Green synthesis and physical properties of Gum Arabic‐silver nanoparticles and its antibacterial efficacy against fish bacterial pathogens
Mahmoud M. El‐Adawy, Alaa Eldin Eissa, Mohamed Shaalan, Ahmed A. Ahmed, Nehal A. Younis, Mona Ismail, Mohamed Abdelsalam
Abstract
This study aimed to assess the antibacterial efficacy of Gum Arabic-based silver nanoparticles against certain fish bacterial pathogens. Silver nanoparticles were green-synthesized using Gum Arabic (AgNPs-GA), which served as a stabilizing and reducing agent. The AgNPs-GA were analysed using a UV spectrophotometer set at a wavelength of 450 nm. Transmission electron micrograph analysis showed that nearly all AgNPs-GA were sphere-shaped and 10.0 nm in diameter. Dynamic light scattering (DLS) analysis showed a narrow size distribution curve, whose highest peak was at 26.2 nm. The particles were negatively charged (−17.1 ± 4.9 mV). Silver concentration measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and found to be 104 µg/ml. The in vitro antibacterial activity of AgNPs-GA was tested against Aeromonas hydrophila and Pseudomonas aeruginosa. Gum Arabic-silver nanoparticles exhibited clear inhibition zones of 22 and 20 mm against A. hydrophila and P. aeruginosa, with a minimum inhibitory concentration of 1.625 µg/ml and 3.25 µg/ml for AgNPs-GA respectively. The antibiofilm activity indicated that AgNPs-GA significantly inhibit A. hydrophila and P. aeruginosa biofilm formation at AgNPs-GA concentrations of 1.625 µg/ml. There was no significant difference at a AgNPs-GA concentration of 0.8215 µg/ml between the control-positive groups and the AgNPs-GA treatment groups in both bacterial strains. In summary, green-synthesized sliver nanoparticles display efficient antibacterial properties, which suggests that they would be suitable for use in a commercialized antibacterial product for the aquaculture industry.