Antimicrobial resistance is considered a problem for public health globally. New forms of resistance mechanisms are developing and spreading daily around the world. For that reason, a potential method for overcoming the antimicrobial resistance of several pathogens that cause deadly infections is the use of silver nanoparticles. In the present study, silver nanoparticles (AgNPs) and AgNPs conjugated with lincomycin were synthesized and characterized. The antimicrobial activity of AgNPs alone and after conjugating with lincomycin was also evaluated. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were employed to determine the morphological properties of AgNPs and AgNPs-lincomycin, which showed the average mean size was ±26.73 nm for AgNPs and ±28.31 nm for AgNPs-lincomycin with a spherical shape. In addition, the dynamic light scattering (DLS) and zeta potential were assessed. The results showed an improvement in the antimicrobial activity of lincomycin after conjugation with AgNPs, as the inhibition zone diameter reached 45.66±1.52 mm for Staphylococcus warneri, 17±2 mm for Serratia marcescens, and 22.33±1.52 mm for Candida guilliermondii. It also showed a synergistic effect of AgNPs-lincomycin against the biofilm formation of Candida guilliermondii, whereas Serratia marcescens was slightly affected. The MIC of AgNPs was 25 μg/ml for Staphylococcus warneri and Candida guilliermondii, whereas 100 μg/ml for Serratia marcescens, when the MIC of AgNPs-lincomycin was 12.5 μg/ml for Staphylococcus warneri and Candida guilliermondii, and 100 μg/ml for Serratia marcescens. In the experiment of the effect of AgNPs on gene expression of the antibiotic resistance genes, including the blaZ gene in Staphylococcus warneri, the aac(6´)-Ib-cr gene in Serratia marcescens, and the CDR1 gene in Candida guilliermondii, the results showed that there was a decrease in gene expression after being treated with AgNPs in each gene.
In this article Silver nanoparticles have been synthesized through physical method where the Nd-YAG laser has been used.The antimicrobial activities of these silver nanoparticles were investigated on two types of bacteria Escherichia coli and Staphylococcus aureus. These bacteria were used as representatives of Gram-negative and Gram-positive bacteria, respectively. Two experiments have been made The first one was to test the effectiveness of silver nanoparticles as an antimicrobial agent on Gram negative bacteria Escherichia coli and Gram positive bacteria Staphylococcus aureus, while the other one (susceptibility Test) was to evaluate antimicrobial agents effective against bacteria resistant to multiple antibiotics. This study showed t
... Show MoreThis study focused on the biological synthesis of silver nanoparticles (AgNPs), using prodigiosin pigment produced by Serratia marcescens. The effect of parameters such as pH, temperature, time, with various concentrations of silver nitrate (AgNO3) and prodigiosin on the synthesis of AgNPs were also studied. Optimized results of the biosynthesis process revealed an increase in the intensity of Surface Plasmon Resonance (SPR) bands of nanoparticles with shifting at the wavelength of 400 nm. In addition, optimum synthesis of AgNPs was achieved at pH 12, temperature 55℃, and reaction time 24 h, with concentrations of prodigiosin, as a reducing agent, of 12.5 µg/ml and silver ion concentration of 1 mM. Measuremen
... Show MoreThe plant occupied the largest area in the biosynthesis of silver nanoparticles, especially the medicinal plants, and it has shown great potential in biotechnology applications. In this study, green synthesis of silver nanoparticles from Moringa oleifera leaves extract and its antifungal and antitumor activities were investigated. The formation of silver nanoparticles was observed after 1 hour of preparation color changing. The ultraviolet and visible spectrum, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize synthesis particles. Ultraviolet and visible spectroscopy showed a silver surface plasmon resonance band at 434
... Show MoreToday technology using nanoparticle when treatment pathogentic microorganism and we focused on this here. It was found that the species of streptococcus used in present study were sensitive to erythromycin. In present study focusing biofilm formation by Streptococcus spp was evaluated. Species S. mutans was found that highest amount of biofilm compare with the other species. The aim of report effect (SNPs) on ability of biofilm form different species of streptococcus. The anti-biofilm effect of SNPs was in concentration dependent manner. The highest effect of SNP against biofilm formation was found the concentration 160 μg/ml, while the lowest effect was found the lowest used concentration (80 μg/ml) of SNPs. In vivo study revealed that s
... Show MoreBackground: The emergence and spread of multidrug-resistant Gram-negative bacilliin burn wound infections related to biofilm formation, which lend to challenge in treatment with conventional antibiotics andprompting to search for novel antimicrobial agents to control the infections.Silver nanoparticles (AgNPs) have wide spectrum biological properties with different mechanisms of action and less toxicity towards human cells.
Objective:The goal of this study was to evaluated the anti-bacterial and anti-biofilm activities of AgNPs alone and in combination with aminoglycoside (Amikacin) and β-lactam (Ampicillin) antibiotics against multidrug resistant Gram-negative bacilli (Pseudomonas aeruginos
... Show MoreThe present work investigates the synthesis of silver nanoparticles (AgNPs) by a biological method using L.Rosa flower extract and silver nitrate as precursors. Optimum conditions of synthesis were studies, such as pH, temperature, concentration of extract, concentration of silver nitrate, and stability with time. Characterization of AgNPs was carried out using UV-visible Spectroscopy, Scanning Electron Microscopy, X-Ray Diffraction, Fourier Transform Infrared and Transmission Electron Microscopy. The biosynthesized AgNPs exhibited inhibitory effects on creatine kinase activity in the sera of patients with myocardial infarction, compared with control subjects. Thermodynamic and kinetic studies of c
... Show MoreHumans are exposed to nuclear radiations every day, and these radiations are both natural and artificial. When the body tissues are exposed to nuclear radiation, free radicals are formed, which are responsible for cancer development. In this research, silver nanoparticles were synthesized by electrical explosion wire method. Nanoparticles were added to deionized water that contained free radicals before and after exposure to gamma rays. The obtained results indicate that the silver nanoparticles have antioxidant potential through possessing free radical scavenging activity, as they can donate electron to free radicals and become neutralize. Then, these nanoparticles were injected to mice before and after their irradiation with gamma ray.
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