Activity Of Silver Nanoparticles Research Articles

Green synthesis, characterization, and antibacterial activity of silver nano particles against some bacterial isolates

Nanotechnology has emerged as a promising field for the development of novel antibacterial agents with reduced environmental impact. In this study, we present a novel green synthesis approach for the production of silver nanoparticles (AgNPs) using a plant-based extract. These AgNPs were subsequently characterized using various analytical techniques, including UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR). UV-Vis spectroscopy confirmed the formation of AgNPs by exhibiting a characteristic surface plasmon resonance peak at around 401 and 420 nm. XRD analysis revealed the crystalline nature of the AgNPs, with distinct diffraction peaks corresponding to the face-centered cubic structure of silver. TEM analysis demonstrated that the synthesized AgNPs were predominantly spherical in shape and exhibited an average size within the nanoscale range. FTIR analysis was employed to elucidate the potential bioactive compounds present in the plant extract responsible for the reduction and stabilization of AgNPs. Furthermore, we evaluated the antibacterial activity of these synthesized AgNPs against a panel of bacterial isolates. All the bacterial isolates were sensitive to the silver nanoparticles. Staphylococcus aureus as found to be most resistant, while E. coli as found to be the most sensitive.

Antibacterial and Anti-Biofilm Activities of Silver Nano Particles Conjugated to Chitosan Against Multi-Drug Resistant Bacteria.

Nowadays, most of the traditional and conventional antibiotics are not effective against drug resistant bacterial strains. The emergence and spread of drug resistant bacterial cells calls for new therapeutic agents and strategies to control and treat the infections caused by these bacteria. In this regard, the application of nano-technology in medicine is an interesting approach. Therefore, the aim of this study was to evaluate the antibacterial and anti-biofilm activities of Ag Np conjugated to chitosan against multidrug resistant isolates of Staphylococcus aureus and Acinetobacter baumannii. Synthesis of the Ag Np and chitosan Np were performed according to the Turkevich and Ionic gelation methods, respectively. Then conjugation of nanoparticles was carried out by standard method. FTR analysis and transmission electron microscopy were used for validation of nanoparticle conjugation. Twenty clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and 20 clinical isolates of carbapenem resistant Acinetobacter baumannii (CRAB) were obtained from the microbial bank of Imam Khomeini hospital of Tehran, Iran. MIC values of the nanoparticles alone and in conjugation were determined using the microbroth dilution method. Then, fractional inhibitory concentration of agents was concluded by standard method. Finally, anti-biofilm activities of the conjugated Ag Np-chitosan at sub-MIC concentrations was tested against bacterial isolates. Synthesis of Ag Np resulted in the formation of nanoparticles with 10 nm dimensions. MIC90 of the chitosan, Ag Np and their conjugated form were respectively 64, 16, and 8 μg/mL against CRAB isolates. Also, MIC90 of the tested agents, in the same order as mentioned above, were 32, 16, and 4 μg/mL against MRSA. Combination of the agents had additive (0.625) and synergistic (0.375) effects against CRAB and MRSA. Ability of biofilm formation was dramatically reduced by ¼ MIC concentration (2 μg/mL) against the CRAB and ½ MIC concentration (2 μg/mL) in the case of the MRSA isolates. Ag Np-chitosan conjugation, an ideal alternative for ineffective antibiotics, exhibits great antibacterial and anti-biofilm effects against CRAB and MRSA isolates.

Antibacterial action of Silver Nanoparticles against Staphylococcus aureus Isolated from wound infection

This study aimed to assess antibiotics resistance and antibacterial action of silver nanoparticles against Staphylococcus aureus isolated from wound infection. A total of 100 samples of wound swab existed calm since wound patients who stayed the Al-Hillah, Teaching Hospital (wound unit) in, Babylon province, Iraq. S aureus was recognized biochemically and morphologically. A whole of 30(30%) of the whole specimens tested confident for S.aureus. Available of 30 S.aureus isolates, 8(26.6 percent) were MRSA. Antibiotic susceptibility for 8 antibiotics for MRSA that appeared to Penicillin G and Cefoxitin was tested, and all isolates were resistant (100percent), Were susceptible to Rifampin, Tetracycline, and Ciprofloxacin (62.5percent) Clindamycin sensitivity remained experimental in 75% isolates. Resistance to Erythromycin remained establish in approximately 62.5 percent of the population. Gentamycin resistance was found in 50% of the isolates. The antibacterial activity of silver nanoparticles (AgNPs) alongside S.aureus demonstrates extreme broad-range antibacterial act in contradiction of recognized bacteria, with an rise inhibition zone diameter related to nanoparticle concentration The MIC of Ag NPs ranged from 50 to 100g/ml, while the MBC ranged from 100 to 200g/ml. Ag NPs is suggested as an effective anti-MRSA alternative. This experiment discovered that Ag NPs is highly recommended as an alternative anti-MRSA agent with significant inhibitory and antibacterial effect due to the methicillin resistant strains' high rate of resistance to Penicillin G and Cefoxitin (100%), Erythromycin (62.5%), and Gentamycin resistance (50%).

