Antimicrobial Effect Of Silver Nanoparticles Research Articles

The antimicrobial effects of silver nanoparticles obtained through the royal jelly on the yeasts Candida guilliermondii NP-4

The effect of silver nanoparticles (Ag NPs) obtained in the presence of royal jelly (RJ) on the growth of yeast Candida guilliermondii NP-4, on the total and H+-ATPase activity, as well as lipid peroxidation process and antioxidant enzymes (superoxide dismutase (SOD), catalase) activity was studied. It has been shown that RJ-mediated Ag NPs have a fungicide and fungistatic effects at the concentrations of 5.4 µg mL−1 and 27 µg mL−1, respectively. Under the influence of RJ-mediated Ag NPs, a decrease in total and H+-ATPase activity in yeast homogenates by ~ 90% and ~ 80% was observed, respectively. In yeast mitochondria total and H+-ATPase activity depression was detected by ~ 80% and ~ 90%, respectively. The amount of malondialdehyde in the Ag NPs exposed yeast homogenate increased ~ 60%, the catalase activity increased ~ 70%, and the SOD activity—~ 30%. The obtained data indicate that the use of RJ-mediated Ag NPs have a diverse range of influence on yeast cells. This approach may be important in the field of biomedical research aimed at evaluating the development of oxidative stress in cells. It may also contribute to a more comprehensive understanding of antimicrobial properties of RJ-mediated Ag NPs and help control the proliferation of pathogenic fungi.

Antibacterial efficacy of silver nanoparticles, sodium hypochlorite, chlorhexidine, and hypochlorous acid on dentinal surfaces infected with Enterococcus faecalis.

The purpose of this study was to evaluate the antibacterial effect of silver nanoparticles (AgNPs) against Enterococcus faecalis and compare it with different irrigation solutions. This study was performed using 64 dentin blocks. E. faecalis suspension was dispensed to each sample and incubated under anaerobic conditions at 37°C throughout 21 days. After the inoculation period, the following solutions were added to each group and kept for 5 min: Group 1, 5.25% sodium hypochlorite (NaOCl); Group 2, 2.5% NaOCl; Group 3, 1% NaOCl; Group 4, 2% chlorhexidine (CHX); Group 5, 200 ppm hypochlorous acid (HOCl); and Group 6, AgNPs. The samples of positive control were treated with sterile saline. Biofilm viability assay was performed using the LIVE/DEAD BacLight Bacterial Viability Kit. Samples were examined using confocal laser scanning microscopy, respectively. There was no significant difference between the 5.25% NaOCl, 2.5% NaOCl, and 1%NaOCl groups (p > .05). However, these groups showed statistically higher antibacterial activity than the 2% CHX, 200 ppm HOCl, and AgNP groups. Also, 2% CHX showed greater percentage of dead cells compared with the AgNP and HOCl groups. While AgNPs group showed lower dead cell rate than all NaOCl groups and 2% CHX, it caused higher dead cells than 200 ppm HOCl group. The 200 ppm HOCl group showed the lowest percentage of dead cells (p < .05) Although the antibacterial effect of AgNPs is not as high as NaOCl and CHX, it has considerable bactericidal activity against E. faecalis and can be improved by further studies. RESEARCH HIGHLIGHTS: New antimicrobial approaches for root canal irrigation. Antimicrobial effect of silver nanoparticles against E. faecalis. Elimination of the biofilm layer for the success of endodontic treatment.

Extended-spectrum β-lactamase-producing E. coli from retail meat and workers: genetic diversity, virulotyping, pathotyping and the antimicrobial effect of silver nanoparticles

