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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
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
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 May 16 2023
Journal Name
Journal Of Engineering
Estimation of Flexural Strength of Plain Concrete from Ultrasonic Pulse Velocity
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The aim of this study is to propose mathematical expressions for estimation of the flexural strength of plain concrete members from ultrasonic pulse velocity (UPV) measurements. More than two hundred
pieces of precast concrete kerb units were subjected to a scheduled test program. The tests were divided into two categories; non-destructive ultrasonic and bending or rupture tests. For each precast unit, direct and indirect (surface) ultrasonic pulses were subjected to the concrete media to measure their travel velocities. The results of the tests were mointered in two graphs so that two mathematical relationships can be drawn. Direct pulse velocity versus the flexural strength was given in the first relationship while the second equati

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Publication Date
Wed Oct 02 2013
Journal Name
Journal Of Biology, Agriculture And Healthcare
The Prevalence of Aerobic Bacteria Isolated from Horses Fecal Samples
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Dietary components and changes cause shifts in the gastrointestinal microbial ecology that can play a role in animal health and a wide range of diseases. However, most information about the microbial populations in the gut of horses has not been quantitative. The objective of this study was to characterize the fecal bacterial and its prevalence in healthy horses and diarrheal one in a period from September 2010 to July 2013. Out of 100 Fecal samples of horses (from farms in Al-furusyia club) in Baghdad were examined for microbial differentiation founded eighty percent of the fecal samples isolated from healthy horses. The most common pathogen found were Streptococcus spp. (33.7%), Escherichia coli (20.9%), , and Staphylococcus aureus (9.2

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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Evidence Supports The Formation Of Isoimides Derived From Pyromellitic Dianhydride
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Some new mono isoimides of asymmetrical pyromillitdiimide derived from pyromellitic dianhydride were synthesized and studied by their melting points, FTIR, and 1HNMR spectroscopy and CHN analysis (for some of them) and it was proved that the mechanism of the formation of these isoimides followed, the mechanism suggested by Cotter et al. by using N, N─-dicyclohexylcarbodiimide as dehydrating agent, in spite of the groups attached to the phenyl moiety as mentioned in literatures.

Publication Date
Sun Jun 06 2010
Journal Name
Baghdad Science Journal
Synthesis of Some Heterocyclic Compounds derived from 2-mercapto pyrimidine
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In this work 2-hydrazino pyrimidine (1) was prepared from 2-mercapto pyrimidine with hydrazine hydrate. Treatment of (1) with active methylene compounds gave 2-(3,5-dimethyl -1 H – Pyrazole-1-yl) pyrimidine , whereas the reaction of (1) with carboxylic anhydride namely maleic anhydride or 1,2,3,6-tetra hydro phthalic anhydride yielded 1-Pyrimidine-2-yl-1,2-dihydro pyridazine-3,6-dione (3) and 2 – Pyrimidin -2-yl -2,3,4 a ,5,8 a – hexahydro phthalazine 1,4 – dione (4) . Reaction of (1) with phenyl isothiocyanate and ethyl chloro acetate afforded 3-Phenyl-1,3-thiazolidine-2,4-dione-2( pyrimidine -2- yl hydrazone (6) Azomethine (7-10) were prepared through condensation of (1) with aromatic aldehydes or ketones, then comp

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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Purification and characterization of L-asparaginase produced from Bacillus sp.
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The objective of this study was to isolate and identify the asparaginase-producing bacteria, then purify and characterize the enzyme in order to investigate their properties in the future. Fifteen local bacterial isolates were isolated from various sites in the city of Baghdad, identified by conventional morphological and biochemical procedures, and confirmed using vitek 2 methods, and submitted to primary screening processes for asparaginase production. For secondary screening, eight isolates with the greatest yellow zone ability on a specific solid medium were chosen. Bacillus sp. was reported to have the highest enzyme production (7.5 U/mg proteins). After 24 hours of incubation, submerged fermentation yielded optimal conditi

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Publication Date
Sun May 05 2024
Journal Name
Review Of Clinical Pharmacology And Pharmacokinetics - International Edition
Isolation and characterization of a tetrahydroprotoberberine alkaloid from Crassula ovata
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The presence of alkaloids in Crassula ovata is a topic that is still unexplored, as there are no published studies on the matter. This study demonstrates the presence of an alkaloid compound (and its class) for the first time in Crassula ovata. The plant material was defatted with n-hexane, and a Soxhlet apparatus was used for the extraction process, while the acid-base method was used for the isolation of alkaloids from the chloroform fractions. The quaternary alkaloid was precipitated from the aqueous layer spontaneously, in high quantity. By using standard spectroscopic methods (including liquid chromatography - mass spectroscopy) we were able to clarify the structure of the precipi¬tated compound as a tetrahydroprotoberberine a

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Publication Date
Sat Jan 01 2011
Journal Name
سومر
unpublished cuneiform texts from daynisty of larse (2005-1763 B.C)
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After the fall of the Third Dynasty of Ur at the hands of the Elamites during the reign of its last ruler, King Ibi-Sin, the Amorites continued to flow more into Mesopotamia in the form of large migrations that established a number of contemporary and conflicting ruling dynasties that formed the Old Babylonian era. Among these dynasties was the Larsa dynasty, founded by King Nablanum in the city of Larsa. The fourth king who ruled in the Larsa dynasty, Gungunum, was one of the most powerful kings who stood up to the Isin dynasty, which had until that time enjoyed great political superiority in the country. The kings who ruled after him expanded their influence and controlled a number of cities, especially the cities of Nippur and Uruk, whic

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