Silver nanoparticle embedded copper oxide as an efficient core–shell for the catalytic reduction of 4-nitrophenol and antibacterial activity improvement

Excellent As(iii) uptake and antibacterial activities of Ag/Ag2O core/shell and multi-layered graphene nanostructures obtained with the aid of Dragon's blood.

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Multifunctional Chitosan-Copper Oxide Hybrid Material: Photocatalytic and Antibacterial Activities

International Journal of Photoenergy ◽

10.1155/2013/245646 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 26

Author(s):

Yuvaraj Haldorai ◽

Jae-Jin Shim

Keyword(s):

Antibacterial Activity ◽

Copper Oxide ◽

Hybrid Material ◽

Uv Light ◽

Chemical Precipitation ◽

Antibacterial Activities ◽

High Photocatalytic Activity ◽

Precipitation Method ◽

Light Illumination ◽

Tem Analysis

Chitosan (CS) anchored copper oxide (CuO) hybrid material was prepared by chemical precipitation method. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the formation of CS-CuO hybrid. Transmission electron microscopy (TEM) analysis showed the immobilization of CuO nanoparticles on the surface of CS. The hybrid was also characterized by thermogravimetric analysis (TGA) and zeta potential. The hybrid exhibited high photocatalytic activity as evident from the degradation of methylene blue (MB) dye. The result revealed substantial degradation of the MB dye (84%) under UV-light illumination. The antibacterial activity of hybrid againstEscherichia coliwas examined by colony forming units. It was proved that the CS encapsulated CuO hybrid exhibited excellent antibacterial activity.

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Antibacterial Properties of Titanate Nanofiber Thin Films Formed on a Titanium Plate

Journal of Nanomaterials ◽

10.1155/2013/476585 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Mitsunori Yada ◽

Yuko Inoue ◽

Iwao Noda ◽

Tomohiro Morita ◽

Toshio Torikai ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Antibacterial Activity ◽

Silver Nanoparticle ◽

Antibacterial Properties ◽

Sodium Titanate ◽

Antibacterial Activities ◽

Ultraviolet Rays ◽

Titanium Plate ◽

High Antibacterial Activity

A sodium titanate nanofiber thin film and a silver nanoparticle/silver titanate nanofiber thin film formed on the surface of a titanium plate exhibited strong antibacterial activities against methicillin-resistantStaphylococcus aureus, which is one of the major bacteria causing in-hospital infections. Exposure of the sodium titanate nanofiber thin film to ultraviolet rays generated a high antibacterial activity due to photocatalysis and the sodium titanate nanofiber thin film immediately after its synthesis possessed a high antibacterial activity even without exposure to ultraviolet rays. Elution of silver from the silver nanoparticle/silver titanate nanofiber thin film caused by the silver ion exchange reaction was considered to contribute substantially to the strong antibacterial activity. The titanate nanofiber thin films adhered firmly to titanium. Therefore, these titanate nanofiber thin film/titanium composites will be extremely useful as implant materials that have excellent antibacterial activities.

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ANTIBIOTIC PROFILE AND ANTIBACTERIAL ACTIVITY OF COPPER OXIDE NANOPARTICLES AGAINST Pseudomonas fluorescens ISOLATED FROM WOUND INFECTION

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v9i3.10 ◽

2019 ◽

Vol 9 (o3) ◽

Author(s):

Haider Qassim Raheem ◽

Takwa S. Al-meamar ◽

Anas M. Almamoori

Keyword(s):

Antibacterial Activity ◽

Copper Oxide ◽

Pseudomonas Fluorescens ◽

Wide Spectrum ◽

Copper Oxide Nanoparticles ◽

Morphological Properties ◽

Clinical Samples ◽

Oxide Nanoparticles ◽

Cuo Nps ◽

Disk Diffusion Assay

Fifty specimens were collected from wound patients who visited Al-Hilla Teaching Hospital. The samples were grown on Blood and MacConkey agar for 24-48 hr at 37oC. The bacterial isolates which achieved as a pure and predominant growth from clinical samples as Pseudomonas fluorescens, were identified using morphological properties and Vitek2 system. The anti-bacterial activity of copper oxide nanoparticles (CuO NPs) against was tested by (disk diffusion assay) using dilutions of (400, 200, 100, 50, 25, and 12.5‎µ‎g/ml). The (MIC and MBC) of each isolate was determined. CuO NPs shows wide spectrum antibacterial activity against tested bacteria with rise zone of inhibition diameter that is proportionate with the increase in nanoparticle concentration. The MIC of CuO NPs extended from 100-200‎µ‎g/ml and the MBC ranged from 200-400‎µ‎g/ml. The antibiotic profile was determined by Viteck 2 compact system (Biomérieux). CuO NPs‎ found highly effective and safe in P. fluorescens wounds infections comparing with used antibiotics.