Green Synthesis and Antibacterial Activities of Silver Nano particles Mediated by Extract of Cucurbita maxima (Pumpkin) Fruit Pith

Synthesis of silver nanoparticles (AgNPs) has become a necessary field of applied science. Biological method for synthesis of AgNPs by cucurbita maxima fruit pith extracts was used. The AgNPs were identified by UV–visible spectrometry; X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FT-IR). The presence of surface plasmon band around 420 nm indicates AgNPs formation. Parameter optimization showed the smallest size of AgNPs (2.86 ± 0.3 nm) was obtained with 0.1 M AgNO3 at 40oC. The present study provides the proof that the molecules within aqueous cucurbita maxima fruit pith extracts facilitate synthesis of AgNPs and highlight on value-added from cucurbita maxima fruit pith and fruit peel extracts for cost effectiveness. Also, eco-friendly medical and nanotechnologybased industries could also be provided. Size of prepared AgNPs could be controlled by temperature and AgNO3 concentration. Further studies are required to study effect of more parameters on size and morphology of AgNPs as this will help in the control of large scale production of biogenic AgNPs. The synthesized silver nanoparticles are screened antibacterial activities

Activity of Silver Nanoparticles against Staphylococcus spp.

Staphylococcus epidermidis is a bacterium that is part of the human microbiota. It is most abundant on the skin, in the respiratory system and in the human digestive tract. Also, Staphylococcus aureus contributes to human infections and has a high mortality rate. Both of these bacterial species produce biofilm, a pathogenic factor increasing their resistance to antibiotics. For this reason, we are looking for new substances that can neutralize bacterial cells. One of the best-known substances with such effects are silver nanoparticles. They exhibited antibacterial and antibiofilm formation activity that depended on their size, shape and the concentration used. In this review, we presented the data related to the use of silver nanoparticles in counteracting bacterial growth and biofilm formation published in scientific papers between 2017 and 2021. Based on the review of experimental results, the properties of nanoparticles prompt the expansion of research on their activity.

Antimicrobial Activity of Silver Nanoparticles on Pseudomonas aeruginosa: Influence of Particle Size Controlled through Mixed Current

Antimicrobial Activity of Silver Nanoparticles on Pseudomonas aeruginosa: Influence of Particle Size Controlled through Mixed Current

In vitro Antioxidant and Antidiabetic activity of Silver Nanoparticles Synthesized using Catharanthus roseus leaves

The green resources which are utilized for the synthesis of nano particles are eco-friendly and helps to evade the practice of elevated use of harmful chemicals. Bio synthesis of silver nanoparticles (AgNPs) using Catharanthus roseus leaves was carried out with their characterization including UV spectroscopy, FTIR and SEM analysis. Qualitative phytochemical analysis was done to observe the presence of phyto compounds. The antioxidant assay was done to assess DPPH and Reducing power activities. The in vitro antidiabetic assay (α-Amylase Inhibition Assay) and the in-silico molecular docking were performed to analyze the antidiabetic potential of Catharanthus leaves. Target proteins such as 11ß-hydroxysteroid dehydrogenase type I (11ß-HSD1; PDB ID: 1XU7), Glucagon like peptide-1 (GLP-1; PDB ID: 3IOL), Protein-tyrosine phosphatase 1B (PTP1B; PDB ID: 4Y14) were chosen for molecular docking against the ligands screened from GCMS data. The colour change, UV-vis spectrum, FTIR and SEM examination supported the characterization of AgNPs. The synthesized nano particles showed a strong in vitro antioxidant activity with good scavenging percentage of 90.88% compared to the standard which was 99.84% in DPPH assay. Similarly, the inhibition of α-Amylase activity increased with increase in concentration of biosynthesized nano particles. The docking study revealed that plant compounds present have the highest binding affinity and good hydrogen bond interactions with active site residues. Hence the activities demonstrated suggest that they could be useful in the preparation of many therapeutic agents.

