Biosynthesis of gold nanoparticles by Azospirillum brasilense

Kupryashina, M. A.; Ветчинкина, Е. П.; Буров, А. М.; Ponomareva, E. G.; Никитина, В. Е.

doi:10.1134/s002626171401007x

Cited by 22 publications

(17 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…was found to be -17.7 ± 5.3 mV. The difference in zeta potential values of metal nanoparticles, including silver and gold NPs, previously reported by authors may be connected with different conditions of synthesis process and differences between bacteria isolates [14,[57][58][59].…”

Section: Discussionmentioning

confidence: 61%

See 1 more Smart Citation

Silver and gold nanoparticles synthesized from Streptomyces sp. isolated from acid forest soil with special reference to its antibacterial activity against pathogens

et al. 2016

View full text Add to dashboard Cite

Biological systems such as bacteria, fungi or plants for synthesis of noble nanoparticles (NPs) are easy, inexpensive and eco-friendly. Obtained bioparticles due to its physico-chemical nature possess biologically active properties such as antimicrobial activity. In this study, the biological synthesis of silver (Ag) and gold (Au) nanoparticles using Streptomyces sp. strain NH21 isolated from acidic soil and its antibacterial activity against bacteria is presented. The physico-chemical properties of obtained particles were characterized. UV-Vis showed broad peak at 404 and 424 nm for AgNPs and 564 nm for AuNPs. Transmission electron microscopy studies showed small sized nanoparticles of 44 nm for supernatant and 8.4 nm for biomass synthesized AgNPs, and 10 nm for supernatant synthesized AuNPs, which was confirmed by nanoparticle tracking analyses. Fourier transform infrared spectroscopy revealed the presence of capping agents over metal-NPs. The negative Zeta potential values of metal-NPs indicated stability of biosynthesized particles. In vitro antibacterial activity and minimal inhibitory concentration of NPs was assessed against Gram-positive and Gram-negative bacteria. Unlike to gold-NPs, silver-NPs showed reliable antibacterial activity. Atomic force microscopy analysis recorded changes in cell morphology of tested bacterial strains after treatment with nanoparticles.

show abstract

Section: Discussionmentioning

confidence: 61%

“…However it is assumed that synthesized nanoparticles were moderately stable. The negatively charged nanoparticles were found in work by Fayaz et al [58] and Kupryashina et al [14]. The authors reported negative zeta potential values of synthesized nanoparticles of -8.5 and -5.08 mV, respectively.…”

Section: Discussionmentioning

confidence: 82%

Silver and gold nanoparticles synthesized from Streptomyces sp. isolated from acid forest soil with special reference to its antibacterial activity against pathogens

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Therefore, our findings are in line with these previously published. However, differences in the nanoparticle size and charge might be related to strain specificity, growth conditions of strain, and conditions used during the synthesis process (Kupryashina et al, 2013;Mohanta and Behera, 2014;Rai et al, 2016). Some subtle differences have been observed even in the same isolate (Wypij et al, 2017(Wypij et al, , 2020.…”

Section: Discussionmentioning

confidence: 99%

Green Synthesized Silver Nanoparticles: Antibacterial and Anticancer Activities, Biocompatibility, and Analyses of Surface-Attached Proteins

