Exploration on green synthesis of gold nanoparticles by a marine‐derived fungus <i>Aspergillus sydowii</i>

Abstract

Production of gold nanoparticles (GNPs) by biological route was examined using a marine‐derived fungal isolate. The isolated strain was identified as Aspergillus sydowii based on morphological traits and molecular identification technique. The test strain exhibited the potential to produce GNPs. A noteworthy observation was that mode of biosynthesis (extracellular/intracellular) depended on supplied gold ion concentration. As revealed by the color of the filtrate, at lower concentrations of gold ion larger size particles were obtained, while higher concentrations supported synthesis of smaller particles. The particles biosynthesized at 3 mM gold chloride were found to be spherical and nearly monodisperse in nature. The particles were found to be in the size range of 8.7–15.6 nm with a mean diameter of 10 nm. Based on the findings it can be concluded that marine‐derived fungus A. sydowii could be a promising candidate for synthesizing GNPs using green chemistry approach. Hence, the protocol is ecofriendly. The present study is the first ever report on biosynthesis of GNPs using a marine‐derived A. sydowii. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 194–197, 2015