Noncytotoxic silver nanoparticles as a new antimicrobial strategy

Abstract

Drug-resistance of bacteria is an ongoing problem in hospital treatment. The main mechanism of bacterial virulency in human infections is based on their adhesion ability and biofilm formation. Many approaches have been invented to overcome this problem, i.e. treatment with antibacterial biomolecules, which have some limitations e.g. enzymatic degradation and short shelf stability. Silver nanoparticles (AgNPs) may be alternative to these strategies due to their unique and high antibacterial properties. Herein, we report on yeast Saccharomyces cerevisiae extracellular-based synthesis of AgNPs. Transmission electron microscopy (TEM) revealed the morphology and structure of the metallic nanoparticles, which showed a uniform distribution and good colloid stability, measured by hydrodynamic light scattering (DLS). The energy dispersive X-ray spectroscopy (EDS) of NPs confirms the presence of silver and showed that sulfur-rich compounds act as a capping agent being adsorbed on the surface of AgNPs. Antimicrobial tests showed that AgNPs inhibit the bacteria growth, while have no impact on fungi growth. Moreover, tested NPs was characterized by high inhibitory potential of bacteria biofilm formation but also eradication of established biofilms. The cytotoxic effect of the NPs on four mammalian normal and cancer cell lines was tested through the metabolic activity, cell viability and wound-healing assays. Last, but not least, ability to deep penetration of the silver colloid to the root canal was imaged by scanning electron microscopy (SEM) to show its potential as the material for root-end filling.

Effect of Biologically and Chemically Synthesized AgNPs on Multi-Drug Resistant (MDR) Dermatophyte Bacterial Isolates

“…They mentioned that the biosynthesized AgNPs were significantly more effective against S. aureus and P. aeruginosa than the chemically synthesized AgNPs using Polyvinylpyrrolidone (PVP) as a stabilizing agent. These results were also compatible with those reported by Skóra et al (2021) who investigated the antibacterial and antibiofilm activities of AgNPs against 18 medically important MDR bacteria including S. aureus and E. coli. They found that Acinetobacter baumannii and S. aureus strains, were the most affected.…”

Phytosynthesis of silver nanoparticles from Jatropha integerrima Jacq. flower extract and their possible applications as antibacterial and antioxidant agent

“…So, it is difficult to enter into gram-positive bacteria than gram-negative bacteria ( Erjaee et al, 2017 ). Earlier studies have shown that AgNPs were active against a wide range of pathogenic bacteria due to their effective antibacterial properties ( Gandhi et al, 2021 , Skóra et al, 2021 , Urnukhsaikhan et al, 2021 ).…”

“…But the role of AgNPs on human cells is unknown when their antibacterial capability is considered in the context of human use. For instance, silver nanoparticles were less toxic to eukaryotic cells, combined with their antibacterial capability, could be particularly valuable in endodontic treatment when bacteria in the root canal system must be eliminated ( Skóra et al, 2021 ). Silver NPs are also employed as antiseptic and disinfection agent because of their potential antibacterial property ( Das et al, 2019 ).…”

Nanoparticles of Bioactive Metals/Metal Oxides and Their Nanocomposites with Antibacterial Drugs for Biomedical Applications

“…Ag NPs also show antifungal activity against C. albicans , C. tropicalis [ 56 , 57 ], and Fusarium oxysporum f. sp. radicis-lycopersici [ 58 ].…”