Phytoextracts-Synthesized Silver Nanoparticles Inhibit Bacterial Fish Pathogen Aeromonas hydrophila

Abstract

Fish disease is a major stumbling block towards sustainable growth of the fisheries sector. Aeromonas hydrophila, which is a major infectious aquatic pathogen is reportedly the causative agent of ulcers, fin-rot, tail-rot, hemorrhagic septicemia in fish, and has reportedly developed resistance against many of the available antibiotics. In this context, the inhibitory function of silver nanoparticles (AgNPs) against A. hydrophila was studied to evaluate its possible application in aquaculture as alternative to antibiotics. AgNPs were synthesized using the leaf extracts of subtropical plants Mangifera indica (Mango), Eucalyptus terticornis (Eucalyptus), Carica papaya (Papaya) and Musa paradisiaca (Banana). The absorbance maxima, size range and shape of the AgNPs as characterized by the UV-Vis spectroscopy, high resolution transmission electron microscopy (HR-TEM), and energy dispersive X-ray spectroscopy (EDX) were, Mangifera-442, 50-65 nm, ovular; Eucalyptus-465, 60-150 nm, oval; Carica-442, 25-40 nm, round, irregular; and Musa-454, 10-50 nm, round, irregular, respectively. Well-diffusion of these AgNPs for their antimicrobial characteristics exhibited that, the papaya leaf extract synthesized AgNPs had maximum antimicrobial activity at 153.6 μg/ml concentrations, and that from the eucalyptus leaves was least effective. As observed, the potency of the nanoparticles enhanced with the decrease in particle size, from 60-150 nm in eucalyptus to 25-40 nm in papaya. Due to its purely natural sourcing, phytosynthesized AgNPs can be applied as alternative to antibiotics and other biocides as a cost-effective and eco-friendly therapeutic agent against A. hydrophila stimulated diseases in aquatic animals.

Antibacterial Activity of Green Synthesized Silver Nanoparticles Using Vasaka (Justicia adhatoda L.) Leaf Extract

“…Figures also show that there is variation in particle size, the estimated average particle size is 20 nm in the range is from 5 to 50 nm. The size of these biosynthesized Ag nanoparticles is conformity with the size of earlier reported biosynthesized Ag nanoparticles using the leaf extract of Mangifera indica (50-65 nm), Eucalyptus tereticornis (60-150 nm), Carica papaya (25-40 nm), Musa paradisiaca (10-50 nm) [5]. In the present study, the potentiality of silver nanoparticles as a common antimicrobial substance has been evaluated against P. aeruginosa MTCC 741 by standard methods.…”

“…The MIC value indicates that the green synthesized silver nanoparticles using the leaf extract of vasaka can inhibit the growth of P. aeruginosa MTCC 741 strain at the concentration of 10 -5 (M). This study is tuned with earlier reported studies: anti bacterial activity of Ag nanoparticles on fish pathogen and other microbes [3][4][5].…”

“…It is revealed that bacteria within biofilm are responsible for more than 80 % infectious diseases as well as more resistance to antibiotics [1]. In recent years, due to unique physical and chemical properties of nanoparticles, its uses to disrupt biofilm of bacteria are revolutionary steps in antimicrobial research [2][3][4][5][6][7][8][9][10][11][12][13]. The uses of silver and silver compounds are very well known from ancient time in case of dental work, catheters and burn wounds etc.…”

“…The uses of silver and silver compounds are very well known from ancient time in case of dental work, catheters and burn wounds etc. Thus, among the various inorganic metal nanoparticles, silver (Ag) nanoparticles have received substantial attention in the field of biological system, living organisms and medicine [3][4][5][7][8][9][10][11][12][13]. To use in biological field the metal nanoparticles should be biocompatible and free from toxic chemicals which are used to synthesis nanoparticles in traditional chemical process.…”

Antimicrobial Activities of Silver Nanoparticles Synthesized by Using Water Extract of Arnicae anthodium

“…Velmurugan et al [13] obtained AgNPs synthesized using the natural cashew nut shell liquid against bacterial fish pathogens. Mahanty et al [14] used phyto extracts-synthesized silver nanoparticles as cost-effective and ecofriendly therapeutic agents against Aeromonas hydrophila-stimulated diseases in aquatic animals.…”