BackgroundThe spread of extended-spectrum β-lactamases (ESBL) producing E. coli from food animals and the environment to humans has become a significant public health concern. The objectives of this study were to determine the occurrence, pathotypes, virulotypes, genotypes, and antimicrobial resistance patterns of ESBL-producing E. coli in retail meat samples and workers in retail meat shops in Egypt and to evaluate the bactericidal efficacy of silver nanoparticles (AgNPs-H2O2) against multidrug resistant (MDR) ESBL-producing E. coli.ResultsA total of 250 retail meat samples and 100 human worker samples (hand swabs and stool) were examined for the presence of ESBL- producing E. coli. Duck meat and workers’ hand swabs were the highest proportion of ESBL- producing E. coli isolates (81.1%), followed by camel meat (61.5%). Pathotyping revealed that the isolates belonged to groups A and B1. Virulotyping showed that the most prevalent virulence gene was Shiga toxin 2 (stx2) associated gene (36.9%), while none of the isolates harbored stx1 gene. Genotyping of the identified isolates from human and meat sources by REP-PCR showed 100% similarity within the same cluster between human and meat isolates. All isolates were classified as MDR with an average multiple antibiotic resistance (MAR) index of 0.7. AgNPs-H2O2 at concentrations of 0.625, 1.25, 2.5 and 5 μg/mL showed complete bacterial growth inhibition.ConclusionsVirulent MDR ESBL-producing E. coli were identified in retail meat products in Egypt, posing significant public health threats. Regular monitoring of ESBL-producing E. coli frequency and antimicrobial resistance profile in retail meat products is crucial to enhance their safety. AgNPs-H2O2 is a promising alternative for treating MDR ESBL-producing E. coli infections and reducing antimicrobial resistance risks.

Antimicrobial Effect of Silver Nanoparticles and Combination with Cotrimoxazole against Salmonella Typhi in Vitro and in Animal Model

Introduction: Salmonella typhi is a large group of gram-negative bacilli with Enterobacteriaceae and common pathogens between humans and animals, which is the main cause of typhoid fever in humans. One of the most common antibiotics in the treatment of Salmonella is cotrimoxazole, but due to the widespread use of antibiotics, bacterial resistance has developed. The aim of this study was to investigate the antibacterial effect of silver nanoparticles and its combination with the antibiotic cotrimoxazole to produce a more effective antimicrobial drug against Salmonell typhi.&#x0D; Methods: In this experimental study, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for silver nanoparticles and combination with cotrimoxazole, was performed based on microdilution method. Then, their antibacterial effects were investigated in infected mouse model. In order to analyze the results statistically, SPSS software version 16 was used. In this test, P&lt; 0.05 was considered as a significant level.&#x0D; Results: MIC and MFC of silver nanoparticles for Salmonella typhi were 4 ppm and 8 ppm respectively, composition of silver nanoparticles with cotrimoxazole for Salmonella typhi were 62 ppm and 125 ppm and cotrimoxazole for Salmonella typhi were 500 ppm and 1000 ppm. Mouse model to study the antibacterial effect of silver nanoparticles and combination with cotrimoxazole against Salmonella typhi infection was confirmed., Silver nanoparticles had the highest antibacterial effect and cotrimoxazole has the lowest antibacterial effect than other groups.&#x0D; Conclusion: Silver nanoparticles are very effective compared to other groups, especially the antibacterial cotrimoxazole.

Study of the capillary blood flow of the mucous membrane of the peri-implant area by laser Doppler flowmetry

Aim: to conduct a clinical analysis of the capillary blood flow of the mucous membrane of the peri-implant zone using laser Doppler flowmetry (LDF), as well as a comparative assessment of the effectiveness of the implanted structure with a surface, modified with silver nanoparticles (AgNP). Materials and methods. The study involved 40 patients undergoing rehabilitation for secondary partial adentia by the method of dental implantation. The examinees were divided into 2 groups: Group 1 (20 patients) – gingival formers with a surface modified by plasma electrooxidation and doped with AgNP were installed; Group 2 (20 patients) – standard gingival formers of the used implant system with a polished surface were installed. A control group (20 patients) was formed to determine the reference values. In total, 60 patients were involved in the study. Blood flow velocity in the studied groups was determined by laser Doppler flowmetry. Results. On the 10th day, when using gingival formers with a surface containing AgNP, a positive trend with increasing the blood flow rate of the mucous membrane of the peri-implant zone (6.97 mm/s) is determined, in contrast of using the gingival formers with a polished surface (5.425 mm/s). In the process of using the gum formers with a surface containing AgNPs, an increase in capillary blood flow rate (by 22.2 %) in a separate location is evidence of a reduction in inflammatory processes and a pronounced anti-inflammatory effect of the AgNP surface. Conclusions. Higher (by 22.2 %) indicators of capillary blood flow rate of the mucous membrane of the peri-implant zone in patients using gingival formers containing AgNP, compared to polished formers, indicates a pronounced anti-inflammatory effect of the proposed AgNP-doped surface. The values obtained in the group with AgNPs are as close as possible to the reference indicators of the blood flow rate in the capillary channel of the marginal gingiva of healthy people, which suggests the presence of a pronounced antimicrobial effect of silver nanoparticles on the surface of the gingival formers. Since blood flow in tissues is directly related to oxygenation of cells, reduction of local acidosis, reduction of inflammatory reactions and determines the state of tissue immunity, as well as directly affects the quality of reparative processes in damaged tissue, the obtained results allow recommending the proposed AgNP – surface for use in clinical practice.

