Preferred Language
Articles
/
ijcpe-822
Production of 7-methylxanthine from Theobromine by Metabolically Engineered E. coli
...Show More Authors

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. 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Materials Today: Proceedings
Studying the impact of condensate blockage on gas production: A review
...Show More Authors

When the drawdown pressure amounts to a value below the dew point pressure, a minor droplet of condensate is shaped and accumulated in the close area of wellbore. As the accumulation happens, the saturation of the liquid will grow and a reduction in gas relative permeability will happen, therefore it will affect the productivity. Generally, condensate baking problem in gas wells is being deliberated and studied and numerous techniques have been suggested to solve the problem. The studying of condensate banking dynamics is essential to evaluate the productivity and behavior of the wells of the gas fields.

Preview PDF
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sun Sep 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
New Development in the Process for the Production of Polybutadiene Rubber
...Show More Authors

View Publication Preview PDF
Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
Assessing EFL Learners Ability in the Recognition And Production of Homophones
...Show More Authors

This study deals with the orthographic processing ability of homophones
which can account for variance in word recognition and production skills due to
phonological processing. The study aims at: A)Investigating whether the students
can recognize correct usage and spelling comprehension of different homophones
by using appropriate word that overlapped in both phonology and orthography.
B)Assessing spelling production word association to the written form of the
homophone in the sentence comprehension task. To achieve these aims, two tests
have been conducted and distributed on 50 students at first stage at the College of
Education(Ibn-Rushd) for the academic year 2010-2011. The two tests are exposed
to a jury of

... Show More
View Publication Preview PDF
Publication Date
Mon Apr 01 2019
Journal Name
2019 4th Scientific International Conference Najaf (sicn)
Pneumatic Control System of Automatic Production Line Using SCADA Implement PLC
...Show More Authors

View Publication
Scopus (23)
Crossref (20)
Scopus Crossref
Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
The Formative Truth of the Dramatic Work between Direction and Production
...Show More Authors

Most of the theorists and researchers and also those interested in cinema and television attributed the fact of the existence of the dramatic works to the directors may be due to a historical justification. At the same time, the existence of the production world came as a result of the emergence of the production city (Hollywood). This is also a historic fact. The research would tackle all the formative truths to prove the relation and the timeline, i.e., before and after and the synergy that resulted in the existence of the dramatic works that benefited the humanity and those interested in this giving art. The objective of the research is to uncover the formative truth of the dramatic work between direction and production.

The s

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Apr 13 2020
Journal Name
International Journal Of Research Inpharmaceutical Sciences
The UV light effects on pectinase production of Pantoea sp. bacteria
...Show More Authors

Publication Date
Wed Feb 08 2012
Journal Name
Journal Of The College Of Education For Women
Assessing EFL Learners Ability in the Recognition and Production of Homophones
...Show More Authors

This study deals with the orthographic processing ability of homophones which can account for variance in word recognition and production skills due to phonological processing. The study aims at: A )Investigating whether the students can recognize correct usage and spelling comprehension of different homophones by using appropriate word that overlapped in both phonology and orthography. B )Assessing spelling production word association to the written form of the homophone in the sentence comprehension task. To achieve these aims, two tests have been conducted and distributed on 50 students at first stage at the College of Education(Ibn-Rushd) for the academic year 2010-2011. The two tests are exposed to a jury of experts for the purpose of

... Show More
View Publication
Publication Date
Sat Oct 08 2016
Journal Name
Methods In Molecular Biology
Production of Adjuvant-Loaded Biodegradable Particles for Use in Cancer Vaccines
...Show More Authors

View Publication
Scopus (9)
Crossref (8)
Scopus Clarivate Crossref
Publication Date
Mon Mar 01 2021
Journal Name
Iop Conference Series: Materials Science And Engineering
Purification and activation of the Iraqi bentonite for edible oil Production
...Show More Authors
Abstract<p>Samples of Iraqi bentonitic sediments, representing local montmorillonite brought from Traifawi region near the Syrian border. Mineralogical the samples were characterized as low grade of Ca-smectite, particle size, chemical analysis, XRD, and BET surface area analyses of the samples were carried out to examine the structure of bentonite before and after acid activation. The goal is to prepare a bleaching earth for edible oil production. Iraqi Bentonite was beneficiated and activated by series of physical and chemical steps, using 4N & 6N concentration of hydrochloric acid and at a temperature of 70-80 ° C. Surface area and pore volume of the samples were determined to assess the bleaching power</p> ... Show More
View Publication
Crossref (6)
Crossref
Publication Date
Thu Dec 01 2016
Journal Name
Chemical Engineering Science
Carbon dioxide rich microbubble acceleration of biogas production in anaerobic digestion
...Show More Authors

View Publication
Scopus (48)
Crossref (46)
Scopus Clarivate Crossref