Biosynthesis of TiO and ZnO nanoparticles by IBRC-M 10214 in different conditions of medium.

In the recent years, green synthesis is a novel method without some disadvantages of physical and chemical methods. In this approach, bacteria, archaebacteria, fungi, and plants may be applied without utilizing toxic and expensive materials for metal nanoparticles (MNPs) preparation. In this study, we used Taguchi method to obtain optimum conditions in titanium dioxide and zinc oxide nanoparticle (NPs) biosynthesis by IBRC-M 10214. Design and analysis of Taguchi experiments (an orthogonal assay and analysis of variance [ANOVA]) carried out by the Qualitek-4 software. Effects of TiO(OH), incubation temperature, and culturing time for synthesis of TiO NPs as well as ZnCl concentration, glucose concentration, and incubation temperature for the preparation of ZnO NPs were evaluated as the controllable factors with 3 levels. Characterization of TiO and ZnO NPs were determined by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and dynamic light scattering (DLS) analysis. Also, the antimicrobial properties of these NPs were investigated based on agar diffusion assay of NPs dispersed in batch cultures using ATCC 25922 and ATCC 43300 as multidrug-resistant (MDR) bacteria. It was evaluated that TiO and ZnO NPs had respectively average diameter sizes of 104.63±27.75 and 18.11±8.93 nm with spherical shapes. In contrast to the TiO NPs without antibacterial activity, the ZnO NPs had antibacterial effects at 0.1 and 0.01 M of (ZnCl). The ZnO NPs have the antibacterial effect that can be operative in the medicinal aspect for fighting against prominent MDR bacteria such as ATCC 25922 and ATCC 43300. In total, this study presents a simple method in the biosynthesis of TiO2 and ZnO NPs with low the expense, eco-friendly, and high productivity properties.