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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 Jan 01 2018
Journal Name
World Journal Of Dentistry
Obturation of Lateral Canals by a New Reciprocating Spreader and a Conventional Finger Spreader by Lateral Condensation Technique: in vitro Comparative Study
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Publication Date
Wed Jun 29 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Effect of adding the Flavonoids from Zizypus spina-christi leaves in redox indicators of the fat extracted from Cows, Sheeps bones and storage on defferent temperature and periods.: Effect of adding the Flavonoids from Zizypus spina-christi leaves in redox indicators of the fat extracted from Cows, Sheeps bones and storage on defferent temperature and periods.
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Flavonoids were extracted from Zizyphus spina-christi leaves by Ethyl acetate after acid digested and used as antioxidant. The dried extract was added separately to each sample of fat extracted from hallow cow and sheep bones as follows: T1 cow fat, T2 control for cow fat, T3 sheep fat and T4 control for sheep fat (the control T2 and T4 reffered to samples without added antioxidant).
Samples were stored at -18, 5, 25 and 55 °C for 28 days. The storage trials were conducted at -18, 5 and 25 °C for 28 days for T1, T2, T3 and T4. The chemical indices examined initially and at the end of storage period. PVs was 1.46, 1.46, 1.8 and 1.8 meq/ Kg oil respectively, FFA values were 0.245, 0.245, 0.244 and 0.244% respectively and TBA va

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Publication Date
Thu Jun 27 2019
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FIRST RECORD OF SOLOSTAMENIDES PAUCITESTICULATUS KRITSKY & ÖKTENER, 2015 (MONOGENOIDEA, MICROCOTYLIDAE) FROM GILLS OF ABU MULLET PLANILIZA ABU (HECKEL, 1843) FROM EUPHRATES RIVER OF SAMAWA CITY, SOUTHERN IRAQ
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    A total of 54 abu mullet Planiliza abu (Heckel, 1843) were collected from two stations (north and south stations) along the Euphrates River near Samawa City, Al-Muthanna province and were examined during the period from October 2016 till September 2017 for parasites. Six out of 35 examined fishes from the north station (17.1%) and one out of 19 examined fishes (5.3%) from south station were infected with the microcotylid Solostamenides paucitesticulatus Kritsky & Öktener, 2015. The parasite was illustrated and described, and it is considered as a new record for the parasitic fauna of fishes of Iraq.

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Publication Date
Mon Mar 13 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of Osseointegration of Dental Implants Prepared by Piezosurgery (Clinical Study)
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ABSTRACT Background: Piezosurgery device is a system developed recently to overcome the limitation of the traditional surgical technique in implant site preparation, which use the principle of ultrasonic microvibrations to create precise & selective cut in bone in harmony with the surrounding tissues. The aim of this study was to evaluate the outcomes of implants inserted by ultrasonic implant site preparation protocol (UISP) using piezosurgery device, regarding the survival rate, stability and other related factors, at 16 weeks postoperative follow up period. Materials and Methods: A total of (24) patients, (6) males and (18) females, aged between (19-51) years old, contributed in this study receiving a total of (42) implants, all of these

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Publication Date
Tue May 26 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Expression of RANKL by dental cells during eruption of mice teeth
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Background : In order for a tooth to erupt, two obvious requirements are needed. First, there has to be alveolar bone resorption of the bone overlying the crown of the tooth such that an eruption pathway is formed. Second, resorption of bony crypt and apposition of new one, third, there has to be a biological process that will result in the tooth moving through this eruption pathway.The amniotic sac contains a considerable quantity of stem cells. These amniotic stem cells are multipotent and able to differentiate into various tissues, which may be useful for human application. Receptor activator of nuclear factor kappa B ligand (RANKL) is concentrated on bone biology, more specifically bone metabolism. RANKL plays a vital role in osteoclast

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Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Development of East Baghdad Oil Field By Clusters of Horizontal Wells
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There are varieties of reasons lead for drilling horizontal wells rather than verticals. Increasing the recovery of oil, especially from thin or tight reservoir permeability is the most important parameter.

East Baghdad oil field considered as a giant field with approximately more than 1billion barrel of a proved reserves accompanying recently to low production rate problems in many of the existing wells.

   It is important to say that presence of of  horizontal wells in East Baghdad field especially by converting some of already drilled wells by re-entry drilling horizontal sections may provide one of best solutions for the primary development stage in East Baghdad field which may be followed by drilling n

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of Cosmetics, Dermatological Sciences And Applications
Treatment of Kaposi’s Sarcoma by Combination of Zinc Sulfate and Propranolol
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Publication Date
Tue May 16 2023
Journal Name
Journal Of Engineering
Improvement of Resistance Spot Welding by Surfaces Treatment of AA1050 Sheets
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Resistance spot welding (RSW) aluminum alloys has a major problem of inconsistent quality from weld to weld, because of the problems of the non-uniform oxide layer. The high resistivity of the oxide causes strong heat released which influence significantly on the electrode lifetime and the weld quality. Much effort has been devoted experimentally to the study of the sheet surface characteristics for as-received sheet and surface pretreatment sheet by pickling in NaOH and glassblasted with three thicknesses (0.6, 1.0, and 1.5 mm) of AA1050. Three different welding process parameters energy setup as a low, medium, and high were carried. Tensile-shear strength tests were performed to indicate the weld quality. Moreover, microhardness tests,

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Publication Date
Sun Jun 06 2010
Journal Name
Baghdad Science Journal
Study of pollution by heavy elements in some parts of Baghdad
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The objective of the present work is to measuring the concentration of heavy elements (Pb, Cd, Zn, As) in Baghdad's soil city and indication to the probable sources of pollution as well as comparing the concentration of heavy elements with local and international ranges. The Sampling and analyzing conducted in the present work included ( 15 ) Samples from Baghdad city ( three samples for each location ).The rates of heavy elements in soil samples were as following:. Pb ( 67.5 ) ppm, Cd ( 4.11 ) ppm , Zn ( 77.9 ) ppm , As ( 4.64 ) ppm. According to the results, we find increasing in the concentrations of the heavy elements ( Pb, Cd, Zn ) in soils and decreasing in ( As ).We conclude that the main reason behind the in

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Publication Date
Sat Dec 24 2022
Journal Name
Research Journal Of Pharmacy And Technology
Biological Study of protease produced by clinical isolates of Staphylococcus aureus
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The bacterial isolates were obtained from Al-Kindi Hospital were diagnosed by the Vitek-2 system and re confirm by 16srRNA gene as S. aurous, the results were shown 20 isolates (66.7%) out of 30 isolates were positive to protease production. All bacterial isolates (100%) were sensitive to Gentamicin and Levofloxacin. but resistant (100%) to aztreonam. The best temperature for enzyme production from bacteria was 37 °C, and the best pH for enzyme production was 7. Partial purification of the bacterial enzyme (protease) was carried out using short steps included ammonium sulfate 65% saturation, ion exchange using DEAE- cellulose column and then applied on gel filtration chromatography using Sephadex G-200 column. The enzymatic activit

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