
In recent years, the role of metal nanoparticles in medicine and biology has rapidly increased, due to ease of synthesis, surface functionalization and biocompatible unique properties. In this paper, extracellular biosynthesis of Silver nanoparticles (AgNaPs) using methanol extract of Cauliflower leaves (Brassica oleracea L.) has been attempted and achieved rapid formation of AgNaPs in a short duration. The resulting AgNaPs were analyzed using UV-visible spectroscopy, Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy. The UV-visible spectrum showed a peak at 430nm corresponding to the Plasmon absorbance of the AgNaPs. FTIR spectra suggested the presence of biomolecules on the surface of the AgNaPs and XRD confirms the crystalline nature of the AgNaPs. The synthesized AgNaPs showed predominantly spherical structure and their sizes ranging from 20-70nm and 10-21nm under SEM and HRTEM observation respectively. The synthesized AgNaPs showed better antioxidant and efficiently inhibited various pathogenic organisms and reduced viability of the MDA-MB-231 and HeLa cells in a dose-dependent manner. This paper reported that the green chemistry approach for the synthesis of AgNaPs using methanol extract of cauliflower leaves would be a better alternative to the existing methods. The process may be helpful for the synthesis of plant based AgNaPs pharmaceutically useful drugs.