Antimicrobial effect of silver nanoparticles on polypropylene and acrylic resin denture bases.

The investigation of the antimicrobial action of Ag solutions in different surfaces has been performed, however, there is little data on the direct addition of those particles to the polypropylene denture base. The aim of this study was to evaluate the antimicrobial effect of silver nanoparticles in Candida albicans and Streptococcus mutans colonization in acrylic resin and polypropylene denture bases. Twenty test bodies (10×13×3 mm) were fabricated with (heat-polymerized) poly methyl methacrylate acrylic resin (group 1), (heat-polymerized) poly methyl methacrylate acrylic resin with silver nanoparticles (group 2), polypropylene (group 3) and polypropylene with silver nanoparticles (group 4). Candida albicans and Streptococcus mutans colonization were performed. A colony count was performed in Colony Forming Unit (CFU/ml) and registered to calculate the arithmetical mean of the duplicate values of each sample. Data was analyzed by Lilliefors test and since samples did not present a normal distribution, Kruskal-Wallis for variance analysis with the value of significance set at p<0.05. For Candida albicans colonies, when comparing nano-Ag in polypropylene, there were statistical difference between groups 3 and 4. For the same type of growth in heat-polymerized PMMA resin with and without nano-Ag, no statistical differences were found. The presence of nanoparticles did not affect Streptococcus mutans growth in the heat-polymerized PMMA resin. Value differences of S. mutans were not significant for comparisons between groups 1-2 and 3-4. Silver nanoparticles presented antifungal activity against C. albicans in polypropylene surfaces, but not in the heat-polymerized PMMA resin. Silver nanoparticles did not present antibacterial activity against S. mutans in any of the analyzed surfaces. Key words:Removable Partial Denture, Candida, Streptococcus mutans.

Hemolytic Activity, Cytotoxicity, and Antimicrobial Effects of Silver Nanoparticles Conjugated with Lincomycin or Cefazolin.

The overuse of antibiotics has led to the emergence of resistant bacteria. A good alternative is silver nanoparticles, which have antibacterial activity against Gram-negative and Gram-positive bacteria, including multidrug-resistant strains. Their combination with already known antibiotics has a synergistic effect. In this work, we studied the synthesis of conjugates of silver nanoparticles with two antibiotics, lincomycin and cefazolin. Albumin and glutathione were used as spacer shells with functional groups. The physicochemical properties of the obtained conjugates, their cytotoxicity and synergism of antimicrobial activity were studied. The 50% antimicrobial activity of the obtained samples was shown, which allows them to be recommended for use as topical drug preparations.

Synergetic Antimicrobial Effect of Silver Nanoparticles Conjugated with Iprodione against Valsa mali.

Apple tree canker induced by Valsa mali is a vital disease in apple production around the world, and it highlyimpacts the development of apple industry. It is of great significance to study the inhibition effect of common fungicides and develop new fungistats for comprehensive control of apple tree canker. In this experiment, the inhibition activity of five fungicides, including mancozeb, metalaxyl, iprodione, prochloraz, and difenoconazole along with biosynthesized nanosilver against V. mali, were measured with the mycelium growth rate and agar well diffusion methods. The results showed that iprodione exhibited the best inhibitory effect, the median inhibition concentration (IC50) of iprodione and nanosilver was 0.62 μg.mL−1 and 45.50 μg.mL−1, the suppression rate achieved 67.93% at 200 μg.mL−1 of nanosilver. Moreover, a remarkable additive and synergistic antimicrobial effect was verified when silver nanoparticles were conjugated with iprodione at 9:1, 8:2, 7:3, and 6:4 (v/v), and the toxicity ratio was 1.04, 1.13, 1.01, and 0.98, respectively. It is proven that biosynthesized silver nanoparticles could effectively inhibit Valsa mali, and it is possible to develop and screen silver nanoparticle-based nano pesticides to manage plant diseases synthetically.

