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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
Mon Mar 02 2015
Journal Name
Asian J. Res. Pharm. Sci.
Prevalence of Pathogenic Bacteria from Contaminated Yemeni Currency Notes in Taiz City
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ABSTRACT: Pathogenic bacteria responsible for the causation of many common diseases have been identified on currency notes. The present investigation was carried out on one hundred currency notes of all the denominations (50, 100, 250, 500 and 1000RY), obtained from different occupational mainly bus drivers, hawker street, vegetable vendor, restaurants and butchers and fish seller groups in Taiz city,Yemen. Identification and characterization revealed active participation of the following species of organisms in the ascending order of percentage as E. coli(50.28 %),Staphylococci aureus(14.04 %), Klebsiellaspp(4.39 %),proteus(4.39 %), salmonella(1.25 %), shigella(0.72 %), Coagulase negative staphylococcus(0.60 %), pseudomonas(0.50 %),

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Publication Date
Sun Oct 11 2026
Journal Name
Al–bahith Al–a'alami
THE ROLE OF WESTERN LEGISLATIONS AND LAWS IN PROTECTING CHILDREN FROM ADVERTISEMENT
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This study aims to identify the most important legislatures and legal frameworks pertaining to advertisement for children. It focuses on the western approach, which is characterized by the variety of its perspectives in presenting issues and in identifying problems. However, if studies show that there is a certain awareness about the advertisement impact on children, it is obvious that most of legislatures reject the laws restricting the broadcast advertising spots intended for children under 12 years of age, with the exception of the Swedish and the Canadian province of Quebec experiences, which opted for total ban on advertising spots broadcast messages targeting children.

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Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Ecological Engineering
Adsorption of Lead Ions from Aqueous Solutions onto Rice Husks, Continuous System
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Publication Date
Thu Dec 15 2022
Journal Name
Journal Of Juridical And Political Science
Civil Liability Arising from Children Abuse. A Comparative Study of American Law
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Researchers are interested in the issue of children abuse and they look for its cause in the past and present. Their interest is limited to identifying penal liability which is caused by children abuse away from focusing on civil liability. So, the study is going to clarify the parents' responsibility for children abuse rather than civil liability of the medic in case he wouldn’t notify the authorities about the case according to the American law rules and the attitude of Iraqi law rather than some judicial application of civil cases that were exposed to American judiciary concerning children abuse.

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Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Removal of-Copper Ions-from Aqueous Solution Using Liquid-Surfactant-Membrane Technique
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Extraction of copper (Cu) from aqueous solution utilizing Liquid Membrane technology (LM) is more effective than precipitation method that forms sludge and must be disposed of in landfills. In this work, we have formulated a liquid surfactant membrane (LSM) that uses kerosene oil as the main diluent of LSM to remove copper ions from the aqueous waste solution through di- (2-ethylhexyl) phosphoric acid - D2EHPA- as a carrier. This technique displays several advantages including one-stage extraction and stripping process, simple operation, low energy requirement, and. In this study, the LSM process was used to transport Cu (II) ions from the feed phase to the stripping phase, which was prepared, using H2SO4. For LSM p

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Publication Date
Wed Nov 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Two New Records of Coelioxys Latreille, 1809 (Hymenoptera: Apoidea: Megachilidae) from Iraq
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Abstract<p>Five <italic>Coelioxys</italic> Latreille, 1809 species previously recorded in Iraq; <italic>Coelioxys emargintus</italic> Förster, 1853 and <italic>Coelioxys brevis</italic> Eversmann, 1852 newly recorded species. A brief re-description of each is given, supported by photographs; as well as a provided for their global distribution.</p>
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Publication Date
Sun Jan 01 2012
Journal Name
Ibn Al- Haitham J. Fo R Pure & Appl. Sci
Multiple Mixing Ratios of Gamma Rays From Reaction Using a2-ratio Method
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The -multiple mixing ratios of γ-transitions from levels of populated in the are calculated in the present work by using the a2-ratio methods. We used the experimental coefficient (a2) for two γ-transitions from the same initial state, the statistical tensor, which is related to the a2-coefficient would be the same for the two transitions. This method was used in a previous work for pure transitions or which can be considered pure. In these cases the multiple mixing ratios for the second transition ( ) equal zero, but in our work we applied this method for mixed γ-transitions and then the multiple mixing ratio ( ) is known for one transition. Then we calculate the ( ) value and versareversa. The weight average of the -values calcu

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Publication Date
Fri Sep 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Sorption of Nitrate Salts from Wastewater without and with Modification Orange Peel
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This investigation deals with the use of orange peel (OP) waste as adsorbent for removal of nitrate (NO3) from simulated wastewater. Orange peel prepared in two conditions dried at 60C° (OPD) and burning at 500 °C (OPB). The effect of pH: 2-10, contact time: 30- 180 min, sorbent weight: 0.5- 3.0 g were considered. The optimal pH value for NO3 adsorption was found to be 2.0 for both adsorbents. The equilibrium data were analyzed using Langmuir and  Freundlich isotherm models. Freundlich model was found to fit the equilibrium data very well with high-correlation coefficient (R2). The adsorption kinetics was found to follow pseudo-second-order rate kinetic model, with a good correlation (R2

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Publication Date
Fri Jan 03 2020
Journal Name
Biochem. Cell.arch.
SPECTROSCOPIC, THERMODYNAMIC AND KINETIC STUDIES OF LIGAND COMPLEXES DERIVED FROM 2-AMINOTHIOPHENOL
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Publication Date
Thu Jan 01 2026
Journal Name
Iranian Journal Of Ichthyology
Synthesis and characteristic of new polyamides via schiff bases derived from ampicillin
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This study includes synthesis, characterization three series of the new derivatives via schiff bases for ampicillin which known as a high medicinal effectiveness. Series A include preparation schiff bases (A1-A6) by condensation of ampicillin with many substituted aldehyedes, while series B include preparation of six amines (B1-B6) is hydrazine hydrate derivatives by reaction schiff bases compounds which prepared in series A with hydrazine hydrate, then series C included for preparation of new six polymers C1-C6 by reaction of poly methyl methacrylate with amine compounds which prepared in series B. The synthesized polymers were identified by spectroscopic methods (FT-IR and 1 H-NMR) and measurement some of its physical characteristics.