TiO₂ Nanoparticles from Baker's Yeast: A Potent Antimicrobial

Titanium dioxide (TiO₂) has wide applications in food, cosmetics, pharmaceuticals and manufacturing due to its many properties such as photocatalytic activity and stability. In this study, the biosynthesis of TiO₂ nanoparticles (NPs) was achieved by using Baker's yeast. TiO₂ NPs were characterized by X-ray Diffraction (XRD), UV-Visible spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray analysis (EDX) studies. The XRD pattern confirmed the formation of pure anatase TiO₂ NPs. According to EDX data Ti, O, P and N were the key elements present in the sample. SEM and TEM revealed that the nanoparticles produced were spherical in shape with an average size of 6.7 ± 2.2 nm. The photocatalytic activity of TiO₂ NPs was studied by monitoring the degradation of methylene blue dye when treated with TiO₂ NPs. TiO₂ NPs were found to be highly photocatalytic comparable to commercially available 21 nm TiO₂ NPs. This study is the first report on antimicrobial study of yeast-mediated TiO₂ NPs synthesized using TiCl₃. Antimicrobial activity of TiO₂ NPs was greater against selected Gram-positive bacteria and Candida albicans when compared to Gram-negative bacteria both in the presence or absence of sunlight exposure. TiO₂ NPs expressed a significant effect on microbial growth. The results indicate the significant physical properties and the impact of yeast-mediated TiO₂ NPs as a novel antimicrobial.