An improved green synthesis method and Escherichia coli antibacterial activity of silver nanoparticles

2018 ◽  
Vol 182 ◽  
pp. 108-114 ◽  
Author(s):  
Pham Van Viet ◽  
Truong Tan Sang ◽  
Nguyen Ho Ngoc Bich ◽  
Cao Minh Thi
2020 ◽  
Vol 234 (3) ◽  
pp. 531-540
Author(s):  
Saba Ghamipoor ◽  
Faeze Fayyazi ◽  
Saeed Bahadorikhalili

AbstractIn this work, green synthesis of silver nanoparticles is described by phytochemical reducing silver nitrate aqueous solution using Anthemis nobilis. For this purpose, Anthemis nobilis extract was used for the synthesis of silver nanoparticles as both surfactant and reducing agent. Green synthesis method is a good alternative to physical and chemical methods, since it is fast, simple, environmentally-friendly and economic. The produced nanoparticles are identified using FE-SEM, EDX, and FT-IR and Uv/Vis techniques. Formation of silver nanoparticles is verified in 430–420 nm range. Reduction of silver ions by hydroxyl functional group is also confirmed by FT-IR device. EDX device confirms the presence of a peak for Ag element without any impurity peak. Silver nanoparticles are identified by FE-SEM device and found to have average size between 17 and 42 nm. Also, the antibacterial activity of the synthesized nanoparticles is compared with that of staphyloccusaureus and pseudomonasa aeruginosa and the maximum inhibitory activity against the bacteria is obtained using 1 mM nitrate solution.


Author(s):  
Gowri Shankar Krishnan ◽  
Namrata Pradhan ◽  
Masilamani K ◽  
Albin T Fleming

ABSTRACTObjective: In this study, silver nanoparticles (SNPs) were synthesized using an aqueous extract of Trainthema portulacastrum and silver ions (Ag+)which have been proven against certain pathogenic bacterial strains and hepatocellular carcinoma (HepG2) cell line.Methods: The bio fabricated nanoparticles were confirmed by surface plasmon resonance which were characterized by biophysical measuresutilizing the ultraviolet-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray, and transmission electron microscope(TEM), Fourier transform infrared spectroscopy, particle size analyzer, and X-ray diffraction. Antibacterial efficacy against Enterobacter aerogens,Proteus mirabilis, Escherichia coli, Staphylococcus epidermis, and Bacillus subtilis. The effect of SNPs tested against HepG2 and NIH/3T3 cell lineexhibits a dose-dependent toxicity.Results and Conclusion: The SEM and TEM images confirmed the presence of spherical and hexagonal shape (0.3-4 μm) of nanocrystalline particleswith the size range of 11.5-29.2 nm. The average particles size of SNPs is 190.3±17.0 nm. Antibacterial activity was carried out by agar well diffusionmethod against different pathogenic bacteria of which B. subtilis showed a significant zone of inhibition 8.66 mm and 12.0 mm for aqueous plantextract and synthesized SNPs. The effect of SNPs tested against HepG2 and NIH/3T3 cell line exhibits a dose-dependent toxicity. In case of HepG2, thecell viability was decreased to 50% (IC50) at the concentration of 173.8±0.84 μg/mL. From the results, it can be concluded that the SNPs fabricatedusing green synthesis method will be a promising candidate in the biomedical field, due to its high bioactive properties.Keywords: Silver nanoparticles, Trainthema portulacastrum, Antibacterial activity, Cytotoxic activity.


2019 ◽  
Vol 24 (1) ◽  
pp. 22 ◽  
Author(s):  
Tri Puji Lestari ◽  
Fitia Abbas Tahlib ◽  
Johan Sukweenadhi ◽  
Kartini Kartini ◽  
Christina Avanti

The Green Synthesis method is widely developed due to its environmentally friendly, cost-effective, and easy application for nanoparticle-scale synthesis. Among all metal nanoparticles, silver nanoparticles are the most utilized products in the field of nanotechnology. Biomolecules contained in plant extracts can reduce the size of silver particles to nano size. This study aims to determine the antibacterial properties and activity of silver nanoparticles synthesized with the ethanol extract of mahkota dewa leaves. The formation of silver nanoparticles is monitored with UV-Vis absorption and its change in color. Parameters evaluated are shape, size, particle size distribution, composition, metal residue, and a functional group of nanoparticles, using Scanning Electron Microscopy (SEM), Particle Size Analyzer (PSA), X-Ray Diffraction (XRD), and Fourier Transform InfraRed (FTIR) instrument. The research on UV-Vis color and absorption show black silver color with the wavelength of 450-465nm. The characterization result shows spherical-shaped silver nanoparticle. Furthermore, PDI best value on concentration of 0.125% is 0,221±0,0482 with average particle size of 130,300±12,6858 nm. The diffraction pattern of silver nanoparticle with XRD test indicates that the nanoparticles contain the silver component. Antibacterial activity test shows that silver nanoparticles have a greater inhibition zone than AgNO3, and 0.125% ethanol extract of mahkota dewa leaves against Escherichia coli and Staphylococcus aureus. From the results of the study, it can be concluded that the ethanol extract from mahkota dewa leaves can be used as a bioreductor agent to produce silver nanoparticles which have greater antimicrobial activity compared to Ag and ethanol extract from mahkota dewa leaves.


AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Susanna Gevorgyan ◽  
Robin Schubert ◽  
Mkrtich Yeranosyan ◽  
Lilit Gabrielyan ◽  
Armen Trchounian ◽  
...  

AbstractThe application of green synthesis in nanotechnology is growing day by day. It’s a safe and eco-friendly alternative to conventional methods. The current research aimed to study raw royal jelly’s potential in the green synthesis of silver nanoparticles and their antibacterial activity. Royal jelly served as a reducing and oxidizing agent in the green synthesis technology of colloidal silver nanoparticles. The UV–Vis maximum absorption at ~ 430 nm and fluorescence emission peaks at ~ 487 nm confirmed the presence of Ag NPs. Morphology and structural properties of Ag NPs and the effect of ultrasound studies revealed: (i) the formation of polydispersed and spherical particles with different sizes; (ii) size reduction and homogeneity increase by ultrasound treatment. Antibacterial activity of different concentrations of green synthesized Ag NPs has been assessed on Gram-negative S. typhimurium and Gram-positive S. aureus, revealing higher sensitivity on Gram-negative bacteria.


Sign in / Sign up

Export Citation Format

Share Document