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Antioxidant and Antibacterial Activities of Artemisia herba-alba Asso Essential Oil from Middle Atlas, Morocco

Phytothérapie ◽

10.3166/phyto-2018-0057 ◽

2018 ◽

Vol 16 (S1) ◽

pp. S48-S54

Author(s):

Y. Ez zoubi ◽

S. Lairini ◽

A. Farah ◽

K. Taghzouti ◽

A. El Ouali Lalami

Keyword(s):

Antibacterial Activity ◽

Essential Oil ◽

Foodborne Pathogens ◽

Food Systems ◽

Antibacterial Activities ◽

Culture Collection ◽

Bornyl Acetate ◽

Bacterial Strains ◽

Disk Diffusion Assay ◽

Different Strains

The purpose of this study was to determine the chemical composition and to evaluate the antioxidant and antibacterial effects of the Moroccan Artemisia herba-alba Asso essential oil against foodborne pathogens. The essential oil of Artemisia herba-alba was analyzed by gas chromatography coupled with mass spectroscopy. The antibacterial activity was assessed against three bacterial strains isolated from foodstuff and three bacterial strains referenced by the ATCC (American Type Culture Collection) using the disk diffusion assay and the macrodilution method. The antioxidant activity was evaluated using the DPPH (2, 2-diphenyl-1- picrylhydrazyl) method. The fourteen compounds of the Artemisia herba-alba essential oil were identified; the main components were identified as β-thujone, chrysanthenone, α-terpineol, α-thujone, α-pinene, and bornyl acetate. The results of the antibacterial activity obtained showed a sensitivity of the different strains to Artemisia herba-alba essential oil with an inhibition diameter of 8.50 to 17.00 mm. Concerning the MICs (minimum inhibitory concentrations), the essential oil exhibited much higher antibacterial activity with MIC values of 2.5 μl/ml against Bacillus subtilis ATCC and Lactobacillus sp. The essential oil was found to be active by inhibiting free radicals with an IC50 (concentration of an inhibitor where the response is reduced by half) value of 2.9 μg/ml. These results indicate the possible use of the essential oil on food systems as an effective inhibitor of foodborne pathogens, as a natural antioxidant, and for potential pharmaceutical applications. However, further research is needed in order to determine the toxicity, antibacterial, and antioxidant effects in edible products.

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Microwave assisted synthesis of novel Pyrazole derivatives and their biological evaluation as anti-bacterial agents

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666201019152206 ◽

2020 ◽

Vol 23 ◽

Author(s):

Hadis Khodadad ◽

Farhad Hatamjafari ◽

Khalil Pourshamsian ◽

Babak Sadeghi

Keyword(s):

Antibacterial Activity ◽

Aromatic Aldehydes ◽

Catalytic Amount ◽

Antibacterial Activities ◽

Structural Features ◽

Biological Evaluation ◽

Aureus Strain ◽

Microwave Assisted Synthesis ◽

Pyrazole Derivatives ◽

Microwave Assisted

Aim and Objective: Microwave-assisted condensation of acetophenone 1 and aromatic aldehydes 2 gave chalcone analogs 3, which were cyclized to pyrazole derivatives 6a-f via the reaction with hydrazine hydrate and oxalic acid in the presence of the catalytic amount of acetic acid in ethanol. Materials and Methods: The structural features of the synthesized compounds were characterized by melting point, FT-IR, 1H, 13C NMR and elemental analysis. Results: The antibacterial activities of the synthesized pyrazoles was evaluated against three gram-positive bacteria such as Enterococcus durans, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria such as Escherichia coli and Salmonella typhimurium. Conclusion: All the synthesized pyrazoles showed relatively high antibacterial activity against S. aureus strain and none of them demonstrated antibacterial activity against E. coli.

