Abstract
In this study, we evaluated the effect of silver nanoparticles were biosynthesis by Aspergillus terreus (KC462061) on growth and aflatoxin production by Five isolates of A. flavus were isolated from nuts. TEM micrographs observed that the particles of AgNP sarespherical in shape spherical or nearly sphericaland without significant agglomeration and the particle size ranges from 5 to 30 nm. Our results showed that all five A. flavus isolates were inhibited to various extents by different concentrations of silver nanoparticles but the best inhibition by 150 ppm with different significantly. In general, inhibition % of aflatoxin production at 50ppm ranged from 48.2 to 61.8%, at 100 ppm ranged from 46.1 to 82.2% whereas at 150ppm inhibition % reached to 100%. Scanning electron microscopy (SEM) was used to study antifungal activities of silver nanoparticles and to characterize the changes in morphology. SEM images indicate two different antifungal activities of AgNPs against A. flavus. AgNPs inhibited the growth of A. flavus by affecting cellular functions which caused deformation in fungal hyphae. In comparison, AgNPs cause reduce in spores number, malformation and hypertrophy, these effects lead to destroyed and damaged of spores. The aim of this work to study the possibility to use silver nanoparticles as an alternative to fungicides for controlling growth and aflatoxin production.