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Production of 7-methylxanthine from Theobromine by Metabolically Engineered E. coli

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
Sun Jul 02 2006
Journal Name
Journal Of The Faculty Of Medicine Baghdad
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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Study the Effect of Face Sheets Material on Strength of Sandwich Plates with Circular Hole

This study aims to investigate the effect of changing skins material on the strength of sandwich plates with circular hole when subjected to mechanical loads. Theoretical, numerical and experimental analyses are done for sandwich plates with hole and with two face sheet materials. Theoretical analysis is performed by using sandwich plate theory which depends on the first order shear deformation theory for plates subjected to tension and bending separately. Finite element method was used to analyse numerically all cases by ANSYS program.

The sandwich plates were investigated experimentally under bending and buckling load separately. The relationship between stresses and the ratio of hole diameter to plate width (d/b) are built, by

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Publication Date
Sun Jan 02 2011
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Comparison Effect Of Vitamin C Vaginal Tablet Versus Oral Metronidazole For Treatment Of Bacterial Vaginosis

Back ground: Bcaterial vaginosis is an important gynecological problem, during reproductive age group with high relapse rate ,it is associated with high vaginal PH, vaginal vitamin C recently tried to decreased vaginal PH and treat bacterial vaginosis.
Patients & Methods: One hundred and one women with Bacterial vaginosis their age range from 18-40 years enrolled in this study, the Diagnosis is confirmed by at least 3out of 4 of (Amsel criteria) which include a thin homogenous vaginal discharge, vaginal PH of ≥4.7, a characteristic ''amine odour'' release when alkali (lo% KOH) is added to a specimen of vaginal fluid, and at least 20% of epithelial cells having the appearance of clue cell in a wet mo

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Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Approximate Analytical Solutions of Bright Optical Soliton for Nonlinear Schrödinger Equation of Power Law Nonlinearity

This paper introduces the Multistep Modified Reduced Differential Transform Method (MMRDTM). It is applied to approximate the solution for Nonlinear Schrodinger Equations (NLSEs) of power law nonlinearity. The proposed method has some advantages. An analytical approximation can be generated in a fast converging series by applying the proposed approach. On top of that, the number of computed terms is also significantly reduced. Compared to the RDTM, the nonlinear term in this method is replaced by related Adomian polynomials prior to the implementation of a multistep approach. As a consequence, only a smaller number of NLSE computed terms are required in the attained approximation. Moreover, the approximation also converges rapidly over a

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Publication Date
Wed Sep 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Histological Evaluation of Effect of beta-Tricalcium Phosphate on Bone healing in Alloxan-Induced diabetes

Background: Improved glucose level control with insulin injections have allowed for the diabetic population to live longer and healthier lives. Unfortunately diabetes remains a worldwide epidemic disease with multiple health implications. Specifically, its effects upon fracture healing are compromised in diabetics with as high as 87% recovery delay relative to “healthy” counterparts. Current medical treatments for bone injuries have been largely focused on replacing the lost bone with allogenic or autogenous bone grafts, beta-tricalcium phosphate (β -TCP), a ceramic alloplast, has interconnected system of micropores, has been widely used as a biologically safe osteoconductive bone substitute. The aim of this study was histol

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Publication Date
Wed May 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Gross and Histological Structure of the Caudal Fin of Adult Mosquitofish , Gambusia Affinis , (Baird & Girard)

The  present  study  showed  that  the  caudal  fin  of  adult mosquitofish  (Gambusia  affinis)  is  homocercal  and  rounded . It  consists  of  22-24 fin rays (Lepidotrichia) . Each fin ray  consists  of  many  segments . Some of these rays are short and  unbranched  whereas  others long and branched dichotomously. Pigment cells are shown to be dispersed on the fin and they are condensened at the edges of the fin rays and at the regions of their dichotomy .        Histologically the transverse section of the fin is surrounded by a fin membrane (composed of epidermis and dermis)

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Publication Date
Sun Jan 03 2016
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Biological Impact of Gold Nanoparticle on Estradaiol and Testosterone Levels in Sera of Human Males

Background: There is a little information on the potential nanoparticle risk to human health, particularly on the sex hormones.
Objectives: the present study aims to investigate the impact of gold nanoparticles potential toxicity on the levels of sex hormones testosterone (T) and estradiol (E2) in sera of human males
Patients and methods: a total of 25 healthy men volunteers aged (20-45) years participated. Four types of gold nanoparticles were used to study their impact on estradiol and testosterone levels.
Results: The results indicated inhibiting effect of gold nanoparticles on E2 level and activating effect on T level .The low impact of T/E2 by gold nanoparticles was executed at 20μl serum.
Conclusion: different types of

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Publication Date
Fri Oct 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Environmental pollution of solid waste and methods of managing it Study in Ramadi Municipality Case

The current research aims at finding out how to properly and correctly manage waste and solid waste and reduce the difficulties faced by all countries. However, it is becoming increasingly acute in developed cities because their economies are growing rapidly. It is necessary to identify the modern methods used in developed countries in managing wastes. The use of modern waste management techniques is a coordinated effort by international agencies within the borders responsible for them. The problem of the study can be identified in the lack of clarity of environmental management procedures in place. The importance of the research contributes to providing greater capacity to the administrative and technical leadership in the municipality

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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
The effect of uncertainty in adopting the general requirements of strategic environmental assessment /exploratory study

Abstract                                                                  

The aim of the research is to demonstrate the role of uncertainty in adopting the general requirements for the strategic environmental assessment of service departments in Babil Governorate and the Environment Department. By focusing on a range of environmental problems, despite the efforts exerted to deal with the environme

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Publication Date
Sun Apr 30 2023
Journal Name
Al-kindy College Medical Journal
Estimation of Salivary IL-6 Level in relation of Periodontal Status in Patients with Hyperthyroidism

Background: The overproduction of thyroid hormones is known as hyperthyroidism. Increased susceptibility to caries and periodontal disease are two potential oral symptoms. The interleukin-6 (IL-6) was observed to significantly increased in the hyperthyroid group. According to multiple research, IL-6 dysregulation has been linked to a number of oral disorders, including periodontal diseases. The study aimed to evaluate periodontal health status in relation to IL6 among hyperthyroidism patients.

Subjects and Methods: The sample was composed of 90 female patients aged 25-45 years attending endocrine disorder

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