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
Fri Jan 17 2020
Journal Name
Cihan University-erbil Scientific Journal
Characterization of Lactobacillus Isolates from Human Mouth and Feces as Probiotics
...Show More Authors

Probiotics are live microbes that give many health benefits to human beings and animals, the most studied and commonly used probiotics are Gram-positive bacteria; lactobacilli and bifidobacteria. At nowadays, Lactobacillus spp. constitute more than two-thirds of the total numbers of probiotic species. The present study aimed to characterize Lactobacillus that locally isolated from human mouth and feces as probiotics. A total of three Lactobacillus isolates; Lactobacillus fermentum Lb2, Lactobacillus rhamnosus Lb9, and Lactobacillus paracasei Lb10 were investigated in respect to acid and bile salts tolerance, antibiotics susceptibility, and cell surface hydrophobicity in vitro using bacterial adhesion to hydrocarbons method. In compa

... Show More
View Publication
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
University Of Bucharest Rom Biotechnol Printed In Romania.
Antibiotic resistance determinants of Acinetobacter baumannii strains isolated from nosocomial infections
...Show More Authors

Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
Effect of aqueous extract from Marjoram against Salmonella and cholera bacteria
...Show More Authors

Five different bacterial isolates [ Vibrio cholera (Ogawa) , Vibrio cholera (Inaba) , Salmonella typhi , Salmonella paratyphi and ? Salmonella typhimurium ] were obtained from the Central Health Laboratory . Both sensitivity tests (MIC , MBC and wells method ) against these bacteria were performed by using the aqueous of leaves extract of Marjoram plant. The results cleared that the values of MIC for Vibrio cholera serotypes Ogawa and Inaba were 100 mg/ml , while the value of MBC was 200 mg/ml. The value of the Inhibition zone at 100 mg /ml concentration for both Ogawa and Inaba were 13 mm and 9 mm respectively. Our results showed that the three types of Salmonella didn’t show any inhibition zone at 200 mg/ml .

View Publication Preview PDF
Crossref
Publication Date
Sat Mar 30 2013
Journal Name
College Of Islamic Sciences
 The choices of Ibn Muqasim (354 AH) from the Qur’anic readings
...Show More Authors

This research examines aspects of Imam Al-Qurtubi's efforts in matters related to the topics of faith that he dealt with in his interpretation (the provisions of the provisions of the Qur’an); and it has been shown that Imam Al-Qurtubi in most of the doctrinal issues dealt with in his interpretation approximates the doctrine of the Sunnis of Ash'aris, Maturids and people of impact. He had responses to some of the teams, such as stereoscopic, karami, and Mu'tazilite, reinforcing the responses with transfer and mental evidence.
    It was found that Imam Al-Qurtubi says that there is an increase in faith and a decrease in it, that the increase is through actions (so obedience increases and decreases in sin) and that the

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 31 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Extraction of Aromatic Hydrocarbons from Lube Oil Using Different Co-Solvent
...Show More Authors

An investigation was conducted effect of addition co- solvent on solvent extraction process for two types of a lubricating oil fraction (spindle) and (SAE-30) obtained from vacuum distillation unit of lube oil plant of Daura Refinery. In this study two types of co-solvents ( formamide and N-methyl, 2, pyrrolidone) were blended with furfural to extract aromatic hydrocarbons which are the undesirable materials in raw lubricating oil, in order to improve the viscosity index, viscosity and yield of produced lubricating oil. The studied operating condition are extraction temperature range from 70 to 110 °C for formamide and 80 to 120 °C for N-methyl, 2, pyrrolidone, solvent to oil ratio range from 1:1 to 2:1 (wt./wt.) for furfural with form

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Extraction of Iron from Al-Hussainyat Iron Ore using Acid Leaching
...Show More Authors

View Publication Preview PDF
Publication Date
Thu Jul 05 2018
Journal Name
International Journal Of Medical Research & Health Sciences
Methicillin-Resistant Staphylococcus epidermidis Isolated from Breast Tumors of Iraqi Patients
...Show More Authors

Background: Globally, breast cancer is the second leading cause of death among women in Iraq. Several genetic and environmental factors are associated..

View Publication Preview PDF
Publication Date
Sun Sep 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Preparation and Agglomeration of Zeolite 5A from Locally Available Raw Materials
...Show More Authors

View Publication Preview PDF
Publication Date
Fri Jul 01 2011
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
A NEW SPECIES OF RHYNCOMYAROB.-DESVOIDY, 1830 (DIPTERA : CALLIPHORIDAE) FROM IRAQ
...Show More Authors

This research includes a detaile description of new species Rhyncomya irakensis sp. nov.
from Iraq.
Localities distribution, host plants and data of collection were recorded.

View Publication Preview PDF
Publication Date
Tue Dec 21 2021
Journal Name
Journal Of Engineering Mathematics
Fluid inflow from a source on the base of a channel
...Show More Authors

View Publication
Crossref