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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 30 2013
Journal Name
Journal Of Madenat Alelem
Effect of Essential Oils Extracted from the Peels of Two Species of Citrus on Some Fungi
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This study investigated the effect of essential oils extracted from peel of Citrus limon and Citrus reticulata on two species of fungui: Penicillium expansum and Fusarium proliferatum and also effect of two fungicides: Hymexazol and Benomyl against this fungi. Results showed that the essential oils of C. limon inhibited the radial growth of P. expansum and F. proliferatum at concentration 4.5 and 5%, respectively. However, the essential oil of C. reticulate inhibited this growth at concentration 5.5 and 6%, respectively. Moreover, the two fungicides inhibited radial growth of this fungi. In conclusion, there is a positive relationship between the increasing of concentration and the percentage of inhibiting of radial growth of fungi.

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Publication Date
Sat Apr 01 2023
Journal Name
Journal Of Ecological Engineering
Dual Application of Al-Kheriat of Removal of Arsenic from Aqueous Solution and Acting as Rodenticide
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Arsenic is a prevalent and pervasive environmental contaminant with varied amounts in drinking water. Arsenic exposure causes cancer, cardiovascular, liver, nerve, and ophthalmic diseases. The current study aimed to find the best conditions for eliminating arsenic from simulated wastewater and their effect on biomarkers of hepatic in mice. Adsorption tests including pH, contact duration, Al-kheriat dosage, and arsenic concentrations were evaluated. Seventy-two healthy albino mice (male) were accidentally allocated into nine groups (n = 8), the first group was considered as healthy control, the second group (AL-Kheriat), and other groups received AL-Kheriat and arsenic 25, 50, 75, 100, 125, 150 and 175 mg/kg, respectively. Next 10 days, the

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Publication Date
Thu Nov 16 2023
Journal Name
International Journal Of Emerging Technologies In Learning (ijet)
The Importance of Using Metaverse Technology in Education from the Point of View of University Teachers
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The study aims to demonstrate the significance of metaverse technology across various disciplines, academic degrees, scientific fields, and academic titles. It also aims to assess the level of knowledge and understanding of university teachers (research sample) regarding metaverse technology. Hence, the descriptive research methodology was based on the method of statistical survey in the sample. It involved a set of organized scientific steps to deduce data from the reality of the statistical sample and its nature in order to achieve the objectives of the study. In this study, a questionnaire was used as a tool to collect data from a random sample of approximately 121 teachers and instructors from the University of Baghdad. This app

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Publication Date
Wed Jun 29 2022
Journal Name
College Of Islamic Sciences
The question of demand: definition, divisions, and examples from the controversy of the scholars of jurisprudence.
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research summary

Praise be to Allah، and prayers and peace be upon His Messenger and His chosen one، his family، companions and his family and his family.

After that، this is a study on the question of the claim، as one of the controversial questions that are the mainstay of debates، and I looked at it: the limit of the question of the claim، its importance، its impact، its aspects of corruption، its sections، and the representation of its sections of the fundamentalist controversy;

The research was according to the following plan:

Introduction، in which she mentioned: the importance of the research topic and the reason for its selection، its questions، its l

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Publication Date
Thu Oct 01 2015
Journal Name
International Journal Of Current Engineering And Technology
Synthesis of Gold Nanoparticle in the form of Paper Willow by Hot Chemical Reduction Method
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Abstract: Colloidal gold nanoparticles (ringworm Palm or in the form of paper willow) have been prepared from HAuCl4 containing aqueous solution by hot chemical reduction method. The colloidal gold nanoparticles were characterized by SEM, EDX, and UV-VIS absorption spectroscopy. It was found that the variation of reduction time from boiling point affects the size of the nanoparticles and also in chemical reduction approach the size of nanoparticles can be controlled by varying the amount of variation the volume of reductant material with respect to the volume of HAuCL4.

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of Engineering
Optimal Economic Design of Diversion Structures during Construction of a Dam by Particle Swarm Optimization
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Publication Date
Mon Jan 01 2018
Journal Name
International Journal Of Science And Research (ijsr)
Optimal Economic Design of Diversion Structures during Construction of a Dam by Particle Swarm Optimization
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Diverting river flow during construction of a main dam involves the construction of cofferdams, and tunnels, channels or other temporary passages. Diversion channels are commonly used in wide valleys where the high flow makes tunnels or culverts uneconomic. The diversion works must form part of the overall project design since it will have a major impact on its cost, as well as on the design, construction program and overall cost of the permanent works. Construction costs contain of excavation, lining of the channel, and construction of upstream and downstream cofferdams. The optimization model was applied to obtain optimalchannel cross section, height of upstream cofferdam, and height of downstream cofferdamwith minimum construction cost

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Publication Date
Sun Sep 30 2012
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Increasing of Oil Field Productivity by Implementation of Re-entry Horizontal Injection Well, Case study
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Water flooding is one of the most important methods used in enhanced production; it was a pioneer method in use, but the development of technology within the oil industry, takes this subject toward another form in the oil production and application in oil fields with all types of oils and oil reservoirs. Now days most of the injection wells directed from the vertical to re-entry of full horizontal wells in order to get full of horizontal wells advantages.
This paper describes the potential benefits for using of re-entry horizontal injection wells as well as combination of re –entry horizontal injection and production wells. Al Qurainat productive sector was selected for study, which is one of the four main productive sectors of Sout

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Publication Date
Wed Mar 30 2022
Journal Name
College Of Islamic Sciences
The adequacy of determining the direction of Qibla by modern methods in the Islamic jurisprudence
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    This Paper aims to know the modern approaches of determining the Qiblah and its ruling in Islamic Faqah, as well as to find out the required in the identity of the Qiblah or the eye, and the care of the advanced Jurists in this matter, and to present some of their sayings on the issue. we have followed the Descriptive analytical method of the aspects of the jurists ’difference in what is required when facing the qiblah either the eye or aspect, the approach of several demands branched out from each topic, which were answered in the theoretical framework of the research, and the research concluded with the most important results: The need to receive the eye of the qiblah for the worshiper who is close to it and it is no

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Publication Date
Fri May 01 2009
Journal Name
Atti Della “fondazione Giorgio Ronchi”
Study of synthesis of nanocrystalline CdS thin film in PVA matrix by chemical bath deposition
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SUMMARY. – Nanocrystalline thin fi lms of CdS are deposited on glass substrate by chemical bath deposited technique using polyvinyl alcohol (PVA) matrix solution. Crystallite size of the nanocrystalline films are determining from broading of X-ray diffraction lines and are found to vary from 0.33-0.52 nm, an increase of molarity the grain size decreases which turns increases the band gap. The band gap of nanocrystalline material is determined from the UV spectrograph. The absorption edge and absorption coefficient increases when the molarity increases and shifted towards the lower wavelength.

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