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
Thu Dec 01 2011
Journal Name
Journal Of Engineering
REMOVAL OF COPPER ION FROM WASTEWATER BY FLOTATION
...Show More Authors

Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal
before the discharge or reuse of treated waters could take place. In this paper, the removal of copper( II)
by foam flotation from dilute aqueous solutions was investigated at laboratory scale. The effects of
various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow
rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside
diameter and 120 cm height. Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide
(HTAB) were used as anionic and cationic surfactant, respectively. Ethanol was used as frothers and the

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Thu Jul 31 2025
Journal Name
Communications In Science And Technology
Effect of CaO nanocatalyst on bio-oil production from algae and date seeds via microwave-assisted co-pyrolysis
...Show More Authors

One of the most effective ways of managing solid waste is microwave-assisted pyrolysis. This research used MW-assisted catalytic co-pyrolysis to extract essential oils from algae powder (AP) and date seed (DS). Graphite and a CaO nanocatalyst were utilized. As for the feedstock, it was a 1:1 mixture of AP and DS. The char content, oil production, and gas generation of co-pyrolysis yields varied between 18.8 wt% and 24.31 wt%, 43.08 wt%, and 55.295 wt%, and 25.905% to 32.60 wt%, respectively. The effect of the CaO nanocatalyst on product yields, feedstock conversion, and heating rates was analyzed. Product yields, average heating rates, and conversion factors were among the metrics studied to determine the synergistic effects and pyr

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Study of total Immunoglobulin E and Eosinophil count in allergic disease
...Show More Authors

The present study aimed to evaluate the levels of total immunoglobulin E and percentage count of eosinophil in some of allergic disease. Blood sample collected from 210 patients (110 female, 100 male) with allergic disease (allergic asthma, allergic rhinitis, and urticaria) their age between 10-70 years and 50 healthy control their age between 23-52 years. A highly significant (P<0.01) increase in the mean serum total IgE in patients with asthma (503.54 ± 63.49 IU/ml), Allergic rhinitis (442.77 ± 95.76 IU/ml) and urticaria (489.53 ± 69.68 IU/ml) as a compared with healthy controls (23.67 ± 5.81 IU/ml).There was a significant difference in percentage count of eosinophil in patients groups allergic asthma 4.37 ± 0.52% ,allergic rhinitis

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Biotech Research
Bacteriocin Production by Staphylococcus Epidermidis the Normal Flora of Outer Ear: A Potential Probiotic Against Outer Ear Infections
...Show More Authors

Scopus (2)
Scopus
Publication Date
Thu Sep 25 2025
Journal Name
Energy Procedia
Production of Hydrogen and Nanocarbon by Catalytic Decomposition of Electrocracking Gas over an Industrial Catalyst under Integrated Reactor Conditions
...Show More Authors

Hydrogen and nanocarbon were produced by the catalytic decomposition of electrocracking gas obtained by the pyrolysis of liquid organic waste via electric arc discharge. The GIAP-16 (NiO-Al2O3) industrial catalyst was used to reduce the maximum decomposition temperature to 700 °C. In a fixed-bed reactor, under atmospheric pressure, reasonable amounts of high-purity hydrogen were produced, accompanied by deposits of nanocarbon by-product. The NiO-Al2O3 catalyst showed excellent catalytic activity. X-ray powder diffraction analysis of the NiO-Al2O3 composite revealed the presence of cubic NiO and rhombohedral Al2O3, which were chemically stable. However, above 500 °C, NiAl2O4 began to appear. The specific surface area of the catalyst was de

... Show More
Publication Date
Sat Mar 01 2025
Journal Name
Iranian Journal Of Immunology
Soluble HLA-E and Gastroesophageal Reflux Disease: A Novel Association
...Show More Authors

Gastroesophageal reflux disease (GERD) is a prevalent clinical condition, that affects millions of individuals worldwide. Objective: To assess the level of soluble HLA-E (sHLA-E) as a biomarker in the diagnosis and immunopathogenesis of GERD patients. Methods: The case-control prospective study included 40 GERD patients who were consulted at the Gastroenterology Unit of AlKindy Teaching Hospital, as along with 40 healthy control subjects. The study period extended from January 2023 to May 2024. Blood was drawn from both groups and serum was separated to assesssHLA-E using a sandwich enzyme-linked immunosorbent assay (ELISA) kit. Results: There was a statistically significant difference in sHLA-E levels between GERD patients and healthy cont

... Show More
Scopus
Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
REMOVAL OF PHENOLIC COMPUNDS FROM AQUEOUS SOLUTIONS BY ADSOPTION ONTO ACTIVTED CARBONS PREPARED FROM DATE STONES BY CHEMICAL ACTIVATION WITH FeCl3
...Show More Authors

Activated carbon prepared from date stones by chemical activation with ferric chloride (FAC) was used an adsorbent to remove phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) from aqueous solutions. The influence of process variables represented by solution pH value (2-12), adsorbent to adsorbate weight ratio (0.2-1.8), and contact time (30-150 min) on removal percentage and adsorbed amount of Ph and PNPh onto FAC was studied. For PNPh adsorption,( 97.43 %) maximum removal percentage and (48.71 mg/g) adsorbed amount was achieved at (5) solution pH,( 1) adsorbent to adsorbate weight ratio, and (90 min) contact time. While for Ph adsorption, at (4) solution pH, (1.4) absorbent to adsorbate weight ratio, and (120 min) contact

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Tue Jan 01 2013
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Classification and Construction of (k,3)-Arcs on Projective Plane Over Galois Field GF(7)
...Show More Authors

The purpose of this work is to study the classification and construction of (k,3)-arcs in the projective plane PG(2,7). We found that there are two (5,3)-arcs, four (6,3)-arcs, six (7,3)arcs, six (8,3)-arcs, seven (9,3)-arcs, six (10,3)-arcs and six (11,3)-arcs. All of these arcs are incomplete. The number of distinct (12,3)-arcs are six, two of them are complete. There are four distinct (13,3)-arcs, two of them are complete and one (14,3)-arc which is incomplete. There exists one complete (15,3)-arc.

Publication Date
Wed Dec 29 2021
Journal Name
Modern Sport
Building and measuring e-learning scale from the point of view of students of the College of Physical Education and Sports Sciences - University of Baghdad
...Show More Authors

Abstract: The research covered five chapters:       So, the first chapter definition of the research is from the introduction to the research and its importance, as the importance of the research lies in an expression of the reality of e-learning as it is one of the new patterns of the educational process and its role in enhancing communication and interconnectedness between the learners from the students ’point of view Physical Education and Sports Sciences for Girls, University of Baghdad, as for the problem The research was, and through the researcher’s acquaintance with many previous studies, references and sources, and being a student at the College of Physical Education and Sports Sciences - University of

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 01 2021
Journal Name
Turkish Journal Of Physiotherapy And Rehabilitation
ISSN 2651-4451 | e-ISSN 2651-446X
...Show More Authors

Record, verify, and showcase your peer review contributions in a format you can include in job and funding applications (without breaking reviewer anonymity).

View Publication