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

In this study, silver nanoparticles were synthesized  using the fungus, Aspergillus fumigatus. The effects of three independent variables including glucose content of culture media, initial pH and initial spore concentration on biosynthesis of silver nanoparticles were investigated. These variables affect cell morphology, cell mass, size and morphology of silver nanoparticles and degree of silver ion reduction. The formation of silver nanoparticles was confirmed spectrophotomterically. Size and morphology of silver nanoparticles were investigated using transmission electron microscopy (TEM). The effects of culture conditions on cell mass concentration as well as the amount and size of synthesized silver nanoparticles were studied. As a result, the optimum culture condition for biosynthesis of silver nanoparticles consisted of a 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 nanoparticles in the sample synthesized under optimized condition was in the range of 7-19 nm.