International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 8 (2013) pp. 155-168
Biosynthesis of silver nanoparticles from seaweed associated marine bacterium and its antimicrobial activity against UTI pathogens 
M.YokeshBabu*, V. JanakiDevi, C.M. Ramakritinan, R.Umarani2 , N.Nagarani1 and A.K.Kumaraguru 
1Department of Marine and Coastal Studies, Madurai Kamaraj University, Madurai-625021, Tamilnadu, India 2 Department of Zoology, Devangar Arts college, Arupukottai-626101, Tamilnadu, India *Corresponding author e-mail: 
The silver nanoparticles were synthesized using marine bacteria Bacillus sp. NJYRK was isolated from seaweed Padina gymnosphora. Preliminary formation of nanoparticles was confirmed with UV-vis spectrum at the absorbance of 420nm and it is characterized with XRD, FTIR, EDAX, AFM and TEM. The EDAX portraits the presence of silver, the AFM and TEM revealed the sizes of polydispersed (10-30nm) nanoparticles in the medium, the silver nano crystals formation (2 ) was exhibited by XRD spectrum, and FTIR analysis represented the biological compounds involved in nanoparticle synthesis. The antibacterial property of the silver nanoparticles was tested against UTI pathogens. The Antibiotic assay tests (Zone of inhibition, CFU assay and MIC test) reveals the concentration of more than 10 g/ml of silver nanoparticles were inhibited the growth of UTI pathogens. The present investigation states that the marine bacteria synthesized silver nanoparticles have potent antibacterial activity even in minimum concentration against UTI bacteria. 
Antibacterial activity; Bacillus sp. NJYRK; Seaweed; Silver nanoparticles; UTI pathogens.