A review, tabulation of the Antimicrobial Effect of Silver Nanoparticles

Silver nanoparticles are used in every single aspect of science including medical and pharmaceuticals, as they have high antimicrobial effects because of their large surface area to volume ratio, which is the curiosity of new researchers on antibiotics, the growing microbial resistance and the development of resistant strains. Silver nanoparticles are the superabundant antimicrobial agent for bacteria, fungi, algae and are less noxious to human cells than bacterial cells. Silver nanoparticles are used to control germination in a variety of applications, such as antibacterial coating for medicinal materials to promote wound healing and prevent infection, and antibacterial vaccines to control bacterial diseases. In the current work, a review of the antimicrobial properties of silver nanoparticles is compiled in tabular form reported by different research groups. The aim of this review is to discuss the present state of affairs and suggestions for future possibilities in this field.

The antimicrobial effect of silver nanoparticles coated with silica against human pathogenic bacteria and fungi

The antibacterial property of silver (Ag) has been known since ancient time. It is reported in the literature that silver nanoparticles (AgNPs) exhibit improved antibacterial and antifungal properties in comparison to silver ions of equivalent metallic Ag concentration.A simple method has been used based on solenoid soles for the synthesis of nanoparticles of silver coated on silica. AgNPs were compared positively with silver nitrate solution and ampicillin standard antibiotics at a concentration of 50μg / mL (Table 1 and 2). AgNPs mentioned in the silica activity exhibited more than standard silver nitrate and antibiotics. AgNPs were fairly toxic to Salmonella sp., Neisseria sp., Klebsiella sp., and Pseudomonas sp. with an inhibition zone 21, 24, 16, 23 mm respectively. AgNPs exhibited strong antifungal activity against fungal strains (Candida sp., Aspergillus fumigatus and Aspergillus flavus) in different concentrations such as 30-50 and 60 μg/ml were examined for antifungal activity. AgNPs revealed the highest antifungal activity with the inhibition zone 26, 25 and 22 mm respectively. Results of the present study prevealed that AgNPs have a remarkable potential as antimicrobial agent in treating infectious diseases.

Self-defense mechanisms of microorganisms from the antimicrobial effect of silver nanoparticles: Highlight the role of extracellular polymeric substances

Silver nanoparticles (AgNPs) are nowadays widely utilized in various fields due to their unique antimicrobial properties. Extracellular polymeric substances (EPS) excreted by microorganisms might affect the transformations and antibacterial efficacy of AgNPs. In the present study, the effects of EPS released by Escherichia coli (E. coli) on the dissolution and sulfidation of AgNPs as well as the associated growth inhibition to E. coli were systematically investigated. The formation of EPS-corona caused the reduced exposure of (111) facets of AgNPs due to the preferential binding with aromatic protein components in EPS. The EPS inhibited AgNPs dissolution, while facilitated reductive transformation of the released Ag+ to Ag0 under simulated sunlight. Additionally, EPS enhanced the colloidal stability and reduced electrostatic repulsive of AgNPs, which favored the access of sulfide and significantly promoted the sulfidation of AgNPs under simulated sunlight, further reducing the available dissolved Ag+ ions. Consequently, the EPS relieved the antibacterial activity of AgNPs to E. coli. These findings highlight the importance of microbial EPS in the transformations and bactericidal effect of AgNPs, which provide clues for the development of AgNPs-based antibacterial strategies.

Overcoming Antibiotic Resistance: Playing the 'Silver Nanobullet' Card.

