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Screening of silver nanoparticles producing cyanobacteria and its characterization
Authors: Pawar Sunil*, Bhosale Amarsinh, Mulani Parvin, Patekar Panchratna and Shaha Swarali.
Number of views: 606
Biosynthesis of nanoparticles is the major division in the field of applicable nanoscience and nanotechnology. Nanoparticles can be synthesized using plant extracts, enzymes, bacteria, fungi and algae. Nanoparticles can be made of materials of diverse chemical nature, the most common being metals, metal oxides, silicates, non-oxide ceramics, polymers, organics, carbon and biomolecules. Silver nanoparticles are widely used particularly in textiles, plastics and medical industries, changing the pattern of silver emission as these technologies and products diffuse through the global economy. In the present investigation, twenty cyanobacterial isolates were screened for the synthesis of silver nanoparticles. Out of that Oscillatoria spp. was shown to be capable to biosynthesize Ag-NPs. Silver nano particles synthesis of has been shown from filamentous Oscillatoria sp. and it was confirmed using yellowish-brown color in aqueous solution along with the uv-vis spectroscopy. It was confirmed by scanning electron microscopy (SEM) which showed that Ag-NPs were present and evenly distributed throughout the cell free liquid culture of the AgNO3incubated culture. XRD X-ray diffraction (XRD) was carried out to confirm crystalline nature of the particles and it is concluded that the mix phase of AgNO3 and silver nanoparticles is observed. FTIR was used to identify the biomolecules in Oscillatoria sp. responsible for the silver ions reduction and stabilization of reduced silver ions. The antibacterial activity of silver nanoparticles produced by Oscillatoria sp. was observed against pathogens, viz., E. coli, Klebsiella sp., Salmonella sp., Pseudomonas sp. using disc diffusion method. The bioactive-ty of the synthesized silver nanoparticles had inhibitory effect on important human pathogens. It would be desirable to develop a technology in which the specific size and shape of the particles could be obtained by the use of a specific strain of cyanobacteria.