Dataset Information

Synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide.

ABSTRACT: The increasing challenge of antibiotic resistance requires not only the discovery of new antibiotics, but also the development of new alternative approaches. Herein, the synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide combination is reported. Unlike the bacteriostatic or slightly bactericidal activity achieved by using each agent alone, using these two agents in combination, even at relatively low concentrations, resulted in complete eradication of both the Gram negative Escherichia coli and the Gram positive Staphylococcus aureus in short treatment times indicating a clear synergistic effect between them. Modifying the surface chemistry of silver nanoparticles and the accompanied change in their surface charge enabled a further enhancement of such synergistic effect implying the importance of this aspect. Mechanistically, a Fenton-like reaction between silver nanoparticles and hydrogen peroxide is discussed and hypothesized to be the basis of the observed synergy. Achieving such a significant antibacterial activity at low concentrations reduces the potential toxicity of these agents and hence enables their utilization as an alternative antibacterial approach in wider range of applications.

SUBMITTER: Alkawareek MY

PROVIDER: S-EPMC6687290 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide.

Alkawareek Mahmoud Y MY Bahlool Ahmad A Abulateefeh Samer R SR Alkilany Alaaldin M AM

PloS one 20190808 8

The increasing challenge of antibiotic resistance requires not only the discovery of new antibiotics, but also the development of new alternative approaches. Herein, the synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide combination is reported. Unlike the bacteriostatic or slightly bactericidal activity achieved by using each agent alone, using these two agents in combination, even at relatively low concentrations, resulted in complete eradication of both the Gram ...[more]

PMID: 31393906

Similar Datasets

Project description:Silver nanoparticles plays a vital role in the development of new antimicrobial substances against a number of pathogenic microorganisms. These nanoparticles due to their smaller size could be very effective as they can improve the antibacterial activity through lysis of bacterial cell wall. Green synthesis of metal nanoparticles using various plants and plant products has recently been successfully accomplished. However, few studies have investigated the use of industrial waste materials in nanoparticle synthesis. In the present investigation, synthesis of silver nanoparticles (AgNPs) was attempted using the aqueous extract of corn leaf waste of Zea mays, which is a waste material from the corn industry. The synthesized AgNPs were evaluated for their antibacterial activity against foodborne pathogenic bacteria (Bacillus cereus ATCC 13061, Listeria monocytogenes ATCC 19115, Staphylococcus aureus ATCC 49444, Escherichia coli ATCC 43890, and Salmonella Typhimurium ATCC 43174) along with the study of its synergistic antibacterial activity. The anticandidal activity of AgNPs were evaluated against Candida species (C. albicans KACC 30003 and KACC 30062, C. glabrata KBNO6P00368, C. geochares KACC 30061, and C. saitoana KACC 41238), together with the antioxidant potential. The biosynthesized AgNPs were characterized by UV-Vis spectrophotometry with surface plasmon resonance at 450 nm followed by the analysis using scanning electron microscope, X-ray diffraction, Fourier-transform infrared spectroscopy and thermogravimetric analysis. The AgNPs displayed moderate antibacterial activity (9.26-11.57 mm inhibition zone) against all five foodborne pathogenic bacteria. When AgNPs were mixed with standard antibacterial or anticandidal agent, they displayed strong synergistic antibacterial (10.62-12.80 mm inhibition zones) and anticandidal activity (11.43-14.33 mm inhibition zones). In addition, the AgNPs exhibited strong antioxidant potential. The overall results highlighted the potential use of maize industrial waste materials in the synthesis of AgNPs and their utilization in various applications particularly as antibacterial substance in food packaging, food preservation to protect against various dreadful foodborne pathogenic bacteria together with its biomedical, pharmaceutical based activities.

