title: Extracellular synthesis of silver nanoparticles by novel Pseudomonas veronii AS41G inhabiting Annona squamosa L. and their bactericidal activity.
abstract: In present investigation extracellular synthesis of silver nanoparticles were synthesized using cell free supernatant of Pseudomonas veronii AS41G isolated from Annona squamosa L. The bacterium significantly reduced silver nitrate to generate silver nanoparticles which was characterized with hyphenated techniques. Synthesis of silver nanoparticles preliminary confirmed by UV-Visible spectrophotometry with the intense peak at 410nm, Further FTIR analysis revealed the possible role of biomolecules in the supernatant responsible for mediating the nanoparticles formation. The XRD spectra exhibited the characteristic Bragg peaks of 100, 111, 200, and 220 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. TEM microgram showed polydispersity of nanoparticles with size ranging from 5 to 50nm. Synthesized silver nanoparticles showed antibacterial activity against human and environmental pathogens including MRSA. The study enlightens the role of biosynthesized silver nanoparticles as an emerging alternative for drug resistant microorganisms. The obtained results are promising enough to pave the environmentally benign nanoparticle synthesis processes without use of any toxic chemicals and also envision the emerging role of endophytes towards synthesis of nanoparticles. With scanty reports available on P.veronii species, a new role has been reported in this study which will be very valuable for future researchers working on it.
authors.affiliation: Herbal Drug Technological Laboratory, Department of Studies in Microbiology, University of Mysore, India.
authors.forename: Syed
authors.initials: S
authors.lastname: Baker
authors.affiliation: Trace Elements Speciation Research Laboratory, Environmental and Analytical Chemistry Division, School of Advanced Sciences, VIT University, Vellore, India.
authors.forename: K
authors.initials: K
authors.lastname: Mohan Kumar
authors.affiliation: Coffee Board Biotechnological Research, Mysore, India.
authors.forename: P
authors.initials: P
authors.lastname: Santosh
authors.affiliation: Herbal Drug Technological Laboratory, Department of Studies in Microbiology, University of Mysore, India.
authors.forename: D
authors.initials: D
authors.lastname: Rakshith
authors.affiliation: Herbal Drug Technological Laboratory, Department of Studies in Microbiology, University of Mysore, India. Electronic address: satish.micro@gmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Satish
mesh_terms: D031041:Annona / Q000378:metabolism / Q000382:microbiology*; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D060026:Endophytes / Q000378:metabolism*; D005110:Extracellular Space; D055772:Green Chemistry Technology; D053768:Metal Nanoparticles / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D011549:Pseudomonas / Q000378:metabolism*; D012834:Silver / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; C586932:colloidal silver; D012834:Silver
keywords: Annona squamosa L.; Endophyte; Pseudomonas veronii AS41G; Silver nanoparticles