Biosynthesis of gold nanoparticles by the tropical marine yeast Yarrowia lipolytica NCIM 3589

The synthesis of gold nanoparticles by the non-conventional yeast Yarrowia lipolytica is described. Optical images. scanning electron microscopy (SEM) and energy dispersive spectrum analysis revealed the presence of gold crystals at pH 2.0. At pH 7.0 and pH 9.0. nanoparticles displayed a characteristic peak at 540 nm and their presence was confirmed by XRD studies. Both the yeast and filamentous forms synthesized nanoparticles under a variety of conditions. SEM and transmission electron microscopy (TEM) showed that nanoparticles were associated with the cell wall. This paper thus describes a novel application of the abundantly available biomass of Y. lipolytica. (C) 2009 Elsevier B.V. All rights reserved.