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Novel CuO@TiO2 Core–Shell Nanostructure Catalyst for Selective Catalytic Reduction of NOx with NH3

Catalysis Letters ◽

10.1007/s10562-020-03515-2 ◽

2021 ◽

Author(s):

Jiali Zhang ◽

Hua Tian ◽

Yanke Yu ◽

Zeyu Jiang ◽

Mudi Ma ◽

...

Keyword(s):

Selective Catalytic Reduction ◽

Catalytic Reduction ◽

Core Shell ◽

Reduction Of Nox

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In Vitro Anti-Biofilm and Antibacterial Properties of Streptococcus downii sp. nov.

Microorganisms ◽

10.3390/microorganisms9020450 ◽

2021 ◽

Vol 9 (2) ◽

pp. 450

Author(s):

Maigualida Cuenca ◽

María Carmen Sánchez ◽

Pedro Diz ◽

Lucía Martínez-Lamas ◽

Maximiliano Álvarez ◽

...

Keyword(s):

Antibacterial Activity ◽

Quantitative Polymerase Chain Reaction ◽

Bacterial Load ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Oral Bacteria ◽

Periodontal Pathogens ◽

Biofilm Model ◽

Biofilm Development

The aim of this study was to evaluate the potential anti-biofilm and antibacterial activities of Streptococcus downii sp. nov. To test anti-biofilm properties, Streptococcus mutans, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans were grown in a biofilm model in the presence or not of S. downii sp. nov. for up to 120 h. For the potential antibacterial activity, 24 h-biofilms were exposed to S. downii sp. nov for 24 and 48 h. Biofilms structures and bacterial viability were studied by microscopy, and the effect in bacterial load by quantitative polymerase chain reaction. A generalized linear model was constructed, and results were considered as statistically significant at p < 0.05. The presence of S. downii sp. nov. during biofilm development did not affect the structure of the community, but an anti-biofilm effect against S. mutans was observed (p < 0.001, after 96 and 120 h). For antibacterial activity, after 24 h of exposure to S. downii sp. nov., counts of S. mutans (p = 0.019) and A. actinomycetemcomitans (p = 0.020) were significantly reduced in well-structured biofilms. Although moderate, anti-biofilm and antibacterial activities of S. downii sp. nov. against oral bacteria, including some periodontal pathogens, were demonstrated in an in vitro biofilm model.

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Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process

Materials ◽

10.3390/ma13214885 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4885

Author(s):

Aneta Święs ◽

Małgorzata Rutkowska ◽

Andrzej Kowalczyk ◽

Urbano Díaz ◽

Antonio E. Palomares ◽

...

Keyword(s):

Copper Oxide ◽

Ammonia Oxidation ◽

Catalytic Reduction ◽

Surface Acidity ◽

Selective Reduction ◽

Exchange Method ◽

Copper Species ◽

Selective Catalytic Oxidation ◽

Catalytically Active ◽

Copper Cations

Ferrierites and their delaminated forms (ITQ-6), containing aluminum or titanium in the zeolite framework, were synthetized and modified with copper by an ion-exchange method. The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD, UV-Vis DRS), textural parameters (N2-sorption), surface acidity (NH3-TPD), form and reducibility of deposited copper species (UV-Vis DRS and H2-TPR). Ferrierites and delaminated ITQ-6 zeolites modified with copper were studied as catalysts for the selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). It was shown that aggregated copper oxide species, which were preferentially formed on Ti-zeolites, were catalytically active in direct low-temperature ammonia oxidation to NO, while copper introduced into Al-zeolites was present mainly in the form of monomeric copper cations catalytically active in selective reduction of NO by ammonia to dinitrogen. It was postulated that ammonia oxidation in the presence of the studied catalysts proceeds according to the internal-selective catalytic reduction mechanism (i-SCR) and therefore the suitable ratio between aggregated copper oxide species and monomeric copper cations is necessary to obtain active and selective catalysts for the NH3-SCO process. Cu/Al-ITQ-6 presented the best catalytic properties possibly due to the most optimal ratio of these copper species.

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