A significant increase in the incidence of non-O157 verotoxigenic Escherichia coli (VTEC) infections have become a serious health issues, and this situation is worsening due to the dissemination of plasmid mediated multidrug-resistant microorganisms worldwide. This study aims to investigate the presence of plasmid-mediated verotoxin gene in non-O157 E. coli. Standard microbiological techniques identified a total of 137 E. coli isolates. The plasmid was detected by Perfectprep Plasmid Mini preparation kit. These isolates were subjected to disk diffusion assay, and plasmid curing with ethidium bromide treatment. The plasmid containing isolates were subjected to a polymerase chain reaction (PCR) for investigating the presence of plasmid mediated verotoxin gene (VT1 and VT2) in non-O157 E. coli. Among the 137 E. coli isolates, 49 isolates were non-O157 E. coli while 29 (59.1%) isolates were verotoxin producing non-O157 serotypes and 26 non-O157 VTEC isolates possessed plasmids. Certain isolates harboured single sized plasmid while others had multiple plasmids with different size varied from 1.8kb to 7.6kb. A plasmid containing all (100%) the isolates was multidrug-resistant. Eight isolates changed their susceptibility patterns while three isolates were found to lose plasmid after post plasmid curing treatment and the rest of the isolates (15) remained constant. Different PCR sets characterized 3 plasmid-mediated verotoxins producing non-O157 E. coli. This current study demonstrated the occurrence of plasmid mediated verotoxin gene in non-O157 E. coli. To the best of our knowledge, this is the first report in the global literature on plasmid-mediated verotoxin gene in non-O157 E. coli. Timely diagnosis and surveillance of VTEC infections should prioritize to stop or slow down the virulence gene for dissemination by plasmid-mediated gene transfer amongst the same bacteria or other species.
Modified algae with nano copper oxide (CuO) were used as adsorption media to remove tetracycline (TEC) from aqueous solutions. Functional groups, morphology, structure, and percentages of surfactants before and after adsorption were characterised through Fourier-transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). Several variables, including pH, connection time, dosage, initial concentrations, and temperature, were controlled to obtain the optimum condition. Thermodynamic studies, adsorption isotherm, and kinetics models were examined to describe and recognise the type of interactions involved. Resultantly, the best operation conditions were at pH 7, contact time
... Show MoreThe synthesis, characterization and liquid crystalline properties of N4,N40-bis((1 H-benzo[d]imidazol-2- yl)methyl)-3,30-dimethyl-[1,10-biphenyl]-4,40-diamine and of their corresponding Mn(II), Fe(II), Ni (II), Cu(II), and Zn(II) complexes are described. The ligand and complexes have been characterized by elemental analysis, magnetic susceptibility measurements (meff), conductometric measurements and Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (1H NMR), (13C-NMR) and UV–Vis spectroscopy. Spectral investigations suggested octahedral coordination geometrical arrangement for M(II) complexes. The phase transition temperatures were detected by differential scanning calorimetry (DSC) analysis and the phases are confirmed by op
... Show MoreChitosan-schiff base with three different ratios of para-Dimethyl aminobenzaldehyde& chitosan Schiff base hydrogels have been prepared for controlled drug release study. The synthesized chitosan Schiff base and chitosan Schiff base hydrogel were characterized by FT-IR, UV-Visible, SEM, analysis. Swelling properties of the hydrogel were investigated at three different media pH (2, 7, 10). The swelling degree varied with the pH, amount of crosslinking agent glutaraldehyde and with the amount of paraDimethylaminobenzaldehyde for the hydrogels. All hydrogels were used for controlled drug release system. Aspirin was used as model drug, in three different buffer solution (2, 7, 10) as release media. The rate of release of drugs in the pH2 is m
... Show MoreThe process for preparing activated carbon (AC) made from tea residue was described in this paper. Investigated were the physicochemical characteristics and adsorption efficiency of the produced AC. Activation with potassium hydroxide (KOH) and carbonization at 350 °C are the two key steps in the manufacturing of AC. The activated carbon was used to adsorb Tetracycline (TC). Different parameters were studied at room temperature to show their effects on the adsorption efficiency of TC. These parameters are the initial concentration of adsorbate TC, solution acidity pH, time of adsorption, and adsorbent dosage. The prepared active carbon was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microsc
