Elucidation of Biological Activity of Silver ‎Based Nanoparticles Using Plant ‎Constituents of Syzygium cumini

Abstract

<em> </em><em> We report the efficacy of the silver nanoparticles (AgNPs) synthesized using the leaf and bark extracts of Syzygium cumini (common name Jamun) with silver nitrate (AgNO₃)which were used as both reducing and capping agent at varied temperatures- 25°C, 37°C and 80°C. Three sets of AgNPs from leaf and bark extracts, were synthesized at the above mentioned temperatures, and then physical characterization using UV-Vis spectroscopy indicated a peak in the range of 385-460nm. The hydrodynamic radii measured by DLS clearly indicated the size of AgNPs in the range of 72-284nm. </em><br /> <em>The biological efficacy in terms of antimicrobial activity was assessed by Kirby Bauer method, applied for both Gram positive and Gram negative bacteria such as Staphylococcus aureus and Escherchia coli respectively. The Zone of inhibition (ZOI) diameter was found to be 22mm and 20mm in S.aureus and E.coli, indicated the bactericidal activity of AgNPs synthesized from leaf extract at 25°C was maximum. Further, the IC₅₀ of the same AgNP was 12.5µg/ml indicating 49.3% cytotoxicity in human breast adenocarcinoma cell line MCF-7 confirmed the anticancer activity, whereas in HEK cell line the cyototoxicity observed was only 8.95% at the same concentration. The upregulation of apoptotic marker “p53" post treatment with 12.5µg/ml for 24hrs as done by Western blotting. Hence, AgNPs synthesized by green synthesis are proposed as economical, environment friendly having immense potential for drug delivery.</em>