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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
Sat Jan 01 2022
Journal Name
International Journal Of Hydrogen Energy
Optimisation of operating parameters on the performance characteristics of a free piston engine linear generator fuelled by CNG–H2 blends using the response surface methodology (RSM)
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The free piston engine linear generator (FPELG) is a simple engine structure with few components, making it a promising power generation system. However, because the engine works without a crankshaft, the handling of the piston motion control (PMC) is the main challenge influencing the stability and performance of FPELGs. In this article, the optimal operating parameters of FPELG for maximising engine performance and reducing exhaust gas emissions were studied. Moreover, the influence of adding hydrogen (H2) to compressed natural gas (CNG) fuel on FPELG performance was investigated. The influence of operating parameters on in-cylinder pressure was also analysed. The single-piston FPELG fuelled by CNG blended with H2 was used to run the expe

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Publication Date
Tue Jan 01 2019
Journal Name
Journal Of Global Pharma Technology
A morphological study and a new species registration of genus Xerophloea Germa, 1839 sp.nov. From sub-family Ledrinae Fairmai, 1855 of the leafhopper (Hemiptera: Cicadellidae) in Iraq
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Publication Date
Thu Feb 28 2019
Journal Name
The Open Rheumatology Journal
The Value of Soluble Transferrin Receptor and Soluble Transferrin Receptor-ferritin Index in Discriminating Iron Deficiency Anaemia from Anaemia of Chronic Disease in Patients With Rheumatoid Arthritis
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Background:

Anaemia is a common extra-articular manifestation of rheumatoid arthritis (RA) where anaemia of chronic disease (ACD) and iron deficiency anaemia (IDA) are the two most frequent types. The distinction between these two types of anaemia has always been challenging requiring sophisticated techniques. Serum transferrin receptor (sTfR) a truncated soluble form of the transferrin receptor is one of the parameters that is influenced by the Iron content and supply to the erythrons and is not affected by inflammatory status and therefore the use of the sTfR/log ferritin (sTfR-F) index can be a reliable indicator of functional iron deficiency.

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Publication Date
Mon May 25 2026
Journal Name
Sciences Journal Of Physical Education
The effect of skill exercises according to the Keller model on attentional control and learning the shooting skills from stability and movement of basketball for female students
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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
The Extent to Which Future Skills are Employed During Teaching from the Viewpoint of Students of Islamic Studies and their Relationship to Students' Attitude towards Future Profession
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The research aims to identify the relationship between employing future skills during teaching from the viewpoint of students of Islamic studies at the Northern Border University, as well as their attitudes towards future professions. The researcher employed the correlational descriptive approach. The tools were a questionnaire for employing future skills, and a scale for the attitude towards the future profession. The two research tools were applied to a random sample of (242) male and female students from the department of Islamic Studies, College of Education and Arts. The findings showed that the total level of employing future skills and their three axes during teaching was average. It was also found that the attitude towards future

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Publication Date
Wed Aug 31 2022
Journal Name
Al-kindy College Medical Journal
Antimicrobial Activity of Lepidium Sativum against Multi drug resistant and sensitive Pseudomonas aeruginosa from clinical isolates, Khartoum State, Sudan: Lepidium Sativum against Clinical isolates of Pseudomonas aeruginosa
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Background: L. sativum, are traditionally used for the treatment of various diseases and thought to have medicinal value. Isolates from many part of the world is now multidrug resistant. Therefore, there is an urgent need to look for and test an alternative herbal drug.

Objective: The present study aimed to evaluate the antibacterial activity of L. Sativum seed extract against multi drug resistant (MDR) and sensitive Pseudomonas aeruginosa clinical isolates.

Subjects and Methods: An ethanolic and aqueous stock extracts were prepared from L.  sativum seed plant then serial dilutions were prepared and the obtained concentrations (50, 25, 12.5 and 6.2 mg/ml) were tested against 30 multidrug-resistan

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Publication Date
Thu Dec 31 2020
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
ASTUDYON THERECORDOF EVALUATINGTHE SUPPLIERSACCORDING TO THE CONCEPT OF QUALITY AND BENEFITING FROM IT IN PRACTICE IN AL-FURAT STATE COMPANY AND FINDING POSSIBLE PROPOSALS FOR ITS DEVELOPMENT: ASTUDYON THERECORDOF EVALUATINGTHE SUPPLIERSACCORDING TO THE CONCEPT OF QUALITY AND BENEFITING FROM IT IN PRACTICE IN AL-FURAT STATE COMPANY AND FINDING POSSIBLE PROPOSALS FOR ITS DEVELOPMENT
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Success in selecting the best among the sources of supply is one of the most important factors in the efficiency of the procurement activity in the company, because the proper selection of the source of the supply significantly affect the achievement of what is desired by the factors of quality, quantity, price and service, and the ability of the competent supplier to meet everything associated with this Factors of commitments, hereby supporting the procurement function's efforts to fully discharge its responsibilities, and in view of adopting of Al-Furat company quality management system by applying the standards of ISO (9001: 2015) and purpose of getting the on-demand benefits from the application of international standards reg

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Publication Date
Mon Dec 20 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
STUDY THE PHYSICAL AND CHEMICAL PROPERTIES AND DETERMINATION THE CYTOTOXICITY OF KOJIC ACID PRODUCED FROM THE LOCAL ISOLATE ASPERGILLUS FLAVUS WJF81 AND THEIR EFFECTS ON CONSUMER HEALTH.: STUDY THE PHYSICAL AND CHEMICAL PROPERTIES AND DETERMINATION THE CYTOTOXICITY OF KOJIC ACID PRODUCED FROM THE LOCAL ISOLATE ASPERGILLUS FLAVUS WJF81 AND THEIR EFFECTS ON CONSUMER HEALTH.
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Steps were taken to obtain the Kojic acid crystals from local fungal isolation A. flavus WJF81 by separating the fermentation products from the fungus mycelium from the production plant at the centrifuge at a speed of 5000 cycles for 10 minutes. The extraction was followed by ethyl acetate then supernatant concentrate by using rotary evaporator, and dried with heat oven 37ºC. Long, yellowish, pristine acid crystals were obtained that examined the optical microscope with a magnification force of 10x and 40x. The melting point of kojic acid was determined between 152.9-153.5 °C Results of the diagnosis of Kojic acid by applying High pressure liquid chromatography HPLC technique showed that the acid was at one peak, which was close to the

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Publication Date
Mon Jan 29 2024
Journal Name
Eximia
The cognitive and educational importance of the academic teacher for developing the applied skills of third-stage female students in the subject of teaching methods from their point of view
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The research aimed to prepare a measure of the importance of enlightenment, academic education, and applied skills for third-stage female students, including teaching methods from their point of view/College of Education and Sports Sciences/University of Baghdad/Al-Jadriyah. The researchers used descriptive description in the comprehensive research procedures, an appropriate methodology in achieving the research objectives, sufficient for interpretations, how important is the academic teacher’s knowledge of teaching methods for student learning, what are the roles that the learners have acquired from the academic teacher. The scale of importance and horror consists of 15 items. The research population includes female students of t

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Publication Date
Mon May 25 2026
Journal Name
Sciences Journal Of Physical Education
Perceived organizational support and its relationship to the cognitive competence of the Iraqi National Olympic Committee from the point of view of members of the Olympic sports federations in Iraq
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