Mycosynthesis of silver nanoparticles by Aspergillus flavus : characterization and antifungal activity

Abstract

The present study aimed to mycosynthesize silver nanoparticles (AgNPs) by Aspergillus flavus and to assess their antifungal activity. The presence of AgNPs was certified by colour change from yellow to brown and by the maximum absorbance at 420 nm, because of Surface Plasmon resonance. Transmission Electron Microscopy images revealed the aproximately spherical shape of AgNPs, dimensions ranging between 3.3 and 40 nm, crystalline structure and a good dispersion. AgNPs presented antifungal activity against Aspergillus ochraceus and Penicillium expansum but totally inhibited Fusarium oxysporum. Minimum inhibitory concentration (MIC) varied from 7.5 (Penicillium expansum and Fusarium oxysporum) to 12.5 μg/mL (Aspergillus ochraceus).