In the present investigation we report a green chemistry approach for the biological synthesis of silver nanoparticles using the seed extract of Foeniculum vulgare Mill (sompu). The synthesized nanoparticles were structurally characterized by UV-VIS spectrophotometer and XRD. Elemental and vibrational analyses were carried out using FTIR spectrophotometer and EDS, respectively. Reduction of silver ions using seed extract of Foeniculum vulgare resulted in the synthesis of nanoparticles. The seed extract showed an absorption peak at 475 nm in UV-VIS spectrum corresponding to the plasmon resonance of silver nanoparticles. FTIR spectrum showed the involvement of amides and amines in capping and reduction of silver nanoparticles. Antibacterial activity was screened using synthesized silver nanoparticles against Pseudomonas aeruginosa, Proteus mirabilis, Escherichia coli, Klebsiella pneumoniae and Shigella flexineri. Remarkable zone of inhibition was observed in the synthesized silver nanoparticles placed in the disc when compared to control disc (plant extract). Green synthesis of silver nanoparticles is a simple, cheap and environmentally benign alternative to physical and chemical procedures.

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Available from: Dr. M. THIYAGARAJAN, Oct 04, 2015
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