Investigation of Culture Conditions for Biosynthesis of Silver Nanoparticles using Aspergillus fumigatus

In this study، silver nanoparticles have been synthesized using Aspergillus fumigatus fungus. The effect of three independent variables including glucose content in culture media، initial pH and initial spore concentration on biosynthesis of silver nanoparticles has been investigated. These variables affect the cell morphology، cell mass، size and morphology of silver nanoparticles and reduction degree of silver ions. The formation of silver nanoparticles was confirmed spectrophotometerically. Size and morphology of silver nanoparticles were investigated using transmission electron microscopy (TEM). The effect of culture conditions on cell mass concentration as well as the effect of culture condition on the amount and size of synthesized silver nanoparticles was studied. As a result، the optimum culture condition for biosynthesis of silver nanoparticles was glucose concentration of 16 g/L، pH of 4. 5 and spore concentration of 1. 5×107 spore/L. TEM micrographs showed that the size of synthesized nanoparticles in optimized sample was in the range of 7- 19 nm.