Enhancing the antibacterial activity of old antibiotics by a multitarget approach, such as combining antibiotics with metal nanoparticles, is a valuable strategy to overcome antibacterial resistance. In this work, the synergistic antimicrobial effect of silver nanoparticles and antibiotics, immobilized on a solid support, was investigated. Nanometric layered double hydroxides (LDH) based on Zn(II) and Al(III) were prepared by the double microemulsion technique. The dual function of LDH as an anionic exchanger and support for metal nanoparticles was exploited to immobilize both silver and antibiotics. Cefazolin (CFZ), a β-lactam, and nalidixic acid (NAL), a quinolone, were selected and intercalated into LDH obtaining ZnAl-CFZ and ZnAl-NAL samples. These samples were used for the growth of silver nanoparticles with dimension ranging from 2.5 to 8 nm. Silver and antibiotics release profiles, from LDH loaded with antibiotics and Ag/antibiotics, were evaluated in two different media: water and phosphate buffer. Interestingly, the release profiles are affected by both the acceptor media and the presence of silver. The synergistic antibacterial activity of LDH containing both silver and antibiotics were investigated on gram-positives (Staphylococcus aureus and Streptococcus pneumoniae) and gram-negatives (Pseudomonas aeruginosa) and compared with the plain antimicrobials and LDH containing only antibiotics or silver.

Control of Healthcare-Associated Infections using Silver Nanoparticles in Radiology.

Aims:The control of healthcare-associated infections (HCAIs) is a significant concern in the field of radiology due to multiple contact-transmitted pathogens on imaging devices. The antimicrobial effects of silver nanoparticles (AgNPs) in preventing HCAIs and their effects on imaging quality were evaluated.Methods:The antimicrobial effects of AgNPs were tested on prevalent contact-transmitted pathogens present in radiology examination rooms, including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), Pseudomonas aeruginosa, and Acinetobacter baumannii. Furthermore, we investigated the effects of AgNPs on X-ray image quality using humanoid head and hand phantom.Results:AgNPs did not affect the quality of X-ray images. They had antimicrobial effects against Gram-positive Bacillus, including MRSA, VRE, and Gram-negative Bacillus, including P. aeruginosa and A. baumannii.Conclusion:AgNPs are considered effective in controlling HCAIs in radiology through sterilization by coating shooting devices and accessories where physical contact between patients and healthcare professionals is frequent.

Green synthesis and antimicrobial effects of silver nanoparticles by pumpkin cucurbita maxima fruit fiber

Green synthesis and antimicrobial effects of silver nanoparticles by pumpkin cucurbita maxima fruit fiber

In English

The addition of silver ions or nanoparticles to impart antimicrobial properties to polymeric or other materials is a widely used method. However, it should be noted that the antiviral and antimicrobial effect of silver nanoparticles that come into contact with the environment, associated with their size, with a decrease in the size of nanoparticles, their effectiveness increases sharply. In the present work, we used a biodegradable polymer polylactide (PLA), which is obtained by condensation of lactic acid or ring-opening polymerization of lactide. These studies will further contribute to the development of new safe materials, in particular for food packaging, which is undoubtedly an urgent problem. The work aims is to obtain the silver-containing polymer composites based on polylactide by thermochemical reduction of Ag+ ions using natural (chitosan) and synthetic (polyethyleneimine (PEI)) polymers and to study the structure, morphology, thermomechanical and antimicrobial properties of the obtained nanocomposites. Thermochemical reduction of Ag+ ions in the bulk of polymer films, containing PLA, silver palmitate as a precursor of Ag NP and reducing agent (PEI or chitosan), has been performed by keeping them at 100–170 °C within 5 minutes. The polymeric film composites, cast from chloroform solution, were heated in an oven using precise thermal regulator VRT-3. As a result of reduction, the films get attained silver color, the Ag content in the bulk of films varied from 1 to 4 wt. %, and the thickness of the films was 110 μm. Structure, morphology, thermomechanical and antimicrobial properties of two types of nanocomposites – PLA-Ag-PEI and PLA-Ag-chitosan, formed by the thermochemical reduction of Ag+ in polymer films have been studied using wide-angle X-ray scattering (WAXS) (a DRON-4-07 diffractometer), a transmission electron microscope (TEM) (JEM-1230 JEOL, Japan), and thermomechanical analysis (a UIP-70M device). Antimicrobial activity of the obtained nanocomposites was investigated applying reference strains of opportunistic bacteria Staphylococcus aureus and Escherichia coli. It has been found that thermochemical reduction of Ag+ ions in the bulk of polymer films, when using synthetic or natural polymers (PEI or chitosan) as a reducing and stabilizing agent of silver nanoparticles occurs at 160 °C during 5 minutes. It has been found that the average size of Ag nanoparticles in the polymeric matrix is equal to ~ 7 and ~ 4 nm for PEI and chitosan, respectively. It has been shown that PLA-Ag-chitosan nanocomposites have much higher antimicrobial activity against S. aureus and E. coli strains as compared to PLA-Ag-PEI nanocomposites.

