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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
Sun Jun 01 2014
Journal Name
2014 International Conference On Computer And Information Sciences (iccoins)
Proposed conceptual model for E-service quality in Malaysian universities
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Publication Date
Fri Jul 01 2016
Journal Name
Ira International Journal Of Education And Multidisciplinary Studies (issn 2455–2526)
Inappropriateness in Iraqi EFL Learners’ E-mail Requests to Professor
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<div><p><em>This study investigates the use of the speech act of request by </em><em>Iraqi EFL (English as a foreign language) learners </em><em>in student-professor e-mail communication. It aims to examine request strategies and internal modifications in academic requests in e-mail. There has been little investigation of the issue of an academic request made by Arab EFL learners to a higher status person via an authentic data. Thus, this study intends to provide more investigation of the strategies and internal modifiers that are produced by Iraqi EFL learners when they interact with their professors via e-mail. However, this study adapts the CCSARP (cross-cultural speech act realization pr

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Publication Date
Tue May 01 2018
Journal Name
Journal Of Engineering
Power System Stabilizer PSS4B Model for Iraqi National Grid using PSS/E Software
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To damp the low-frequency oscillations which occurred due to the disturbances in the electrical power system, the generators are equipped with Power System Stabilizer (PSS) that provide supplementary feedback stabilizing signals. The low-frequency oscillations in power system are classified as local mode oscillations, intra-area mode oscillation, and interarea mode oscillations. Double input multiband Power system stabilizers (PSSs) were used to damp out low-frequency oscillations in power system. Among dual-input PSSs, PSS4B offers superior transient performance. Power system simulator for engineering (PSS/E) software was adopted to test and evaluate the dynamic performance of PSS4B model on Iraqi national grid. The res

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Publication Date
Wed Sep 15 2021
Journal Name
Al-academy
The impact of e-learning on the cognitive level in the Corona crisis: أسماء غازي عبد
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E-learning is a necessity imposed by the Corona pandemic, which has disrupted various educational institutions in the world, but some of these institutions have not been affected and education has continued with them, due to their flexible educational system that was able to employ technology in the continuity of the educational process in the so-called e-learning, because It has characteristics that make it the most suitable alternative to avoid the consequences of the Corona pandemic and its damage to the educational process, as e-learning is one of the modern methods that contribute to enhancing the effectiveness of the learner, and enabling him to assume greater responsibility compared to traditional education, so the learner becomes

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Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
Vitamin E Level In Friedreich’s Ataxic Phenotype Patients In Four Major Hospitals In Baghdad
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Background: Friedreich ataxia (FRDA) is the most common form of inherited ataxia, comprising one-half of all hereditary ataxias with a carrier rate between 1 in 60 to 1 in 90 and with a disease prevalence of 1 per 29,000. It can occur in two forms the classic form or in association with a vitamin E dependent ataxia. The precise role of Vitamin E in the nervous system is unknown; An Oxidative attack is suspected to play a role in Ataxia with Vitamin E deficiency, as well as in Friedreich ataxia. Vitamin E is the major free-radical-trapping antioxidant.

Objective: Theobjectives of the study is to asses vitamin E level in patients with Friedreichs ataxia phenotype in Iraqi patients.

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of The College Of Languages (jcl)
The Iraqi Learners' Production Of rp Clipped Vowel
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Within connected speech, RP speakers tend to shorten stressed long vowels end diphthongs in pre. Forties consonants in the same syllable on the basis of complementary Distribution, i.e., the phonological environment decides the influence of the forties plosives and fricatives, as far as they are in find position preceded by stressed long vowels and diphthongs, or particular voiced consonants plus vowels. The Iraqi learners, then, face.

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Development A Method For Production Of Carbon Nanotubes
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In this work chemical vapor deposition method (CVD) for the production of carbon nanotubes (CNTs) have been improved by the addition of S. Steel mesh container (SSMC) inside which the catalyst (Fe/Al2O3) was placed. Scanning electron microscopy (SEM) investigation method used to study nanotubes produced, showed that high yield of two types of (CNTs) obtained, single wall carbon nanotube (SWCNTs) with diameter and length of less than 50nm and several micrometers respectively and nanocoil tubes with a diameter and length of less than 100nm and several micrometers respectively. The chemical analysis of (CNTs) reveals that the main component is carbon (94%) and a little amount of Al (0.32%), Fe (2.22%) the reminder is oxygen. It was also fou

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Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Bio-production of Ethanol in Packed Bio reactor
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A lab-scale packed Bio film reactor was used for ethanol production by fermentation of sugar solution using a local
isolated yeast saccharomyces cerevisia and glutaraldelryde on gelating as a covalent bounding agent. In this study four
types of packing in the reactor were used. They are; polypropylene mesh, glass rashig rings, ceramic rashig rings and
glass beads. Glucose solutions were used as substrate with four concentrations; (5, I 0, I 5, 20 g/l). Results show that the
ethanol productivity was increase with increasing sugar concentration. Also it was found that polypropylene mesh
packing give the highest productivity while glass beads gives the lowest productivity. The experiments were conducted at
three temperatur

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Publication Date
Sun Jan 01 2023
Journal Name
Aip Conference Proceedings
Manufacturing electrolysis cell for hydrogen production
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Publication Date
Fri Nov 18 2022
Journal Name
International Journal Of Nanoscience
Plasma Production and Applications: A Review
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Large amounts of plasma, the universe’s fourth most common kind of stuff, may be found across our galaxy and other galaxies. There are four types of matter in the cosmos, and plasma is the most common. By heating the compressed air or inert gases to create negatively and positively charged particles known as ions, electrically neutral particles in their natural state are formed. Many scientists are currently focusing their efforts on the development of artificial plasma and the possible advantages it may have for humankind in the near future. In the literature, there is a scarcity of information regarding plasma applications. It’s the goal of this page to describe particular methods for creating and using plasma, which may be us

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