Project description:BackgroundIt is generally accepted that antibacterial properties of Ag nanoparticles (AgNPs) are dictated by their dissolved fraction. However, dissolution-based concept alone does not fully explain the toxic potency of nanoparticulate silver compared to silver ions.Methodology/principal findingsHerein, we demonstrated that the direct contact between bacterial cell and AgNPs' surface enhanced the toxicity of nanosilver. More specifically, cell-NP contact increased the cellular uptake of particle-associated Ag ions - the single and ultimate cause of toxicity. To prove that, we evaluated the toxicity of three different AgNPs (uncoated, PVP-coated and protein-coated) to six bacterial strains: Gram-negative Escherichia coli, Pseudomonas fluorescens, P. putida and P. aeruginosa and Gram-positive Bacillus subtilis and Staphylococcus aureus. While the toxicity of AgNO3 to these bacteria varied only slightly (the 4-h EC50 ranged from 0.3 to 1.2 mg Ag/l), the 4-h EC50 values of protein-coated AgNPs for various bacterial strains differed remarkably, from 0.35 to 46 mg Ag/l. By systematically comparing the intracellular and extracellular free Ag(+) liberated from AgNPs, we demonstrated that not only extracellular dissolution in the bacterial test environment but also additional dissolution taking place at the particle-cell interface played an essential role in antibacterial action of AgNPs. The role of the NP-cell contact in dictating the antibacterial activity of Ag-NPs was additionally proven by the following observations: (i) separation of bacterial cells from AgNPs by particle-impermeable membrane (cut-off 20 kDa, ?4 nm) significantly reduced the toxicity of AgNPs and (ii) P. aeruginosa cells which tended to attach onto AgNPs, exhibited the highest sensitivity to all forms of nanoparticulate Ag.Conclusions/significanceOur findings provide new insights into the mode of antibacterial action of nanosilver and explain some discrepancies in this field, showing that "Ag-ion" and "particle-specific" mechanisms are not controversial but, rather, are two faces of the same coin.

Project description:BackgroundThere is worldwide interest in silver nanoparticles (AgNPs) synthesized by various chemical reactions for use in applications exploiting their antibacterial activity, even though these processes exhibit a broad range of toxicity in vertebrates and invertebrates alike. To avoid the chemical toxicity, biosynthesis (green synthesis) of metal nanoparticles is proposed as a cost-effective and environmental friendly alternative. Aloe vera leaf extract is a medicinal agent with multiple properties including an antibacterial effect. Moreover the constituents of aloe vera leaves include lignin, hemicellulose, and pectins which can be used in the reduction of silver ions to produce as AgNPs@aloe vera (AgNPs@AV) with antibacterial activity.MethodsAgNPs were prepared by an eco-friendly hydrothermal method using an aloe vera plant extract solution as both a reducing and stabilizing agent. AgNPs@AV were characterized using XRD and SEM. Additionally, an agar well diffusion method was used to screen for antimicrobial activity. MIC and MBC were used to correlate the concentration of AgNPs@AV its bactericidal effect. SEM was used to investigate bacterial inactivation. Then the toxicity with human cells was investigated using an MTT assay.ResultsThe synthesized AgNPs were crystalline with sizes of 70.70 ± 22-192.02 ± 53 nm as revealed using XRD and SEM. The sizes of AgNPs can be varied through alteration of times and temperatures used in their synthesis. These AgNPs were investigated for potential use as an antibacterial agent to inhibit pathogenic bacteria. Their antibacterial activity was tested on S. epidermidis and P. aeruginosa. The results showed that AgNPs had a high antibacterial which depended on their synthesis conditions, particularly when processed at 100 oC for 6 h and 200 oC for 12 h. The cytotoxicity of AgNPs was determined using human PBMCs revealing no obvious cytotoxicity. These results indicated that AgNPs@AV can be effectively utilized in pharmaceutical, biotechnological and biomedical applications.DiscussionAloe vera extract was processed using a green and facile method. This was a hydrothermal method to reduce silver nitrate to AgNPs@AV. Varying the hydrothermal temperature provided the fine spherical shaped nanoparticles. The size of the nanomaterial was affected by its thermal preparation. The particle size of AgNPs could be tuned by varying both time and temperature. A process using a pure AG phase could go to completion in 6 h at 200 oC, whereas reactions at lower temperatures required longer times. Moreover, the antibacterial effect of this hybrid nanomaterial was sufficient that it could be used to inhibit pathogenic bacteria since silver release was dependent upon its particle size. The high activity of the largest AgNPs might have resulted from a high concentration of aloe vera compounds incorporated into the AgNPs during hydrothermal synthesis.

Dataset Information

Synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide.

Publications

Synergistic antibacterial activity of silver nanoparticles and hydrogen peroxide.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets