Abstract

ISOLATION, SCREENING, IDENTIFICATION, CHARACTERIZATION AND APPLICATIONS OF GREEN SYNTHESIZED SILVER NANOPARTICLE FROM MARINE ACTINOMYCETES-STREPTOMYCES ALTHIOTICUS

Dr.S.Yamini Sudha Lakhsmi*, Haritha Lakhsmi.D and Sharmila.S

Abstract

Crystalline Silver Nanoparticles have been found to have diagnostic and therapeutic applications in medical field. In the present study, the marine actinomycetes were isolated from the soil sample collected from the coastal area and the isolates were screened for antibacterial activity against the pathogenic bacteria by cross streaking method. The potential isolate was selected and it was identified as Streptomyces althioticus by 16SrRNA sequence method. The silver nanoparticles were synthesized from the potent isolate Streptomyces althioticus using silver nitrate as a reducing agent by biological method. 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 sphere shape. XRD and FTIR showing the crystalline nature and the functional groups (OH, C- C, NH) present in the nanoparticle. The antimicrobial study was carried out against B.subtilis, E.coli, S.aureus, and Proteus vulgaris. The maximum zone of inhibition was showed against B.subtilis around 21mm. These nanoparticles were found to have a significant free radical scavenging activity and a potent cytotoxic activity against MCF7 cell line invitro.

Keywords: Streptomyces althioticus, SEM, TEM, XRD, FTIR analysis, antimicrobial, free radical, cytotoxic activities.