Plant-mediated green route to the synthesis of zinc oxide nanoparticles: in vitro antibacterial potential

The plant-mediated, sustainable, facile, eco-friendly, and simple green approaches for the fabrication of metal oxide nanoparticles (NPs) have recently attracted the ever-increasing attention of the scientific community. To date, there has not been any research on green synthesis of ZnO-NPs by Piper guineense (Uziza) seeds widely used as a therapeutic agent is the novelty of the current study. The bioaugmented ZnO-NPs have been manufactured by Uziza seed extract using zinc acetate dihydrate as the precursor and sodium hydroxide with calcination. The hexagonal/spherical crystalline structure at high purely with a mean size of 7.39 nm was confirmed via XRD and SEM analyses of ZnO-NPs. A strong absorption peak at about 350 nm, specific for ZnO-NPs, was observed by a UV-visible spectrometer. The optical bandgap of ZnO-NPs was estimated as about 3.58 eV by the Kubelka-Munk formula. FTIR findings indicated the presence of biofunctional groups responsible for the bioreduction of bulk zinc acetate to ZnO-NPs. The growth rates of E. coli (ATCC 25,922) significantly decreased with ZnO-NPs exhibited compared to the controls. This is making ZnO-NPs promising effective candidates for medical sectors and environmental applications. This current study is hoped to supply a better understanding of the phytosynthesis of ZnO-NPs and promote the advance of green approaches based on plants.