Bioleaching of sand by the fungus fusarium oxysporum as a means of producing extracellular silica nanoparticles

The fungus Fusarium oxysporum was used in the bioleaching of silica nanoparticles from sand grains. The formation of silica nanoparticles was proceeded in a two-step process, first, leaching out silica from the sand grains in the form of silicic acid by proteins present in the fungul biomass, and then hydrolyzing the silicate complex by other specific proteins in the fungus to silica. The silica was in the form of nanoparticles capped by stabilizing proteins from 2 to 5 nm in size and was released into the solution by the fungus. It was found that the synthesis of oxide nanomaterials using microorganisms starting from potential waste material could lead to eco-friendly and economically viable methods for the large scale synthesis of nanomaterials.