scholarly journals Elimination of Escherichia coli in Water Using Cobalt Ferrite Nanoparticles: Laboratory and Pilot Plant Experiments

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2103
Author(s):  
Elmer Gastelo ◽  
Juan Montes de Oca ◽  
Edward Carpio ◽  
Juan Espinoza ◽  
Pilar García ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pilot Plant ◽  
Cobalt Ferrite ◽  
Ferrite Nanoparticles ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
E Coli ◽  
Cobalt Ferrite Nanoparticles

This paper focuses on the synthesis of cobalt ferrite nanoparticles by the sol–gel method and their photocatalytic activity to eliminate bacteria in aqueous media at two different scales: in a laboratory reactor and a solar pilot plant. Cobalt ferrite nanoparticles were prepared using Co(II) and Fe(II) salts as precursors and cetyltrimethyl ammonium bromide as a surfactant. The obtained nanoparticles were characterized by X-ray diffraction, scanning and transmission electron microscopy. Escherichia coli (E. coli) strain ATCC 22922 was used as model bacteria for contact biocidal analysis carried out by disk diffusion method and photocatalysis under an ultraviolet A (UV-A) lamp for laboratory analysis and solar radiation (radiation below 350 W/m2 in a typical cloudy day) for the pilot plant analysis. The results showed that cobalt ferrite nanoparticles have an average diameter of (36 ± 20) nm and the X-ray diffraction pattern shows a cubic spinel structure. Using the disk diffusion technique, it was obtained inhibition zones of (17 ± 2) mm diameter. Results confirm the photocatalytic elimination of E. coli in water samples with remaining bacteria below 1% of the initial concentration during the experiment time (30 min for laboratory tests and 1.5 h for pilot plant tests).

scholarly journals Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

2011 ◽  
Vol 2 (1) ◽  
pp. 8
Author(s):  
Ronak Bakhtiari ◽  
Jalil Fallah Mehrabadi ◽  
Hedroosha Molla Agamirzaei ◽  
Ailar Sabbaghi ◽  
Mohammad Mehdi Soltan Dallal
Keyword(s):  
Escherichia Coli ◽  
Disk Diffusion ◽  
Confirmatory Test ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Beta Lactamase ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially <em>Escherichia coli (E. coli)</em>, is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly <em>E. coli </em>is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 <em>E. coli </em>isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on <em>E. coli </em>isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) <em>E. coli </em>isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

scholarly journals Synthesis and Characterization of a Core-shell Material Using YBa2Cu3O7-d and Cobalt Ferrite Nanoparticles

2019 ◽  
Vol 69 (12) ◽  
pp. 3345-3348
Author(s):  
Maria Colie ◽  
Dan Eduard Mihaiescu ◽  
Daniela Istrati ◽  
Adrian Vasile Surdu ◽  
Bogdan Vasile ◽  
...  
Keyword(s):  
Cobalt Ferrite ◽  
Nanostructured Material ◽  
Ferrite Nanoparticles ◽  
Precipitation Method ◽  
Core Shell ◽  
Shell Material ◽  
X Ray ◽  
Cobalt Ferrite Nanoparticles ◽  
Transmission Electron ◽  
Co Precipitation

In this paper we describe the synthesis of a core-shell material using yttrium superconducting ceramic material (YBCO) and cobalt ferrite nanoparticles in order to obtain a nanostructured material with magnetic properties. The advantages of such material aim the selective deposition of nanofilms oriented in magnetic fields. To obtain this core-shell material, the solutions of the nitrates were first obtained by dissolving the salts in demineralised water. The suspension with cobalt ferrite nanoparticles was obtained by co-precipitation method. To obtain YBa2Cu3O7-�- coated magnetic nanoparticles by autocombustion reaction the solutions of nitrates and citric acid were used. The ratio of the metal ions: Y:Ba:Cu was 1:2:3, and between the oxidant and the reducing agent was used a citrate / nitrate mass ratio equal with 0.7. The final material was analyzed by X-ray diffraction (XRD), electronic scanning microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM).

scholarly journals X-ray analysis of nickel-cobalt ferrite nanoparticles by using debye–scherrer, williamson–hall and ssp methods