Green synthesis, characterization and antibacterial activity of silver nanoparticles by Biarum chaduchrum leaf extract

Green synthesis, characterization and antibacterial activity of silver nanoparticles by Biarum chaduchrum leaf extract

Characterization and Antibacterial Activities of Silver Nanoparticles Synthesized using Black Seed (Nigella sativa)

This study examined the structural characteristics and antibacterial activities of silver nanoparticles synthesized from black seed. Aqueous and methanolic extracts of the black seeds were used to synthesize the silver nanoparticles (AgNPs). Synthesized AgNPs were characterized using UV-visible spectroscopy, Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and Energy Dispersive Spectroscopy (EDS). Antibacterial activity of the synthesized AgNPs was tested against Staphylococcus epidermidis and Klebsiella oxytoca. UV-visible spectra revealed a strong and broad surface plasmon resonance peak between 400-500nm. TEM showed that the AgNPs were spherical in shape and were well separated while XRD showed cubic and hexagonal structures of the AgNPs. EDS spectra showed that AgNPs have a weight percentage of silver as 77.98% and 84.63% for aqueous and methanolic extracts respectively. The AgNPs showed a 14-20mm zone of inhibition against the test organisms. This study showed that AgNPs can be effectively synthesized using black seed and showed moderate antibacterial activity.

In vitro Anticancer Activity of Silver Nanoparticles Biosynthesized from Seeds of Sesamum indicum Against Dalton’s Lymphoma Ascites

In vitro Anticancer Activity of Silver Nanoparticles Biosynthesized from Seeds of Sesamum indicum Against Dalton’s Lymphoma Ascites

Green-synthesis, characterization and antimicrobial activity of Silver nanoparticles from Corchorus olit orius pod coat aqueous extract

Green-synthesis, characterization and antimicrobial activity of Silver nanoparticles from Corchorus olit orius pod coat aqueous extract

Hexavalent Chromium as a Smart Switch for Peroxidase-like Activity Regulation via the Surface Electronic Redistribution of Silver Nanoparticles Anchored on Carbon Spheres.

Although some ions, due to their unique chemical properties, can regulate the enzyme-like activity of nanomaterials, it is still a huge challenge to explore the mechanism of regulation. Herein, we found that Cr6+ (CrO42-) as a smart switch can significantly increase the peroxidase-like (POD-like) activity of silver nanoparticles (Ag NPs), which were anchored efficiently on carbon spheres (Cal-CS/PEG/Ag) using amino-modified poly(ethylene glycol) (PEG) as a bridge. Density functional theory (DFT) calculations demonstrated that the addition of Cr6+ can not only adjust the surface electronic redistribution of Ag atoms but also improve the geometric structure of the adsorbed intermediate, which resulted in the optimization of free energy and change of bond lengths in the catalytic reaction process, increasing the POD-like activity of Cal-CS/PEG/Ag. Based on the Cr6+-increased POD-like activity of Cal-CS/PEG/Ag, we successfully constructed a visual sensor of Cr6+ along with quantitative analysis by the UV spectrum. The sensor has good selectivity for other 29 interfering ions and molecules with a detection limit of 79 nM. In this work, the detailed mechanism of the Cr6+-increased POD-like activity of Ag NPs was studied and a new possibility for the rational design of ion visual sensors using nanomaterials was proposed.

Synthesis, characterization and determination of antimicrobial activities of silver nanoparticles derived from black cabbage (Brassica oleracea L.) leaf waste

Synthesis, characterization and determination of antimicrobial activities of silver nanoparticles derived from black cabbage (Brassica oleracea L.) leaf waste

Biosynthesis, characterization and antibacterial activity of silver nanoparticles against ESBL producing water-borne pathogens

