Biogenic synthesis of silver-nanoparticles with the brackish water cyanobacterium <i>Nostoc sphaeroides</i> and assessment of antibacterial activity against urinary tract infecting bacteria
Chita Ranjan Sahoo, Surendra Swain, Alexander Maniangat Luke, Sudhir Kumar Paidesetty, Rabindra N. Padhy
Abstract
The aim of this study was to isolate a filamentous nitrogen-fixing cyanobacterium Nostoc sphaeroides (NS) from brackish water of Chilika Lake, Odisha coast, and exploration of its use in the biosynthesis of silver-nanoparticles (AgNPs) against the urinary tract–infecting bacterial strains. The synthesized NS-AgNPs were structurally characterized by analytical techniques such as UV-visible-spectrophotometry, FTIR, XRD, SEM and SEM-EDX. The antibacterial efficacy of synthesized AgNPs had remarkable in vitro activities with the MIC value of 50 mg/ml. Moreover, Nostocine A, the inherent bioactive compound of Nostoc sp. was further investigated for molecular docking studies against the targeted bacterial DNA gyrase (Escherichia coli) and the obtained docking score was −7.9 kCal/mol as compared with the standard drug, Ciprofloxacin of a docking score −7.8 kCal/mol. The concordance between molecular docking and experimental results is excellent. Thus, the biogenic-synthesized “N. sphaeroides-AgNPs” would be used as an antibacterial agent in future.