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Production of 7-methylxanthine from Theobromine by Metabolically Engineered E. coli
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In this work, a novel biocatalytic process for the production of 7-methylxanthines from theobromine, an economic feedstock has been developed. Bench scale production of 7-methlxanthine has been demonstrated. The biocatalytic process used in this work operates at 30 OC and atmospheric pressure, and is environmentally friendly. The biocatalyst was E. coli BL21(DE3) engineered with ndmB/D genes combinations. These modifications enabled specific N7- demethylation of theobromine to 7-methylxanthine. This production process consists of uniform fermentation conditions with a specific metabolically engineered strain, uniform induction of specific enzymes for 7-methylxanthine production, uniform recovery and preparation of biocatalyst for reaction and uniform recovery of pure 7-methylxanthine.

   Many E. coli BL21(DE3) strains metabolically engineered with single and/or multiple ndmB/D genes were tested for catalytic activity, and the best strains which had the higher activity were chosen to carry out the N-demethylation reaction of theobromine. Strain pBD2dDB had the highest activity for the production of 7-methylxanthine from theobromine. That strain was used to find the optimum amount of cells required to achieve complete conversion of theobromine to 7-methylxanthine within two hours. It was found that the optimum concentration of pBD2dDB strain to achieve 100% conversion of 0.5 mM theobromine to 7-methylxanthine was 5 mg/mL. The cell growth of pBD2dDB strain was studied using two different growth media, (Luria-Bertani Broth and Super Broth). Super broth was found to be the best medium to produce the highest amount of cell paste (1.5 g). Subsequently, the process was scaled up in which 2 L reaction volume was used to produce 7-methylxanthine (100% conversion) from 0.5 mM theobromine catalyzed by pBD2dDB strain. The reactions was carried out at 30 oC and 250 rpm shaker speed, and the reaction medium was 50 mM potassium phosphate buffer (pH=7). 7-methylxanthines was separated by preparative chromatography with high recovery, and the product solution was collected, purified by drying at 120-140 oC for 4 hours and, recovered (127 mg). Purity of the isolated 7-methylxanthine was comparable to authentic standards with no contaminant peaks, as observed by HPLC, LC-MS, and NMR. 

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Publication Date
Thu Jul 01 2010
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FOUR NEW SPECIES OF THRIPS (THYSANOPTERA: THRIPIDAE) FROM MIDDLE OF IRAQ
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Four new species of Thrips (Thripidae) Chirothrips imperatus sp. nov.; Frankliniella megacephala sp. nov.; Retithrips bagdadensis sp. nov; Taeniothrips tigridis sp. Nov.; from middle of Iraq, are described and illustrated with their hosts.

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Publication Date
Thu Mar 07 2013
Journal Name
International Journal Of Pharma Sciences
Separation and Purification of Hemolysin from Local Isolate of Serratia marcescens
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Twenty isolates of Serratia marcescens were isolated from inflammation of the urinary tract (UTI)., These isolates were found to produce hemolysin as indicated by blood agar plates in which the hemolysis of red blood cell indicate a positive result. Isolates were selected according to their hemolysis activity by measuring absorbance of hemoglobin at 405 nm that released from red blood cell. Hemolysin was completely purified using 50-75% saturation of ammonium sulphate followed by ion exchange chromatography with DEAE-cellulose then gel filtration chromatography by sepharose 4B. Accordingly molecular weight for the purified toxin was estimated as 45 KD.

Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Comparative study of hydatid cysts isolated from livers of different hosts
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Fifty three hydatid cysts were collected from different hosts, sheep, goats and cattle , from many slaughterhouse in Salahadin and Baghdad , while human's hydatid cysts samples were collected from Tikrit educational hospital and Tofiqe civilian hospital patients . The study included a biochemical comparison of some hydatid cyst fluid criteria such as, glucose, total protein, pH, glutamate pyrovate transaminase enzyme (GPT) , glutamate oxaloacetate transaminase enzyme (GOT) , acid phosphatase (ACP) , Alkaline Phosphatase (ALP) , and also studied protoscolices viability,the current study showed the differences in chemical composition of hydatid cyst fluids back to host type and parasite strain .