In the present work, biosynthesis of silver nanoparticles (AgNPs) using isolate of Shigella sp. AS8 culture supernatant as a reducing agent has been demonstrated. Synthesis of AgNPs was completed within 180 min of incubation at 35 °C under bright light condition. The biosynthesized nanoparticles were characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Dynamic light scattering (DLS), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive X-ray (EDX) and Atomic force microscopy (AFM). The formation of brown color reaction product with strong UV-vis spectrum absorption maxima at 411 nm due to surface plasmon resonance (SPR) indicated the synthesis of AgNPs. FTIR spectrum confirmed association of supernatant protein molecules with synthesized nanoparticles. DLS, TEM, FE-SEM and AFM showed biosynthesized nanoparticles were spherical in shape with an average size of 20 nm. EDX data analysis reveals presence of metallic silver. While, XRD analysis revealed that synthesized particles were pure and crystalline in nature. Further, AgNPs were evaluated as an antibacterial agent against extended spectrum β-lactamase (ESBL) positive water-borne pathogens. The results of present study suggest that biosynthesized AgNPs can be used to combat ESBL producing multidrug resistant bacteria. Copyright © 2016 VBRI Press

Antimicrobial activity of silver nanoparticles synthesized from fruit epicarp of Glycosmis pentaphylla(Funded Work)

Antimicrobial activity of silver nanoparticles synthesized from fruit epicarp of Glycosmis pentaphylla(Funded Work)

Green synthesis, characterization and antimicrobial activity of silver nanoparticles using Ornithogalum narbonense L.

Green synthesis of silver nanoparticles (AgNPs) was performed using extracts from Ornithogalum narbonense L. (ONL) as a cost-effective and eco-friendly approach. A surface plasmon resonance peak was observed at 440 nm after 12 h. The intense reddish-brown coloration was observed higher than 1.5 mM AgNO3 concentrations. Bioactive compounds were found responsible for the reduction, stabilization, and capping of Ag+ to AgNPs. X-ray powder diffraction analysis confirmed the face-centered cubic silver crystalline structure. The average spherical-shaped individual particle size was around 8.46 nm, while hydrodynamic size ranged between 7–13 nm and 36–131 nm. The AgNPs have good stability (ζ = –31.15 mV). Energy-dispersive X-ray spectroscopy analysis proved the presence of elemental Ag (6.76%). The antibacterial activity with the zone of inhibition is as follows: P. aeruginosa > E. coli > S.aureus > B. cereus (10.35 ± 0.12 mm > 9.40 ± 0.14 mm > 8.20 ± 0.10 mm > 7.0 ± 0.24 mm). The AgNPs did not show antifungal properties against C. albicans. HIGHLIGHTS The aqueous extract of Ornithogalum Narbonense L was used for the green synthesis of AgNPs. XRD, SEM, EDX, FTIR, ζ-potential, DLS and UV-vis characterizations were made. The average surface charge and diameter of individual AgNPs were determined as –31.15 mV and 8.46 nm. AgNPs acted as an inhibitor toward E.coli, P.aeruginosa, E.faecalis, S.aureus and B.cereus.

Antifungal Activity of Silver Nanoparticles with the Potential to Control Fungal Contamination in the Male Inflorescences of Palmyra Palm

Fungal contamination of the male inflorescences of palmyra palm (Borassus flabellifer Linn.) is a serious problem during their storage prior being used as the raw material for making the local One-Tambon-One-Product, a cloth holder known as “Nguang Taan Hom” made by the Phutaan Entrepreneurship, Takua Thung District PhangNga Province, Thailand. Morphological and molecular techniques were used to identify the isolated fungi from male palmyra palm inflorescences. Three major strains: Aspergillus niger, Aspergillus fumigatus and Aspergillus sclerotiorum were studied for antifungal activities and the minimum inhibitory concentration (MIC) of silver nanoparticles (AgNPs) was found to range from 13.5–27 mg mL–1. Then, the efficiency of the AgNPs and silver nanoparticles stabilizing by Polyvinylpyrrolidone (AgNPs-PVP) on the male palmyra palm inflorescences was studied by constructing a chamber model over a period for 9 weeks. The results showed that the group inoculated with Aspergillus niger, Aspergillus fumigatus and Aspergillus sclerotiorum spores developed fungal growth after 4 weeks whereas no fungal growth was observed in the group treated with AgNPs and AgNPs-PVP at 27 μg/ mL until week 7, indicating that dipping with either AgNPs or AgNPs-PVP is able to inhibit the growth of the fungi which cause damage to raw materials and also threaten human health. Therefore, it can effectively extend the storage time of male palmyra inflorescences.

Synthesis, Characterization and In Vitro Antibacterial Evaluation of Pyrenacantha grandiflora Conjugated Silver Nanoparticles.

