Silver nanoparticles: A novel antibacterial agent for control of Cronobacter sakazakii

Abstract

Silver nanoparticles (AgNP) have been widely applied because of their broad spectrum of antimicrobial activities against bacteria, fungi, and viruses. However, little research has been done to evaluate their effects on Cronobacter sakazakii, an opportunistic pathogen usually infecting infants and having a high fatality rate. The aims of this work were to investigate the antibacterial property of novel, synthesized, positively charged silver nanoparticles against C. sakazakii and to discuss the potential antibacterial mechanisms involved. In this study, the spherical and face-centered cubic silver nanoparticles had a mean particle size of 31.2 nm and were synthesized by reducing Ag + using citrate and dispersed by glycerol and polyvinylpyrrolidone (PVP) under alkaline conditions. Minimum inhibitory concentrations (MIC) and inhibition zone tests showed that the AgNP exhibited strong antibacterial activity against 4 tested C. sakazakii strains with mean MIC of 62.5 to 125 mg/L and average inhibition zone diameters of 13.8 to 16.3 mm. Silver nanoparticles caused cell membrane injury accompanied by adsorption of AgNP onto the cell surface, as shown by changes in cell morphology, cell membrane hyperpolarization, and accelerated leakage of intracellular reducing sugars and proteins outward from the cytoplasm. In addition, dysfunction of the respiratory chain was induced after treatment with AgNP, which was supported by a decrease in intracellular ATP and inhibition of related dehydrogenases. This research indicates that AgNP could be a novel and efficient antibacterial agent to control C. sakazakii contamination in environments producing powdered infant formulas from milk.

Unveiling the potentials of biocompatible silver nanoparticles on human lung carcinoma A549 cells and Helicobacter pylori

“…Phytochemicals-medicated synthesis of metal nanoparticles has received due attention because of their bioactivities such as antibiotic, cytotoxic, drug cargo and photocatalytic potentials 1,2 . Among the metallic nanomaterials, silver nanoparticles (AgNPs) are of significance for their antibacterial effect on human pathogens 3–5 , wound healing 6 , antioxidant 7 , anticancer activities, and dental applications as acrylic resins, composite resins and adhesives, endodontics, periodontal materials, porcelain restoration, titanium implants, and orthodontics 8 . The surgical sutures, when coated with AgNPs are shown to prevent the post wound healing infections 9 .…”

Methods of Encapsulation of Biomacromolecules and Living Cells. Prospects of Using Metal–Organic Frameworks

“…Polyacrylamide gel is used quite often [103] despite its toxicity. Other carriers such as PVA-based cryogels [104,105], ENT/ENTP photocrosslinked polymers (polymer mixture based on polyethylene or polypropylene glycol, hydroxyethyl acrylate, and isophorone diisocyanate, which is polymerized under near UV irradiation) or modified PVA [106], granules and films based on polyvinyl chloride [107], hydrogels based on chitosan [108][109][110], polycarbamoyl sulfonate [111,112], and polyurethane [113,114], peptide polymers [115], biotin-avidin linkers [116][117][118], solgel matrices based on aluminum oxide [119] or composite polymers [120][121][122][123], as well as electropolymeriz able polyaniline films [124][125][126][127] and other compounds [128,129], and nanostructured materials (including carbon nanotubes and metal nanoparticles) [130][131][132][133][134][135][136][137] should also be noted. A common disadvantage of encapsulation in gels and polymers is diffusion restrictions imposed by the carrier nature, which in some cases appreciably reduce the rate of biocatalysis and the activity of biocomponents.…”

Creation of Biocidal Coatings using the Stabilization of Silver Nanoparticles in Aqueous Acrylic Dispersions

“…Colloidal solutions of metallic silver nanoparticles (AgNPs) are promising, as they can meet most of the requirements of the above-mentioned biocides with sufficient control of stabilization (selection and concentration of surfactants, degree of conversion) and environmental conditions (pH, viscosity, electrolytes) (Wang et al, 2018;Adur et al, 2018;Deshmukh et al, 2019).…”