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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
Tue Sep 01 2020
Journal Name
Baghdad Science Journal
Molecular Characterization of Plasmid-Mediated Non-O157 Verotoxigenic Escherichia coli Isolated from Infants and Children with Diarrhea
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A significant increase in the incidence of non-O157 verotoxigenic Escherichia coli (VTEC) infections have become a serious health issues, and this situation is worsening due to the dissemination of plasmid mediated multidrug-resistant microorganisms worldwide. This study aims to investigate the presence of plasmid-mediated verotoxin gene in non-O157 E. coli. Standard microbiological techniques identified a total of 137 E. coli isolates. The plasmid was detected by Perfectprep Plasmid Mini preparation kit. These isolates were subjected to disk diffusion assay, and plasmid curing with ethidium bromide treatment. The plasmid containing isolates were subjected to a polymerase chain reaction (PCR) for investigating

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Publication Date
Sun Jan 19 2014
Journal Name
Romanian Biotechnological Letters
Optimization conditions for bioemulsifier production by local Streptomyces sp. SS20 isolated from hydrocarbon contaminated soil
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Publication Date
Wed Aug 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Relationship between Alpha-toxin production and biofiJm for1nation by Staphylococcus aureus isolated from Eye's infections
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Staphylococcus aureus is a common pathogen associated  with eye·s

infections.  S. aureus is capable of biofilm fonnation, which increases its persistence and boots its levels of antimicrobial resistance . A total of 50

  1. aureus isolated from eyes <>f patientwith eye's infection : 41( 82%)

isolates  were positive - alpha tox in production and 37 (74 %)  isolates were  posilive  - biofilm formation .Where as  32 (64%)    isolates were positive - alpha toxin production .and biotilm formation, 11 (22%) Lsolatcs were negative- alpha toxin production and biofilm formation and 7(14%) isolates  were showed &nbs

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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of New Mannich Bases Derived from 7-hydroxy-4-methyl Coumarin
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Coumarin is a natural substance isolated from different plants. It belonges to a group of benzobyrones which consists of a benzene ring joined to a pyrone nucleus. In the present research, a new series of coumarin derivatives were formed. Compound (1) (7-hydroxy-4-methyl Coumarin) was converted into 4-methylquinolin-2(H) derivative (2) by reaction with acetamide, and then reaction of (2) with thiosemicarbazide in ethanol leads to the synthesize of hydrazincarbothioamide derivative (3).The reaction of (3) with ethylchloroacetate in presence of sodium acetate leads to closure ring to get [(1-(5-oxo-2-thioxoimidazolidin-1-ylimino) ethyl)]quinolin-2(1H)-one (4). Mannich bases were prepared through the reaction of (4) with primary

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Publication Date
Thu Apr 01 2021
Journal Name
Biochemical And Cellular Archives
Evaluation the Effect of Allium Sativum (garlic) oil on The Expression of Maz E and Maz F Genes in Escherichia Coli Clinical Isolates
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Publication Date
Tue Jan 01 2019
Journal Name
J. Pharm. Sci. & Res
Production of peroxidase from Providencia spp. bacteria
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Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
Production of Silicon Metal From Iraqi Sand
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In this work, production of silicon metal at high purity of 99% by using Iraqi–starting materials (Iraqi sand and plant coal)was reported, electric arc–furnaces assembly was manufactured inside, the graphite electrodes were made from graphite scrap, this system is operate to produce about 800 gm /6hr of silicon metal to meet the need for manufacturing silicon oils, resins, solar cells, and electronic parts. The procedure, equipments and analysis data were described as well.

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Production of Protease Enzyme from Wheat Straw
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      Protease enzyme production was studied and optimized as  a first step to collect information about solid state fermenter) to produce protease enzyme. A local isolated Aspergillus niger was used for this study with constant spores feeding in every experiment at (105/g). Experiments carried out in conical flasks with (250 ml) containing (10 g) of wheat straw as a substrate with different conditions included temperature, pH, hydration ratio, and fermentation time, the results comprised by measuring protease activity (u). The results showed that the best activity can be obtained at (T = 32°C, t= 100 hrs, pH= 2.5 and hydration ratio is 1:3). On the other hand the results is courage to p

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Publication Date
Sun Jul 23 2023
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Future of Engineered Phage Therapy for Clostridium difficile Infections
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Bacteriophages have the potential to eliminate both antibiotic-resistant and sensitive bacteria; as a result, they have become a major focus of such research. In contrast to antibiotics, which assault the entire bacterial population without discrimination, bacteriophages have a limited set of characteristics that allow them to target infectious microbes while avoiding friendly species (commensal microbiota). Nevertheless, large groups of naturally occurring bacteriophages that are well-differentiated and selective for the most clinically recognized pathogenic bacterial strains are required. Utilizing genetic engineering techniques that modify the target phage genome to synthesize phages with known characteristics in a brief period o

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Publication Date
Sat Dec 31 2022
Journal Name
Wasit Journal Of Computer And Mathematics Science
Cheating in E-learning from the perspective of lecturers within Iraqi universities
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Online examination is an integral and vital component of online learning. Student authentication is going to be widely seen when one of these major challenges within the online assessment. This study aims to investigate potential threats to student authentication in the online examinations. Adopting cheating in E-learning in a university of Iraq brings essential security issues for e-exam . In this document, these analysts suggested  a model making use of a quantitative research style to confirm the suggested aspects and create this relationship between these. The major elements that might impact universities to adopt cheating electronics were declared as Educational methods, Organizational methods, Teaching methods, Technical meth

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