%0 Journal Article
%T Biosynthesis of Gold Nanoparticles Using Fusarium oxysporum f. sp. cubense JT1, a Plant Pathogenic Fungus
%A Janki N. Thakker
%A Pranay Dalwadi
%A Pinakin C. Dhandhukia
%J ISRN Biotechnology
%D 2013
%R 10.5402/2013/515091
%X The development of reliable processes for the synthesis of gold nanoparticles is an important aspect of current nanotechnology research. Recently, reports are published on the extracellular as well as intracellular biosynthesis of gold nanoparticles using microorganisms. However, these methods of synthesis are rather slow. In present study, rapid and extracellular synthesis of gold nanoparticles using a plant pathogenic fungus F. oxysporum f. sp. cubense JT1 (FocJT1) is reported. Incubation of FocJT1 mycelium with auric chloride solution produces gold nanoparticles in 60£¿min. Gold nanoparticles were characterized by UV-Vis spectroscopy, FTIR, and particle size analysis. The particles synthesized were of 22£¿nm sized, capped by proteins, and posed antimicrobial activity against Pseudomonas sp. 1. Introduction Metal nanoparticles exhibit unique electronic, magnetic, catalytic, and optical properties that are different from bulk metals and dependent on their size and shape [1¨C5]. Gold is often considered the most inert of all metals; however, methods for preparing catalysts having nanoparticles of gold on oxide supports have opened up this new area of opportunity [6]. Gold nanoparticles are of interest mainly due to their stability under atmospheric conditions, resistance to oxidation, and biocompatibility [7, 8]. Therefore, development of techniques for synthesis of gold nanoparticles, of well-defined size and shape, is of great challenge. Different chemical methods developed to control the physical properties of the particles for their different applications. Most of these methods are still in the development stage, and problems are often experienced with stability of the nanoparticle preparations, control of the crystal growth, and aggregation of the particles [9, 10]. There is an increasing pressure to develop clean, nontoxic, and environmentally benign synthetic technologies. Microbial resistance against heavy metal ions has been exploited for biological metal recovery via reduction of the metal ions or formation of metal sulfides [7]. Recently, microorganisms such as bacteria and fungi were shown to be attractive alternative to synthesize gold nanoparticles [11, 12]. However, there is a limited amount of information on the extracellular biosynthesis of gold nanoparticles. Metal nanoparticle synthesis depends on the reducing agent, which reduces Au3+ in to Au0 state [12]. During plant-pathogen interaction, plants are known to produce reactive oxygen species as a defense mechanism against pathogens. For successful infection, pathogen must have high
%U http://www.hindawi.com/journals/isrn.biotechnology/2013/515091/