Morphological, optical and antibacterial study of green synthesized silver nanoparticles via Vernonia amygdalina

Green synthesis of silver nanoparticles (AgNPs) through a fresh leave of Vernonia amygdalina (FLVA) inherent in flavonoids, tannins and phenols phytochemical as a capping and reducing agent is demonstrated in this work. The antibacterial activities of the formulated AgNPs were studied. The synthesized AgNPs were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray dispersive spectroscopy (XRD), UV-Visible spectroscopy and Fourier transform infrared spectroscopy (FT-IR) analysis. The UV-visible confirm the formation of AgNPs with surface plasmon resonance (SPR) absorbance peak between 430 and 465 nm. The TEM analysis gave a spherical morphology with particle size ranged between 2 and 10 nm. The XRD gave a face-centered cubic phase with the crystalline structure of AgNPs. To our knowledge, the antibacterial activities of AgNPs have been studied in details but the green synthesis of AgNPs via FLVA against Coliform and Staphylococcus aureus bacterial strains has not been reported in the literature. It is noteworthy that the formulated AgNPs show effective susceptibility to the AgNPs against the bacterial strains compared with Gentamicin. Hence, the obtained AgNPs via facile and innocuous synthesis, demonstrated good therapeutic agent against human pathogens strains due to its non-toxicity and facile method of synthesis. (C) 2019 Elsevier Ltd. All rights reserved.