Essential Oil of Nigella Sativa Based Synthesis of Silver Nanoparticles and Its Effect on Pathogenic Vibrio Harveyi and Vibrio Parahaemolyticus Isolated from Aquatic Environments

Green synthesized silver nanoparticles from Nigella sativa essential oil were used to study the inhibitory activity against pathogenic Vibrio harveyi and Vibrio parahaemolyticus isolated from aquatic environments. Essential oil of Nigella sativa based silver nanoparticle synthesis (EONs-AgNPs) was observed using UV-visible spectroscopy, FTIR and the morphological characteristics of the NPs were analyzed by scanning electron microscope (SEM). In the present study, increasing concentrations of EONs-AgNPs (30 μg/ml) effectively reduced the number of colonies of V. harveyi and V. parahaemolyticus. Among the two bacterial strains, EONs-AgNPs exhibited greater antibacterial activity against V. harveyi than V. parahaemolyticus. Similarly, the antibiofilm activity of EONs-AgNPs was also clearly observed under light and CLSM studies. EONs-AgNPs showed better inhibition of biofilm formation of V. harveyi followed by V. parahaemolyticus at 80 μg/ml after 24 h. The present study thus recommends that green synthesized silver nanoparticles of EONs-AgNPs could be used as an effective, safe and low cost control measures against pathogenic microbes of aquaculture importance.