Synthesis of silver nanoparticles using biotransformations by Saccharomyces boulardii

Abstract

Green synthesis of nanoparticles (NPs) using microorganisms is ecofriendly and gives researchers greater opportunities in sizes and shapes of the synthesized NPs. The aims of this research were the biosynthesis of silver NPs by biotransformations using Saccharomyces boulardii and analysis of the sizes and shapes of the produced NPs. Dried (commercially available) and freshly cultured S. boulardii were used as the biocatalyst. Dried yeast synthesized few NPs, but freshly cultured yeast produced a large amount of NPs. It was seen from transmission electron microscopy (TEM) micrographs that individual silver NPs as well as a number of aggregates with almost spherical shapes and sizes of about 8-26 nm were synthesized. It was shown that the NPs were mainly synthesized intracellularly, which might be due to the reductases inside the cells. Therefore, the biomass should be used in the synthesis, instead of discarding it. Previous researchers used only the supernatant and reported that the synthesis is extracellular.