et al. 2021

View full text Add to dashboard Cite

The increasing number of multi-drug-resistant bacteria and cancer cases, that are a real threat to humankind, forces research world to develop new weapons to deal with it. Biogenic silver nanoparticles (AgNPs) are considered as a solution to this problem. Biosynthesis of AgNPs is regarded as a green, eco-friendly, low-priced process that provides small and biocompatible nanostructures with antimicrobial and anticancer activities and potential application in medicine. The biocompatibility of these nanoparticles is related to the coating with biomolecules of natural origin. The synthesis of AgNPs from actinobacterial strain was confirmed using UV-Vis spectroscopy while their morphology, crystalline structure, stability, and coating were characterized using, transmission electron microscopy (TEM), X-ray diffraction (XRD), Zeta potential and Fourier transform infrared spectroscopy (FTIR). Antibacterial activity of biogenic AgNPs was evaluated by determination of minimum inhibitory and minimum biocidal concentrations (MIC and MBC) against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. The potential mechanism of antibacterial action of AgNPs was determined by measurement of ATP level. Since the use of AgNPs in biomedical applications depend on their safety, the in vitro cytotoxicity of biosynthesized AgNPs on MCF-7 human breast cancer cell line and murine macrophage cell line RAW 264.7 using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, cell lactate dehydrogenase (LDH) release and measurement of reactive oxygen species (ROS) level were assessed. The nanoparticle protein capping agent that can be involved in reduction of silver ions to AgNPs and their stabilization was identified using LC-MS/MS. Nanoparticles were spherical in shape, small in size (mean 13.2 nm), showed crystalline nature, good stability (−18.7 mV) and presence of capping agents. They exhibited antibacterial activity (MIC of 8–128 μg ml−1, MBC of 64–256 μg ml−1) and significantly decreased ATP levels in bacterial cells after treatment with different concentrations of AgNPs. The in vitro analysis showed that the AgNPs demonstrated dose-dependent cytotoxicity against RAW 264.7 macrophages and MCF-7 breast cancer cells but higher against the latter than the former. Cell viability decrease was found to be 42.2–14.2 and 38.0–15.5% while LDH leakage 14.6–42.7% and 19.0–45.0%, respectively. IC50 values calculated for MTT assay was found to be 16.3 and 12.0 μg ml−1 and for LDH assay 102.3 and 76.2 μg ml−1, respectively. Moreover, MCF-7 cells released a greater amount of ROS than RAW 264.7 macrophages during stimulation with all tested concentrations of AgNPs (1.47–3.13 and 1.02–2.58 fold increase, respectively). The SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) analysis revealed the presence of five protein bands at a molecular weight between 31.7 and 280.9 kDa. These proteins showed the highest homology to hypothetical proteins and porins from E. coli, Delftia sp. and Pseudomonas rhodesiae. Based on obtained results it can be concluded that biogenic AgNPs were capped with proteins and demonstrated potential as antimicrobial and anticancer agent.

show abstract

“…Rathod et al [21] and Wypij et al [23,24] showed that AgNPs synthesized by filamentous actinobacterial strains had zeta potential in a range from −14.7 to −18.0 mV, thus similar to that found in AgNPs from strain SH11. However, it was suggested that differences in the zeta potential of biogenic nanoparticles might be related to different conditions of the synthesis process and differences between bacterial isolates [26][27][28].…”

Section: Discussionmentioning

confidence: 99%

Biogenic Silver Nanoparticles: Assessment of Their Cytotoxicity, Genotoxicity and Study of Capping Proteins

et al. 2020

View full text Add to dashboard Cite

The development of nanotechnology in the last two decades has led to the use of silver nanoparticles (AgNPs) in various biomedical applications, including antimicrobial, anti-inflammatory, and anticancer therapies. However, the potential of the medical application of AgNPs depends on the safety of their use. In this work, we assessed the in vitro cytotoxicity and genotoxicity of silver nanoparticles and identified biomolecules covering AgNPs synthesized from actinobacterial strain SH11. The cytotoxicity of AgNPs against MCF-7 human breast cancer cell line and murine macrophage cell line RAW 264.7 was studied by MTT assay, cell LDH (lactate dehydrogenase) release, and the measurement of ROS (reactive oxygen species) level while genotoxicity in Salmonella typhimurium cells was testing using the Ames test. The in vitro analysis showed that the tested nanoparticles demonstrated dose-dependent cytotoxicity against RAW 264.6 macrophages and MCF-7 breast cancer cells. Moreover, biosynthesized AgNPs did not show a mutagenic effect of S. typhimurium. The analyses and identification of biomolecules present on the surface of silver nanoparticles showed that they were associated with proteins. The SDS-PAGE (sodium dodecyl sulfate–polyacrylamide gel electrophoresis) analysis revealed the presence of 34 and 43 kDa protein bands. The identification of proteins performed by using LC-MS/MS (liquid chromatography with tandem mass spectrometry) demonstrated their highest homology to bacterial porins. Capping biomolecules of natural origin may be involved in the synthesis process of AgNPs or may be responsible for their stabilization. Moreover, the presence of natural proteins on the surface of bionanoparticles eliminates the postproduction steps of capping which is necessary for chemical synthesis to obtain the stable nanostructures required for application in medicine.

show abstract

Biosynthesis of gold nanoparticles by Azospirillum brasilense

Cited by 22 publications

References 20 publications

Silver and gold nanoparticles synthesized from Streptomyces sp. isolated from acid forest soil with special reference to its antibacterial activity against pathogens

Silver and gold nanoparticles synthesized from Streptomyces sp. isolated from acid forest soil with special reference to its antibacterial activity against pathogens

Green Synthesized Silver Nanoparticles: Antibacterial and Anticancer Activities, Biocompatibility, and Analyses of Surface-Attached Proteins

Biogenic Silver Nanoparticles: Assessment of Their Cytotoxicity, Genotoxicity and Study of Capping Proteins

Contact Info

Product

Resources

About