Ocimum tenuiflorum leaf extract as a green mediator for the synthesis of ZnO nanocapsules inactivating bacterial pathogens

Abstract

ZnO nanoparticles, as fabricated using Ocimum tenuiflorum leaf extract, have been investigated for their photocatalytic and antimicrobial activities. However, the ZnO nanoparticles were synthesized using precursor, Zn(CH3COO)2·2H2O at different concentrations (5, 10 and 50 mmol kg−1) at 70 °C and pH 11.5. The synthesized materials were characterized by employing Fourier transform infrared spectroscopy, UV–Visible, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy techniques. As recorded from UV–Visible studies, there was a drastic decrease in the energy band gap value (Eg) from 3.63 to 3.20 eV with the concentration of precursor, Zn(CH3COO)2·2H2O. The synthesized materials were examined for their photocatalytic activity towards the degradation of methyl orange dye and also for antibacterial action against Bacillus subtilis, Staphylococcus aureus and Escherichia coli pathogenic bacteria.