2016 ◽  
Vol 20 (1/2) ◽  
Author(s):  
V. S. Bushkova ◽  
S. I. Mudry ◽  
I. P. Yaremiy ◽  
V. I. Kravets
Keyword(s):  
Cobalt Ferrite ◽  
Ferrite Nanoparticles ◽  
X Ray ◽  
Cobalt Ferrite Nanoparticles ◽  
Nickel Cobalt

Preparation of A Magnetic Nanosensor Based on Cobalt Ferrite Nanoparticles for The Electrochemical Determination of Methyldopa in The Presence of Uric Acid

2020 ◽  
Vol 23 (10) ◽  
pp. 1023-1031
Author(s):  
Khadijeh Najafi ◽  
Karim Asadpour-Zeynali ◽  
Fariba Mollarasouli
Keyword(s):  
Uric Acid ◽  
Electrochemical Sensor ◽  
Cobalt Ferrite ◽  
Electrochemical Determination ◽  
Ferrite Nanoparticles ◽  
Current Response ◽  
Experimental Conditions ◽  
X Ray ◽  
Cobalt Ferrite Nanoparticles

Aim and Objective: Methyldopa is one of the medications that is used for the treatment of hypertension. Therefore, the determination of methyldopa in the presence of other biological components is essential. In this work, a promising electrochemical sensor based on CoFe2O4 magnetic nanoparticles modified glassy carbon electrode (CoFe2O4/GCE) was developed for electrochemical determination of methyldopa in the presence of uric acid. Cobalt ferrite nanoparticles were synthesized via chemical method. Materials and Methods: Characterizing the CoFe2O4 was investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), and cyclic voltammetry techniques. Results: Under the optimal experimental conditions, the current response of the electrochemical sensor obtained with differential pulse voltammetry was increased linearly in the concentration range from 1.45 to 15.1 μmol L−1 with the detection limit of 1.07 μmol L−1 for methyldopa. Also, by using the proposed method, methyldopa and uric acid could be analyzed in a mixture independently. The difference in peak potential for analytes is about 150 mV. Conclusion: The present sensor was successfully applied for the determination of methyldopa in the presence of uric acid in biological samples and the pharmaceutical samples with satisfactory results.

Synthesis and Structures of Halo-Substituted Aroylhydrazones with Antimicrobial Activity

2012 ◽  
Vol 65 (4) ◽  
pp. 343 ◽  
Author(s):  
Mei Zhang ◽  
Dong-Mei Xian ◽  
Hai-Hua Li ◽  
Ji-Cai Zhang ◽  
Zhong-Lu You
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Inhibitory Concentration ◽  
Antimicrobial Activities ◽  
X Ray Diffraction ◽  
X Ray ◽  
E Coli ◽  
Diphenyl Tetrazolium Bromide

A series of new halo-substituted aroylhydrazones have been prepared and structurally characterized by elemental analysis, 1H NMR, 13C NMR, and IR spectra, and single crystal X-ray diffraction. The compounds were evaluated for their antibacterial (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence) and antifungal (Candida albicans and Aspergillus niger) activities by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) method. Among the tested compounds, N′-(2-chloro-5-nitrobenzylidene)-2-fluorobenzohydrazide showed the most effective antimicrobial activity with minimum inhibitory concentration values of 0.82, 2.5, 1.7, 15.2, and 37.5 μg mL–1 against B. subtilis, S. aureus, E. coli, P. fluorescence, and C. albicans, respectively. The biological assay indicated that the presence of the electron-withdrawing groups in the aroylhydrazones improved their antimicrobial activities.

Overproduction, purification, crystallization and preliminary X-ray diffraction studies of the human spliceosomal protein U5-15kD

1999 ◽  
Vol 55 (4) ◽  
pp. 888-890 ◽  
Author(s):  
Klaus Reuter ◽  
Ralf Ficner
Keyword(s):  
Escherichia Coli ◽  
Data Collection ◽  
Diffusion Method ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Gene Coding ◽  
Vapour Diffusion ◽  
Spliceosomal Protein