Systematic Review on Biosynthesis of Silver Nanoparticles and Antibacterial Activities: Application and Theoretical Perspectives.

The biosynthesis of silver nanoparticles and the antibacterial activities has provided enormous data on populations, geographical areas, and experiments with bio silver nanoparticles’ antibacterial operation. Several peer-reviewed publications have discussed various aspects of this subject field over the last generation. However, there is an absence of a detailed and structured framework that can represent the research domain on this topic. This paper attempts to evaluate current articles mainly on the biosynthesis of nanoparticles or antibacterial activities utilizing the scientific methodology of big data analytics. A comprehensive study was done using multiple databases—Medline, Scopus, and Web of Sciences through PRISMA (i.e., Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The keywords used included ‘biosynthesis silver nano particles’ OR ‘silver nanoparticles’ OR ‘biosynthesis’ AND ‘antibacterial behavior’ OR ‘anti-microbial opposition’ AND ‘systematic analysis,’ by using MeSH (Medical Subject Headings) terms, Boolean operator’s parenthesis, or truncations as required. Since their effectiveness is dependent on particle size or initial concentration, it necessitates more research. Understanding the field of silver nanoparticle biosynthesis and antibacterial activity in Gulf areas and most Asian countries also necessitates its use of human-generated data. Furthermore, the need for this work has been highlighted by the lack of predictive modeling in this field and a need to combine specific domain expertise. Studies eligible for such a review were determined by certain inclusion and exclusion criteria. This study contributes to the existence of theoretical and analytical studies in this domain. After testing as per inclusion criteria, seven in vitro studies were selected out of 28 studies. Findings reveal that silver nanoparticles have different degrees of antimicrobial activity based on numerous factors. Limitations of the study include studies with low to moderate risks of bias and antimicrobial effects of silver nanoparticles. The study also reveals the possible use of silver nanoparticles as antibacterial irrigants using various methods, including a qualitative evaluation of knowledge and a comprehensive collection and interpretation of scientific studies.

Antimicrobial Effect of Silver Nanoparticles Synthesized with Bougainvillea Glabra Extract on Staphylococcus Aureus and Escherichia Coli

Considering the antimicrobial properties of silver and its enhanced level at nanoscale scale, it can be used to combat the various pathogens and microbial agents. The aim of this study was to investigate the antimicrobial effect of silver nanoparticles synthesized with Bougainvillea Glabra extract on standard strains of Staphylococcus aureus and Escherichia coli. In this study, silver nanoparticles were biosynthesized using the aquatic Bougainvillea Glabra extract under optimal conditions. The synthesis of silver nanoparticles was confirmed using UltraViolet-Visible (UV-Vis) spectroscopy and X-Ray Diffraction (XRD). Based on the X-ray diffraction pattern, the silver nanoparticles crystallite size was 21 nanometers. Transmission Electron Microscopes (TEMs) and Scanning Electron Microscopes (SEM) showed the synthesis of silver nanoparticles of about 23 nm in size and spherical morphology. Revitalizing and stabilizing agent groups were identified using Fourier-Transform InfraRed (FT-IR) spectroscopy. The mean diameter of the inhibition zone and the Minimum Inhibitory Concentration (MIC) were 27.6 mm and 3.12μg/mL for S. aureus and 19.3mm and 12.5μg/mL for E. coli, respectively. Biological synthesis using Bougainvillea Glabra aquatic extract is a very inexpensive and cost-effective method. The ability of Bougainvillea Glabra to synthesize silver nanoparticles makes it possible to use this plant as a useful biological source for the synthesis of silver nanoparticles with suitable and practical sizes for medical and microbicide applications.

