Nano zinc oxide - An alternate zinc supplement for livestock.

Aim: This study was aimed to investigate antimicrobial and cytotoxicity effect of nano ZnO in in vitro for the application of livestock feed supplement. Materials and Methods: Nano ZnO was synthesized by wet chemical precipitation method using zinc acetate as a precursor and sodium hydroxide was used for reducing the precursor salt. The properties of synthesized powder were characterized using ultraviolet (UV)-visible spectroscopy, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. In vitro antimicrobial activities were analyzed against the pathogenic bacteria in poultry Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus aeruginosa. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was conducted to analyze the cytotoxicity effect of nano ZnO. Results: SEM showed a spherical ZnO particle in the range of 70-100 nm. The size of the particle and purity of the sample were confirmed by XRD. The nano-sized ZnO particles exhibited the UV absorption peak at 335 nm. In FTIR spectroscopy, pure ZnO nanoparticles showed stretching vibrations at 4000-5000 cm-1. ZnO nanoparticles exhibited remarkable antibacterial activity against E. coli, S. aureus, K. pneumoniae, and S. aeruginosa bacterial strains. Cell viability was significantly reduced in a dose-dependent manner in the cytotoxicity study. Conclusion: From the broad-spectrum antibacterial activity and the lower cytotoxicity observed at the prescribed dose, it is concluded that nano ZnO powder is a potential alternate zinc supplement for livestock. [ABSTRACT FROM AUTHOR]