In the present study, silver nanoparticles (AgNPs) were synthesized using both the chemical and biological methods and conjugated with Pyrenacantha grandiflora extracts. These were then characterized and evaluated for antimicrobial activities against multi-drug resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumonia, and Escherichia coli. Nanoparticles were analyzed with UV-visible spectrophotometer, transmission electron microscopy (TEM), and energy dispersive X-ray analysis (EDX). Silver nanoparticles, P. grandiflora extracts, and the conjugates were also analyzed with Fourier transform infrared spectroscopy (FTIR). As a result, quasi-sphere-shaped AgNPs with sizes ranging from 5 to 33 nm and spherically shaped AgNPs with sizes ranging from 3 to 25 nm were formed from chemical and biological synthesis, respectively. A well diffusion assay showed that the activity of silver nanoparticles was most improved with acetone extract against all tested bacteria with diameters in the range of 19–24 mm. The lowest MIC value of 0.0063 mg/mL against MRSA was observed when biologically synthesized AgNPs were conjugated with acetone and water extracts. Chemically synthesized silver nanoparticles showed the lowest MIC value of 0.0063 mg/mL against E. coli when conjugated with acetone and methanol extracts. This study indicates that silver nanoparticles conjugated with P. gandiflora tubers extracts exhibit strong antibacterial activities against multi-drug resistant bacterial pathogens. Therefore, biosynthesized conjugates could be utilized as antimicrobial agents for effective disease management due to the synergistic antibacterial activity that was observed.

Characterization and Antibacterial Activity of Silver Nanoparticles Biosynthesized Using Leaves Extract of Artemisia sieberi and Calotropis procera

The prevalence of antibiotic-resistant bacteria has increased recently leading to the need for novel, natural antibacterial agents such as plant-synthesized silver nanoparticles. Such synthesis is safe, cheap, rapid, non-toxic and environmentally friendly. In this study, characterization of biosynthesized silver nanoparticles from extracts of A. sieberi and C. procera was carried out using transmission electron microscopy, fourier transform infrared and energy dispersive x-ray analysis. Spherical nanoparticles with an average size was ~10 nm for A. sieberi and ~14 nm for C. procera were synthesised; synthesis was most effective using A. sieberi. Antibacterial activity of silver nanoparticles was carried out using the agar-diffusion method and by determination of the minimum inhibitory concentration. Biosynthesized silver nanoparticles showed antibacterial activity against Staphylococcus aureus, MRSA, Salmonella typhimurium and Escherichia coli, with silver nanoparticles extracts from A. sieberi being the most antibacterial.

Formulation and Characterization of Anti-Bacterial Activity of Silver Nanoparticles Using Root and Leaf of Wedelia trilobata

In the present study one such species, Wedelia trilobata, has be chosen to review the In vitro antibacterial activity of the root extract by using solvent ethanol for the selected plant Wedelia triolobata. The deduction of nanoparticles used to be unalterable by UV-Visible spectroscopy, FTIR, particle size, and zeta potential. The anti-bacterial activity of Wedelia trilobata mediated synthesis silver nanoparticles was tested by disc diffusion assay against standard organisms like Escherichia coli and staphylococcus aureus bacteria. The formation of silver nanoparticles by Wedelia trilobata was initially demonstrated by color changes confirmed by UV-Visible root exhibited a specific absorbance peak around 450 nm and leaf exhibited a specific absorbance peak around 418nm respectively. The Zeta potential of silver nanoparticles was found to be root 0.1 and leaf 0.4, so it indicates the dispersion and stability. The antibacterial activity against Gram-positive Staphylococcus aureus was increased, which was indicated by an increase in the inhibition zone diameter from 3Mm for normal (9.5Mm), standard (12.3Mm), control (11.3Mm), extraction for AgNPs Wedelia trilobata (13.8). 5Mm for normal (7.3Mm), standard (19.4Mm), control (10.5Mm), extraction for AgNPs Wedelia trilobata (19.8). The antibacterial activity against Gram-negative E.coli was increased, which was indicated by an increase in the inhibition zone diameter from 3Mm for normal (7.8Mm), standard (8.5Mm), control (10.2Mm), extraction for AgNPs Wedelia trilobata (14.3). 5Mm for normal (13Mm), standard (19.6Mm), control (15.3Mm) extraction for AgNPs Wedelia trilobata (19.8). The present investigation revealed that the ethanolic Root and aqueous leaf extracts the chosen plant have potential to suppress the expansion of infective bacterial strains.