Ecological Method for the Synthesis, Characterization and Antimicrobial Effect of Silver Nanoparticles Produced and Stabilized with a Mixture of Mucilage/Proteins Extracted from Flaxseed

A simple and ecologically friendly method was used for the synthesis of mucilage/proteins (M/P) stabilized silver nanoparticles (M/Proteins-s-AgNPs). M/P-s-AgNPs were synthesized by reduction of Ag (from AgNO3) to Ag with M/P extracted from flaxseed. M/P-s-AgNPs were characterized by UV–Vis spectroscopy, X-ray diffraction, Infrared spectroscopy, and scanning electron microscopy techniques. The silver nanoparticles (AgNPs) obtained were in a size range of 1–60 nm. The antimicrobial activity of M/P-s-AgNPs was measured against the Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus strains using disc susceptibility, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). From the results of the disk diffusion tests, MIC, and the MBC, the maximum effectiveness of M/P-s-AgNPs was observed against E. coli, followed by P. aeruginosa and S. aureus. Therefore, it is assumed that the developed mucilage/proteins/AgNPs complex developed may have future applications as a biocide in health and medical fields.

Antimicrobial Efficacy of Silver Nanoparticles as Root Canal Irrigant's: A Systematic Review.

Removal of microbes is imperative during endodontic therapy. Due to their antimicrobial property, silver nanoparticles have been used for endodontic irrigation of the root canals. The objective of the present study was to provide a qualitative analysis of the published literature assessing silver nanoparticles as root canal irrigants. A search of PubMed, SCOPUS, Web of Science, and Embase databases was done without any time restriction. Articles published in English were included. Data were extracted and the risk of bias was assessed. Of the 154 studies identified, after screening according to the inclusion criteria, five in vitro studies were included. The results indicate that silver nanoparticles have an anti-microbial effect to varying degrees depending on certain factors. Within the limitations of the present studies that have a moderate to low risk of bias, an antimicrobial effect of silver nanoparticles is observed. Silver nanoparticles have the potential to be used as endodontic irrigants, although their efficacy depends on particle size and the duration of contact which require further investigation.

Antimicrobial effects of silver nanoparticles and extracts of Syzygium cumini flowers and seeds: Periodontal, cariogenic and opportunistic pathogens

ObjectiveThis study aimed to analyze the antimicrobial effects of lyophilized hydroalcoholic extract (HEScSeed and HEScFlower) and silver nanoparticles (AgNPs-HEScSeed and AgNPs-HEScFlower) of S. cumini seed and flower, and to characterize some compounds of these extracts and their NPs. DesignPhytochemical screening was performed by GC–MS. Nanoparticles were characterized by UV–vis spectroscopy, energy-dispersive X-ray (EDX) spectrophotometry, scanning electron microscopy (SEM) and field emission gun (FEG), dynamic light scattering (DLS) and zeta potential (ZP). Antimicrobial susceptibility tests were analyzed by broth microdilution and agar diffusion methods. ResultsHEScSeed and HEScFlower showed 7 and 17 phytochemical compounds, respectively. AgNPs-plant extracts were reported as stable and with variable shapes and sizes. All studied species (A. naeslundii, C. albicans, F. nucleatum, S. aureus, S. epidermidis, S. mutans, S. oralis and V. dispar) were susceptible to extracts and AgNPs-plant extracts, with varying degrees of antimicrobial activities (extract: 648.4−5,187.5 μg/mL; AgNPs-plant: 31.2−2,000 μg/mL). ConclusionThe extracts of S. cumini seed and flower have antimicrobial action against pathogens of medical and dental interest, whose MIC and MMC are species-dependent. The AgNPs-HEScSeed and AgNPs-HEScFlower have different shapes, sizes, organic compounds, stability and electronegativity (capping), characteristics that contribute to their bacteriostatic and fungistatic effects, but at significantly lower concentrations than plant extracts.