Antimicrobial Assessment of Zinc Oxide Nanoparticles Synthesized from Psidium guajava Stem Extract

Bio-synthesizing metal nanoparticles have gained global attention and interest because of their fast, non-toxic, cost-effective, one-step process, and environmentally friendly alternative. For its chemical, physical characteristics, nanoparticles have attracted a lot of interest in different areas, such as materials science and medicine, as well as electronics. The research is centered on the investigation of phytochemicals, and the subsequent characterization of these particles. The study also delves into the potential biological applications of zinc nanoparticles (ZnONPs). The Psidium guajava stem extract was utilized for ZnONPs synthesis. A comprehensive phytochemical analysis was performed on the extracted stem extract, revealing the presence of a diverse range of phytochemicals such as phenols, saponins, triterpenoids, steroids, tannin, catechin, and glycosides. The application of zinc ions to the bark extract resulted in the biosynthesis ZnONPs, which were then analyzed by UV-Vis spectral studies. The ZnONPs exhibited a surface plasmon resonance band at 368 nm and had a crystalline structure according to the X-ray diffraction spectrum. The scanning electron microscope revealed that the nanoparticles had a polydisperse distribution and a particle size ranging from 30 to 35 nm. The identification of the biomolecule group involved in the synthesis was made possible through the recording of the FTIR spectrum. The antibacterial activity of the ZnONPs was tested using the disc diffusion method against gram positive and negative bacteria. The results showed that the maximum zone of inhibition of ZnONP’s was 16±0.1 mm against P. aeruginosa and minimum zone of inhibition was against S. aureus 8±0.3 mm.