The gene coding for the human spliceosomal U5 snRNP-specific 15 kDa protein (U5-15kD) was overexpressed in Escherichia coli, its product purified to homogeneity and crystallized. Well diffracting single crystals were obtained by the vapour-diffusion method in hanging drops and subsequent macroseeding. The crystals belong to the orthorhombic space group P21212 with a = 62.3, b = 65.7, c = 37.1 Å. They diffract to at least 3.0 Å and contain one molecule in the asymmetric unit. A selenomethionine derivative of the protein was prepared and crystallized for multiwavelength anomalous diffraction (MAD) data collection.

scholarly journals Biological synthesis of cobalt ferrite nanoparticles

2012 ◽  
Vol 2 (1) ◽  
pp. 9 ◽  
Author(s):  
Anal K. Jha ◽  
Kamal Prasad
Keyword(s):  
Room Temperature ◽  
Cobalt Ferrite ◽  
Low Cost ◽  
Ferrite Nanoparticles ◽  
Biological Synthesis ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Cobalt Ferrite Nanoparticles ◽  
Transmission Electron ◽  
Individual Nanoparticles

A low-cost green and reproducible yeast (<em>Saccharomyces cerevisiae</em>) mediated biosynthesis of cobalt ferrite nanoparticles is reported. The synthesis is performed at close to room temperature in the laboratory. X-ray, Fourier transform infrared spectroscopy and high resolution transmission electron microscopy analyses are performed to ascertain the formation of cobalt ferrite nanoparticles. Individual nanoparticles, as well as a very few aggregate having the size of 3-15 nm, were found. The vibrating sample magnetometer measurement showed superparamagnetic behavior in cobalt ferrite nanoparticles. The mechanism involved in the biosynthesis of cobalt ferrite nanoparticles has also been discussed.

Overexpression, purification, crystallization and preliminary X-ray diffraction analysis of the receiver domain of PhoB

1998 ◽  
Vol 54 (6) ◽  
pp. 1460-1463 ◽  
Author(s):  
Maria Solà ◽  
F.-Xavier Gomis-Rüth ◽  
Alicia Guasch ◽  
Luis Serrano ◽  
Miquel Coll
Keyword(s):  
Response Regulator ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
Signal Transduction System ◽  
Hanging Drop ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
E Coli ◽  
Receiver Domain ◽  
Two Component Signal Transduction

PhoB is the response regulator of the E. coli two-component signal transduction system for phosphate regulation. It is a transcription factor that activates more than 30 genes of the pho regulon. Crystals of the receiver domain of PhoB were obtained by applying the hanging-drop vapour-diffusion method. X-ray diffraction data have been collected using synchrotron radiation to 1.88 Å resolution. The crystals belong to the orthorhombic space group P212121 with unit-cell constants a = 34.11, b = 60.42, c = 119.97 Å. The Matthews parameter suggests that PhoB crystallizes with two molecules per asymmetric unit, suggesting that activating dimerization occurs in the crystal.

scholarly journals SYNTHESIS, CHARACTERIZATION OF ANTIMICROBIAL ACTIVITY OF 22’DICHLOROHYDROBENZOIN

2018 ◽  
Vol 11 (12) ◽  
pp. 334
Author(s):  
Thanuja B ◽  
Charles Kanagam
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Activities ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
E Coli ◽  
Vis Spectroscopy ◽  
Optical Behavior ◽  
Thermal Stability Of

Objective: The objective of this work to evaluate the antimicrobial activities of synthesized 22’dichlorohydrobenzoin (22’CD) a new organic crystal.Methods: 22’CD a new organic crystal was grown by vapor diffusion method. Single crystals of 22’CD have been subjected to X-ray diffraction analysis to estimate the lattice parameters and the space group. The molecular structure was confirmed using Fourier transform infrared and nuclear magnetic resonance (NMR) spectral analyses. Optical behavior and thermal stability of the crystal were determined using UV-Vis spectroscopy and thermogravimetry-differential thermal analysis curves. In the present study, antimicrobial activity of 22’CD was evaluated against Escherichia coli and Bacillus subtilis was evaluated by agar well diffusion method.Results: Antibacterial activity of 22’CD was analyzed with ciprofloxacin and miconazole standard and tested against E. coli, Pseudomonas aeruginosa, Salmonella paratyphi, Klebsiella pneumonia’s, Staphylococcus aureus, Streptococcus progenies, and B. subtilis.Conclusion: The 22’CD was found to be effective against E. coli and B. subtitles.

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