... Show MoreThis work involves synthesis of novel Schiff bases derivatives contining isoxazoline or pyrazoline units starting with chalcons . 4-Aminoacetophenone was react with pnitrobenzaldehyde or p-chlorobenzaldehyde in basic medium giving chalcones [I]a,b by claisenschemidt reactions. The chalcones [I]a,b were reacted with hydroxylamine hydrochloride giving isoxazolines [II]a,b in basic medium. The chalcone [I]a could also reacted with hydrazine hydrate to give pyrazolines [III]a . The novel Schiff bases with structural formula [VIII]n , [IX]n , [X]m and [XI]m were prepared by the reaction of amino compounds ; isoxazoline [II]a,b and pyrazolines [III]a with monoaldehydes [VI]n and dialdehydes [VII]m , respectively in dry benze
... Show MoreWe prepared polythiophene (PTH) with single wall carbon nanotube (SWCNT) nanocomposite thin films for Nitrogen dioxide (NO2) gas sensing applications. Thin films were synthesized via electrochemical polymerization method onto (Indium tin oxide) ITO coated glass substrate of thiophene monomer with magnesium perchlorate and different concentration from SWCNT (0.012 and 0.016) % in the presence130mL of Acetonitrile used. X-ray diffraction (XRD), Field Emission Scanning Electron microscopy (FE-SEM), Atomic Force Microscope (AFM) and Fourier Transform Infrared Spectroscopy (FT-IR) were used to characterized these nanocomposite thin films. The response of these nanocomposite for NO2 gas was evaluated via monitoring the change
... Show MoreNanoparticles generation by laser ablation of a solid target in a liquid environment is an easy method. Cadmium Telluride (CdTe) colloidal nanoparticles have been synthesized by laser ablation Nd:YAG with wavelengths of 1064nm and double frequency at 532 nm, number of pulses 50 pulses, with pulse energy= 620mJ, 700mJ of a solid target CdTe is immersed in double distilled deionized water (DDIW) and in methanol liquid. Influences of the laser energy and different solutions on the formation and optical characterization of the CdTe nanoparticles have been studied using atomic force microscope (AFM) and the UV-Vis absorption. As a results, it leads to the absorbance in UV-Vis spectra of samples prepared in water at laser wavelength of 532nm i
... Show MoreThe monomer phenyl acrylamide was synthesized by reacting acrylamide with chloro benzene in the presence of pyridine. Copolymer of phenyl acrylamide (PAM) with methyl methacrylate (MMA) was synthesized by free radical technique using dimethylsulfoxide (DMSO) as solvent and benzoyl peroxide (BPO) as initiator. The overall conversion was kept low (≤ 15% wt/wt) for all studies copolymers samples. The synthesized copolymers were characterized using fourier transform infrared spectroscopy (FT-IR), and their thermal properties were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The copolymers compositions were determined by elemental analysis. The monomer reactivity ratios have been calculated b
... Show MoreOily wastewater is one of the most challenging streams to deal with especially if the oil exists in emulsified form. In this study, electrospinning method was used to prepare nanofiberous polyvinylidene fluoride (PVDF) membranes and study their performance in oil removal. Graphene particles were embedded in the electrospun PVDF membrane to enhance the efficiency of the membranes. The prepared membranes were characterized using a scanning electron microscopy (SEM) to verify the graphene stabilization on the surface of the membrane homogeneously; while FTIR was used to detect the functional groups on the membrane surface. The membrane wettability was assessed by measuring the contact angle. The PVDF and PVDF / Graphene membranes efficiency
... Show MoreIn this study, tin oxide (SnO2) and mixed with cadmium oxide (CdO) with concentration ratio of (5, 10, 15, 20)% films were deposited by spray pyrolysis technique onto glass substrates at 300ºC temperature. The structure of the SnO2:CdO mixed films have polycrystalline structure with (110) and (101) preferential orientations. Atomic force microscopy (AFM) show the films are displayed granular structure. It was found that the grain size increases with increasing of mixed concentration ratio. The transmittance in visible and NIR region was estimated for SnO2:CdO mixed films. Direct optical band gap was estimated for SnO2 and SnO2 mixed CdO and show a decrease in the energy gap with increasing mixing ratio. From Hall measurement, it was fou
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