Abstract:
Green nanoparticle synthesis techniques for various biological activities and medical
applications are desired because of their bio-compatibilit. Hence, in this study, silver
nanoparticles (AgNPs) were synthesized using root extracts (aqueous, methanol and hexane) of
V.officinalis. The antibacterial efficacy of the nanoparticles was assayed by the Kirby–Bauer
disc diffusion method against bacterial pathogens such as Escherichia coli and Staphylococcus
aureus. The minimum inhibitory concentration (MIC) of the synthesized AgNPs against the
microorganisms was also determined. The formation of the silver nanoparticles (AgNPs) was
visually observed by the colour change of the solution from milky white to deep brown. It was
also characterized with Surface Plasmon Resonance using ultraviolet-visible (UV) spectroscopy.
The crystal structure and functional groups were characterized by X-ray diffractometer (XRD)
and Fourier transform infrared (FT-IR) spectroscopy respectively. The synthesized AgNPs
exhibited good antibacterial activity against bacterial pathogens such as Escherichia coli and
Staphylococcus aureus. The AgNPs from the methanol extract of V.officinalis displayed the
lowest MIC (10.42 µg/ml) value against S. aureus. The results revealed that plant extracts
assisted the synthesis of AgNPs as stabilizing and reducing agents and strong antibacterial
activity against bacterial pathogens. Further works are required to investigate other biological
activities of green synthesized silver nanoparticles.