Inhibition of the Vancomycin Resistance in Staphylococcus aureus in Egypt Using Silver Nanoparticles

Abstract

Staphylococcus aureus is a major human pathogen that is sometimes resistant to vancomycin. In this study, the prevalence of vancomycin-resistant Staphylococcus aureus (VRSA) was studied. 100 isolates of S. aureus were identified based on biochemical and molecular evidence. The antibiotic susceptibility of the studied isolates was tested against 13 antibiotics by the disc diffusion method that showed 24 vancomycin-resistant isolates. The minimum inhibitory concentrations (MICs) were estimated by the agar dilution method to determine vancomycin intermediate-resistant S. aureus (VISA) and VRSA. The resistance gene cluster (vanA, vanR, vanH, and vanY) was amplified by PCR and then sequenced. Amplification of vanA and vanR genes showed that they are present in 21.4% and 14.3% of VRSA isolates, respectively, whereas none of the studied genes has been detected in VISA strains. A significant antimicrobial effect toward VRSA isolates using silver nanoparticles (AgNPs) synthesized from S. aureus and rosemary leaves was recorded. This study confirmed the existence of VRSA strains in Egypt. Furthermore, the use of silver nanoparticles inhibits these vancomycin-resistant S. aureus strains in vitro.

Enhancement of the Protective Activity of Vanillic Acid against Tetrachloro-Carbon (CCl4) Hepatotoxicity in Male Rats by the Synthesis of Silver Nanoparticles (AgNPs)

“…The silver nitrate nanoparticles of vanillic acid were synthesized by the photo-mediated method for reducing silver ions as follows: two grams of vanillic acid was dissolved in 10 mL of ethanol and then completed by distilled water up to 100 mL; twenty milligrams of silver nitrate crystals (Sigma-Aldrich, St. Louis, MO, USA) was added to the vanillic acid solution and thoroughly mixed by a magnetic stirrer; the pH was adjusted by 1.0 M NaOH to 10.0. The color of the solution was initially whitish, then changed to yellow, and subsequently to dark brown ensuring the formation of the silver nanoparticle [ 30 , 35 ].…”

“…The samples were diluted ten times in deionized water before analysis and 250 μL of the suspension was transferred to a low-volume disposable cuvette. Prior to measuring, the sample was equilibrated at 20 °C for 2 min [ 30 , 38 ].…”

“…Applications of nanoparticle technology in the field of nanomedicine via nano-delivery systems has increased during the last decade where these nanoscale range materials are applied as diagnostic tools or delivery agents of therapeutic materials to the targeted sites under a precise scientific discipline [ 27 , 28 , 29 , 30 ]. Nanotechnology has helped in treating multiple chronic human diseases through the site-specific and target-oriented delivery of specific medicines [ 31 , 32 ].…”

“…The biomedical characteristics and uses of silver-based nanostructures were extensively characterized by Burdușel et al [ 33 ]. Silver nanoparticles succeeded in combating extensively drug-resistant Pseudomonas aeruginosa [ 34 ], and inhibiting vancomycin resistance in Staphylococcus aureus [ 30 ].…”

Recent advances in nanoantibiotics against multidrug-resistant bacteria

“…27 Nanomaterials (NMs) are advantageous as active antibacterial agents due to their exceedingly large surface area relative to their size. 28 NMs may provide high bioactivity at an extremely low concentration. 29 By adjusting the physicochemical properties of numerous materials, humans can generate various effective antimicrobials that can combat drug-resistant pathogens.…”