Abstract

SCREENING, ISOLATION, IDENTIFICATION, CHARACTERISATION AND APPLICATIONS OF SILVER NANOPARTICLES SYNTHESIZED FROM MARINE ACTINOMYCETES (STREPTOMYCES GRIESEORUBENS)

N. Vidhyashree* and Dr. S. Yamini Sudha Lakshmi

Abstract

Crystalline Silver Nano particles have been found to have diagnostic and therapeutic applications in medical field. In this study, the silver nanoparticles were synthesized biologically using silver as reducing agent. The extract was used from marine Actinomycetes for the study of screening, identification, characterization, antimicrobial, free radical scavenging and anti-cancer activities. Screening was done for antimicrobial activity. With 16SrRNA sequencing, the organism was identified as Streptomyces grieseorubens. The formation of silver nanoparticles were indicated by the colour change from colourless to reddish brown, characterized by SEM, TEM revealing the size of nanoparticle to be 50nm having hexagon shape. XRD and FTIR showing the crystalline nature and the functional groups (OH, C-C, NH) present in the nanoparticle. The antimicrobial study was made against B.subtilis, E.coli, S.aureus, and Proteus vulgaris. S.aureus, showed the maximum zone of inhibition around 15mm. These nanoparticles were found to have a significant free radical scavenging activity and a potent cytotoxic activity against MCF7 cell line invitro.

Keywords: Cytotoxic, Antibacterial, Free radical and Nanoparticles.