Assessment of the effect of green synthesized silver nanoparticles against aquatic pathogen Aeromonas hydrophila using Artemia nauplii

Abstract

Fish disease is a major threat affecting the long-term development of aquaculture industry leading to great economic loss annually. <em>Aeromonas hydrophila</em> bacterium may be a primary or secondary cause of ulcers, hemorrhagic septicemia, fin rot and tail rot in fishes. Excess and abandoned usage of antibiotic substances caused a substantial growth of antibiotic resistant pathogens. Now a days, enduring research has focused on improvement of nanomaterials for efficient antimicrobial therapies. Comparing to the synthesis of other metallic nanoparticles, silver nanoparticles (AgNPs) has gained much attention because of its unique antimicrobial properties. The present study was aimed to green synthesize AgNPs using the <em>Annona squamosa</em> leaf extract which acts as a non-toxic reducing agent. The synthesized AgNPs were evaluated for biocompatibility and antagonistic efficacy against <em>A. hydrophila</em>. The green synthesized AgNPs were bio-physically characterized by UV-Visible spectroscopy, X-ray powder diffraction, High Resolution Transmission Electron Microscope, Fourier-transform infrared spectroscopy and Zeta Potential analysis. The particles were almost spherical shaped and in the range of 15-25 nm. Green synthesized AgNPs exhibited significant DPPH radical scavenging activity (64.62 %). Synthesis of AgNPs using widely available plants can be promoted as a potential eco-friendly option to chemical methods used for nanosynthesis. <em>In-vivo</em> studies confirmed that the AgNPs exhibited good antagonistic against <em>A. hydrophila </em>and also proved its non-toxic effect to <em>Artemia salina </em>nauplii.