Penicillum -Mediated Biosynthesis of Silver Nanoparti-cles and Its Antibacterial Activity

The aim of the study was to synthesize silver nanoparticles by using filamentous fungus Penicillium sp. The fungal culture was isolated from the soil samples collected from agriculture fields in Thiruvarur district, Tamil Nadu, India. The purified fungal isolates were inoculated in minimal medium and incubated at room temperature for three days. For the synthesis of silver nanoparticles, 50 ml of cell filtrate was mixed with equal volume of 1mM silver nitrate [AgNO3 (1 mM)] and agitated at room temperature in dark. The synthesis of silver nanoparticles was investigated by UV-Vis spectroscopy, Atomic force microscopy and Fourier Transform Infrared Spectroscopic analysis. Results indicate the synthesis of silver nanoparticles in the reaction mixture. Mechanism of silver nanoparticles synthesis was determined by nitrate reduction test

Characterization and optimization of bacterium isolated from soil samples for the production of siderophores

Siderophores are small molecules that can easily bind to ferric iron. As a chelating agent, they transport iron molecules inside the bacterial cell for various biochemical reactions. Due to its various applications in medicinal, industrial and environmental related aspects, this paper deals with characterization and optimization of few siderophores producing bacteria from the soil samples, collected from Chikkamagaluru district, Karnataka. The siderophores production was assayed qualitatively and quantitatively through Chrome Azurol S and the results showed positive for the strains VITVK5 and VITVK6 that grown in succinate medium. Further characterization and optimization results revealed that both the bacterium has the ability to yield siderophores (â¼60â80% units) in the optimum condition of pH 8, at 37â°C with glucose and sucrose as a carbon source and NaNO3 as a nitrogen source. Thus, the study concludes that strains VITVK5 and VITVK6 can be promising candidates for the siderophores production which can play major applications in medicinal and industrial aspects. Keywords: Siderophores, Chelation, Medicinal, Industrial, Optimizatio