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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
Wed Jan 01 2014
Journal Name
Infection And Drug Resistance
Virulence and antimicrobial resistance of Escherichia coli isolated from Tigris River and children diarrhea
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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Sensitivity of Bacteria Escherichia coli Iisolated from Urinary Tract Infection toward Ciprofloxacin and Lomefloxacin.
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   Four hundred and fifty urine samples were collected from patients suffering from urinary tract infection from the General Azadi hospital in Kurkuk province ,during the period of october 2007 till march 2008 .       Results of bacteriological culture revealed that (168) out of (450) studied samples (37.3%) gave positive culture using blood agar and macConkey agar ; different species of bacterial isolates were detected using morphological and biochemical tests ,from these isolates the highest percentage of the isolates were from Escherichia coli when it was (100) isolates out of (190) isolate  (52.63%)  .  one hundred isolates were distributed between (77) from females and (23) from

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Production of fibrinolytic protease from various fungal isolates and species 2.Determination of optimum conditions for enzyme production from Pleurotus ostreatus
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The optimum conditions for production of fibrinolytic protease from an edible mushroom Pleurotus ostreatus grown on the solid medium , Sus medium, composed of Sus wastes (produced from extracted medicinal plant Glycyrrhiza glabra) were determined. Addition of 5% of Soya bean seeds meal in Sus medium recorded a maximum fibrinolytic protease activity resulting in 7.7 units / ml. The optimum moisture content of Sus medium supplemented with 5% Soya bean seeds meal was 60% resulting in 7.2 units / ml.Pleurotus ostreatus produced a maximum fibrinolytic protease activity when the spawn rate,pH of medium and incubation temperature were 2,6 and 30°C, respectively. The maximum fibrinolytic protease activity was 7.6 units / ml when incubat

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Publication Date
Mon Dec 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Bioethanol (Biofuel) Production from Low Grade Dates
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Bioethanol production from sugar fermentation is one of the most sustainable alternatives to substitute fossil fuel. production of bioethanol from low grade dates which are rich of sugars. An available sugar from a second grade dates (reduction sugar) was 90g/l in this study. Sugar can be served as essential carbon sources for yeast growth in aerobic condition and can also be converted to bioethanol in anaerobic condition. The effect of various parameters on bioethanol production, fermentation time, pH-values, inoculum size and initial sugar concentration were varied in order to determine the optimal of bioethanol production. The highest bioethanol yield was 33g/l which was obtained with sugar concentration 90 g/l, inocu

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Publication Date
Thu Jun 30 2011
Journal Name
Al-kindy College Medical Journal
Local Expression of MMP-7 in Oral Cancer
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Background: Squamous cell carcinoma of the oral
cavity (OSCC) is a highly invasive neoplasm. Many
MMPs play role in human cancer invasion and
metastases.
Aim: Estimating The MMp-7 expression level in
HPV-16 positive and HPV-16 negative OSCC
paraffin embedded sections.
Method: Biopsies from thirty three patients with oral
squamous cell carcinoma (OSCC) were obtained and
investigated for the presence of HPV-16 RNA with
the application of ISH and the MMP-7 expression
level using IHC .
Results: Expression level of MMP-7 found to be high
in OSCC sections 29 (87.8%) cases with no
significant difference in its expression level between
HPV-16 positive and HPV-16 negative OSCC cases
p= 1.00.
Conc

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Publication Date
Tue Jan 01 2013
Journal Name
Bio-genetics Journal
Measuring the toxicity of Heat Stable Enterotoxin (a) produced by Enterotoxigenic Escherichia coli on human blood lymphocyte from normal and colorectal cancer patients in vitro
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This research was conducted to measure the safety of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli, through studying its toxic effect on human blood lymphocyte, since it showed a promising effect in reducing the proliferation of colorectal cancer cells. the cytogenetic effects of (STa) by using five different concentrations (100, 200, 400, 800 and 1600μg/ml) in comparison with negative (PBS, Phosphate buffer saline) and positive (MMC, Mitomycin C) at concentration of 5μg/ml, controls on human blood lymphocytes obtained from both (10) normal healthy persons and (20) colorectal cancer patients was measured by employing the following parameters: mitotic index, blast index, chromosomal aberrations and micronucle

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
ESTIMATION THE 7 AND 28- DAY NORMAL COMPRESSIVE STRENGTH BY ACCELERATED TEST METHODS IN CONCRETE
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Curing of concrete is the maintenance of a satisfactory moisture content and temperature for a
period of time immediately following placing so the desired properties are developed. Accelerated
curing is advantages where early strength gain in concrete is important. The expose of concrete
specimens to the accelerated curing conditions which permit the specimens to develop a significant
portion of their ultimate strength within a period of time (1-2 days), depends on the method of the
curing cycle.Three accelerated curing test methods are adopted in this study. These are warm water,
autogenous and proposed test methods. The results of this study has shown good correlation
between the accelerated strength especially for

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Publication Date
Tue Jan 15 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
INHIBITORY EFFECT OF THYMOL EXTRACTS ON ENTEROTOXINS PRODUCTION BY Staphylococcus aureus.: INHIBITORY EFFECT OF THYMOL EXTRACTS ON ENTEROTOXINS PRODUCTION BY Staphylococcus aureus.
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One hundred and eighty five urine samples were collected eight isolates (4.3%) were obtained and diagnosed as Staphylococcus aureus. Among 8 isolates, 5 (62.5%) S. aureus isolates were found to be enterotoxigenic, most of isolates produced at least two types of Staphylococcal enterotoxins (SEs). The production of enterotoxins in the presence or absence of Thymol extracts (aqueous and alcoholic) were estimated using a reversed passive latex agglutination (SET-RPLA) kit. The extracts reduced enterotoxin production compared with the control. Enterotoxin inhibition was observed for enterotoxin C production at minimal inhibitory concentrations (MIC) at 400 µg/ml, whereas production of enterotoxins A, B, and

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Publication Date
Mon Mar 29 2021
Journal Name
Journal Of Engineering
Kinetic Studies of Biodiesel Production from Jatropha curcas Oil
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The world is confronted with the twin crisis of fossil fuel depletion and environmental degradation caused by fossil fuel usage. Biodiesel produced from renewable feedstocks such as Jatropha seed oil or animal fats by transesterification offers a solution. Although biodiesel has been produced from various vegetable oils such as Jatropha seed oil, the reaction kinetics studies are very few in literature, hence the need for this study. Jatropha curcas seed oil was extracted and analyzed to determine its free fatty acid and fatty acid composition. The oil was transesterified with methanol at a molar ratio of methanol to oil 8:1, using 1% sodium hydroxide catalyst, at different temperature

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Publication Date
Fri Mar 30 2012
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Production and Evaluation of Biodiesel from Sheep Fats Waste
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Animal fats are a good, promising and ethical alternative source for biodiesel production, but they need more complex treatments than vegetable oils. Iraqi butchery plants waste fats (sheep fat) which are suggested as feedstock to produce biodiesel. This type of fat contains a large quantity of free fatty acids (FFAs) (acid number 49.13 mg KOH/g of fat). The direct transesterification of such fats produce high amount of soap instead of desired biodiesel, so a pre-treatment step (to reduce FFAs) is necessary before transesterification. This step was done by esterification of the free fatty acids in the fat by adding ethanol and using 1% acid catalyst (H2SO4) for 30 minutes. The results showed that the acid number of sheep fat after pre-tr

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