The spread of antibiotic resistant bacteria is a worldwide problem. Due to the importance of P. aeruginosa as a multidrug resistant bacterium, this study aimed, through molecular techniques, to detect point mutations in chromosomal genes responsible for the quinolones class of antibiotics resistance. A total of 52 isolates from burn infections were identified using specific primers for P. aeruginosa 16S rDNA. Ciprofloxacin minimum inhibitory concentrations (MIC) were estimated using the agar dilution assay. DNA sequences of the quinolone resistance-determining regions of gyrA and parC were determined for detecting the mutations found in these genes and the relations among the isolates by constructing phylogenetic trees. The results revealed that only 43 (82.7%) of isolates were P. aeruginosa, of which 31 (72.06%) were resistant to different concentrations of ciprofloxacin, ranging between 4 and >32 µg/ml. Twenty six isolates were selected for sequencing, including sensitive, intermediately resistant, and highly resistant to ciprofloxacin. The ciprofloxacin sensitive isolates did not exert any amino acid alterations in gyrA or parC genes; however, a single intermediately resistant isolate had a single mutation at each gene. Of the total resistant isolates (20), 6 isolates had no mutations at different MIC levels, While 14 isolates had Thr-83-Ile substitution in gyrA and Ser-87-Leu substitution in parC, only five isolates had a second mutation, namely Asp-87-Asn, in gyrA. The phylogenetic analysis of the studied groups showed divergence from the P. aeruginosa PAO1 and PAO1OR reference strains due to increased mutations and polymorphisms in studied isolates. In conclusion, P. aeruginosa occurrence was increased in burn infections and the fluoroquinolones in current use are not as effective as before; the main resistance mechanism in local clinical isolates of P. aeruginosa is mutations, where the main target of fluoroquinolones is gyrA gene.
Select 30 isolate from Bacillus to detect the ability to produce pullulanase enzyme in liquid and solid state fermentation, and use the isolate Bacillus licheniformis (Bs18) because the highest production of enzyme, the optimum condition for the production of enzyme by liquid state fermentation (LSF) in growen with: media contains starch + pullulan as a carbon source, peptone as a nitrogen source, inoculums size 2 ml, and incubated at 40 C° with pH 7 for 48 hrs. In addition pullulanase production by solid state fermentation (SSF) was investigated using isolated Bacillus licheniformis (Bs18). Optimization of process parameters were carried out ,the optimum solid substrate , Temperature , pH , incubation period , inoculation size , hydrat
... Show MoreIn this work, microbubble dispersed air flotation technique was applied for cadmium ions removal from wastewater aqueous solution. Experiments parameters such as pH (3, 4, 5, and 6), initial Cd(II) ions concentration (40, 80, and 120 mg/l) contact time( 2, 5, 10 , 15, and 20min), and surfactant (10, 20and 40mg/l) were studied in order to optimize the best conditions .The experimental results indicate that microbubbles were quite effective in removing cadmium ions and the anionic surfactant SDS was found to be more efficient than cationic CTAB in flotation process. 92.3% maximum removal efficiency achieved through 15min at pH 5, SDS surfactant concentration 20mg/l, flow rate250 cm3/min and at 40mg/l Cd(II) ions initial co
... Show MoreThis paper calculated the Duration Magnitude (MD) equation using data from the Iraqi Meteorological Organization and seismology (IMOS). It is an empirically determined equation and expressed as:
The epicentral distance and local geological conditions affect the duration of the coda. The data is obtained from 7 seismic stations in the network. The new proposed duration magnitude equation results from applying linear regression analysis to the data of a seismic signal duration with correlation coefficient R2=0.76; and a standard deviation value of 0.049. Station corrections indicated by Sc are also specified for the seismic stations that range from -0.024 to + 0.02.
Background: A great dental and biomedical interest had been paid to silver nanoparticles because of their antimicrobial activity. Objective: To evaluate the antimicrobial and cytotoxic activity of a newly developed Nano-silver fluoride that was synthesized from moringa oleifera leaf extract against S. mutants. Material and method: The green synthesis method was used to prepare Nano-silver fluoride from moringa oleifera leaf extract. The minimum inhibitory concentration and the minimum bactericidal concentration were evaluated using brain heart infusion plates, while the cytotoxicity was evaluated by the hemolytic activity. Results: Nano-silver fluoride had a bactericidal and bacteriostatic effect (MIC was 60 ppm a
... Show MoreDate stones were used as precursor for the preparation of activated carbons by chemical
activation with ferric chloride and zinc chloride. The effects of operating conditions represented
by the activation time, activation temperature, and impregnation ratio on the yield and adsorption
capacity towards methylene blue (MB) of prepared activated carbon by ferric chloride activation
(FAC) and zinc chloride activation (ZAC) were studied. For FAC, an optimum conditions of 1.25
h activation time, 700 °C activation temperature, and 1.5 impregnation ratio gave 185.15 mg/g
MB uptake and 47.08 % yield, while for ZAC, 240.77 mg/g MB uptake and 40.46 % yield were
obtained at the optimum conditions of 1.25 h activation time, 500
The removal of direct blue 71 dye from a prepared wastewater was studied employing batch electrocoagulation (EC) cell. The electrodes of aluminum were used. The influence of process variables which include initial pH (2.0-12.0), wastewater conductivity (0.8 -12.57) mS/cm , initial dye concentration (30 -210) mg/L, electrolysis time (3-12) min, current density (10-50) mA/cm2 were studied in order to maximize the color removal from wastewater. Experimental results showed that the color removal yield increases with increasing pH until pH 6.0 after that it decreased with increasing pH. The color removal increased with increasing current density, wastewater conductivity, electrolysis time, and decreased with increasing the concen
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