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Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Effect of chelating agents on removal of 137Cs from contaminated soil
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In the present research, the chemical washing method has been selected using three chelating agents: citric acid, acetic acid and Ethylene Diamine Tetraacetic Acid (EDTA) to remove 137Cs from two different contaminated soil samples were classified as fine and coarse grained. The factors that affecting removal efficiency such as type of soil, mixing ratio and molarity have been investigated. The results revealed that no correlation relation was found between removal efficiency and the studied factors. The results also showed that conventional chemical washing method was not effective in removing 137Cs and that there are further studies still need to achieve this objective.

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Publication Date
Thu Mar 26 2009
Journal Name
Iraq Journal For Science
Calculation of time Entry and Exit of satellites from Earth Shadow
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The tracking of satellites motion and their path around the earth is important things in the mechanical of satellites motion. Significant parameters for the determination of time entrance and existence of the satellite could be obtained from the shadow of the earth. In the present work the tracking and time determination for entry and exit from earth shadow have been studied. In the present work we built a software for tracking the motion of satellites in orbit around the earth and determine the change of both distance and speed as a function of time. The perturbations effect on the satellite has been neglected from the earth atmosphere drag and the earth gravity and other effects. The equation for calculating the shadow is solved using num

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Publication Date
Tue Jun 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Extraction of Iron from Aqueous Chloride Media in Presence of Aluminum
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The extraction of iron from aqueous chloride media in presence of aluminum was studied at different kinds of extractants(cyclohexanone, tributyl phosphate, diethyl ketone), different values of normality (pH of the feed solution), agitation time, agitation speed, operating temperature, phase ratio (O/A), iron concentration in the feed, and extractant concentration]. The stripping of iron from organic solutions was also studied at different values of normality (pH of the strip solution) and phase ratio (A/O). Atomic absorption spectrophotometer was used to measure the concentration of iron and aluminum in the aqueous phase throughout the experiments.The best values of extraction coefficient and stripping coefficient are obtained under the

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Publication Date
Sat Jun 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Recovery of Vanadium from Scale Residues of Oil-Fired Power Stations
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Publication Date
Tue Jan 01 2002
Journal Name
Annals Of Saudi Medicine
Treatment of viral warts by intralesional injection of zinc sulphate
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KA Sharquie, AA Al-Nuaimy, Annals of Saudi Medicine, 2002 - Cited by 48

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Publication Date
Sun Mar 04 2018
Journal Name
Baghdad Science Journal
Biodegradation of Anthracene Compound by Two Species of Filamentous Fungi
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Isolation and identification fungi of Emericella nidulans and Aspergillus flavus from a pinkish and yellowish artificial clay, by using potato dextrose agar (PDA). Results revealed that E. nidulans was the best for degrading anthracene (92.3%) with maximum biomass production (3.7gm/l), compared to A. flavus with the rate of degradation (89%) and biomass production of (1.2gm/l), when methylene blue was used as redox indicator after incubating in a shaker incubator 120rpm at 30Co for 8days. Results indicated that E. nidulans has a high ability of anthracene degradation with the rate of (84%), while A. flavus showed the lower level with (77%) by using HPLC.

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Publication Date
Tue Dec 21 2021
Journal Name
Physical Chemistry Research
Photocatalytic and optical performances of CeO2 by substitution of titanium
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In this contribution, density functional theory-based calculations have been carried out to assess the electronic, photocatalytic and optical properties of Ce1-xTixO2 system. Ti incorporation leads to a decrease of Ce 4f states and enhancement of Ti 3d states in the bottom of conduction band. Furthermore, it was found that doping ceria with Ti-like transition metals could evidently shift the absorption of pure CeO2 towards higher wavelength range. These findings can provide some new insights for designing CeO2-based photocatalysts with high photocatalytic performance. To the best of our knowledge, this investigation calculates Mullikan’s charge transfer of Ce1-xTixO2 system for the first time. Charge transfer reveals an ionic bond between

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