscopy. The results revealed surface plasmon resonance peaks at 432 and 536 nm for Ag and Au nanoparticles, respectively. The obtained transmission electron microscopy results revealed the fashioning of spherical AgNPs and spherical and hexagonal AuNPs with a mean particle magnitude of 5–37 and 37–62 nm, respectively. X-ray diffraction showed the typical face-centered cubic structure of the mycosynthesized Ag and Au nanoparticles. An in vitro investigation showed that AgNPs, AuNPs, and their mixture at different concentrations (10000, 5000, 3000, 1000, 750, 500, 250, and 125 lg/mL) could inhibit or reduce the outgrowth and production of aflatoxin B1 (AFB1) by A. flavus. The concentration that showed no AFB1 production was less than those for the inhibition of fungal growth. AgNPs, AuNPs, and their mixture also exhibited promising antiradical scavenging activity. Conclusions: The use of fungi in the metallic nanoparticle’s fabrication and the utilization of mycosynthesized nanoparticles is promising as a substitute of chemicals to control antiaflatoxigenic fungi. [ABSTRACT FROM AUTHOR]