The aim of the current study was to optimize different cultural and environmental conditions for production the antibacterial bioactive metabolites by Streptomyces rochei M78 isolated from agriculture soil, in Baghdad, Iraq. The effect of various parameters such as, culture media, incubation time, pH, carbon and nitrogen sources, C: N ratios and inducers on antibacterial metabolite production was studied by varying single parameter at a time. It was found from the results that higher metabolite production by isolate observed using starch casein broth (SCB) as the best production medium, at initial pH 7.0.Starch andcasein +yeast extract + peptone appeared to be the best carbon and nitrogen sources respectively and C: N ratio of 4: 1 after 72 h of incubation for optimal production of antibacterial metabolites.Optimization studies indicated that antibacterial metabolites production was associated with bacterial growth, and that the presence of inducers, such asedible oils and diesel oil as well as amino acids in the medium also enhanced antibacterial metabolites production.The most bioactive compounds were produced with soybean oil as the sole carbon source, and leucine as amino acid, yielding an inhibition zone more than 35 mm against all tested pathogenic bacteria.Among different solvents used for the extraction of antibacterial metabolite, ethyl acetate was found to be the best for solvent extraction of the metabolites yielding 2.18 g /l of red to brown extract with oily nature. The antibacterial activity of different extraction fractions of the metabolites showed that the ethyl acetate extract was the most active agent against tested pathogenic bacteria.Physiochemical characteristic of antimicrobial metabolites revealed that the antimicrobial metabolite was red to brown in color, having gummy and oily nature. The purified metabolite was soluble in different solvents, with a melting point of 150 °C. The metabolites of isolate M78 were stable at pH that varies from 4 – 11, maximum antibacterial activity was found at pH 7 and at temperatures ranging from 25 to 100 °C, maximum at 25 °C. Higher bactericidal concentration (BC) of the compound against Gram positive and Gram negative bacteria was determined as 250 μg/ml. The results showed that MBC values of the active metabolite had an impact at lower concentrations than those of standard antibiotic against tested pathogenic bacteria, suggesting that the metabolite was more effective.Theminimum inhibitory concentration value of compounds was 500 μg/ml against all tested bacterial isolates. Thin layer chromatography analysis of active metabolites showed two spots having an Rf value = 0.72 and 0.80.The FTIR spectrum of antibacterial compounds exhibited the presence of OH, C=O functional ester group, and C-H and CH3 groups in the structure. GC-MS analysis of active metabolites detected a total of 23 peaks; two major hydroxylated fatty acids were then identified as octadecanoic acid, 2-(2-hydroxy ethoxy) ethyl ester and tridecanoic acid, 3 methyl-, methyl ester with relative abundance of 100 and 33.63 % respectively.
God Almighty put in his great book secrets that do not end, and wonders that do not expire, for he is the one from which the scholars are not satisfied, and he does not create due to the multitude of response, and it is the comprehensive and inhibitory book that God conceals to the worlds, and he challenged the two heavyweights to come up with something like it.
At all times, issues arise in the Noble Qur’an that fit the needs of the people of that time and their culture, for it is an eternal book, characterized by the ability to give, extend and respond to addressing the problems of the age and its variables, when the Arabs had little luck at the time of the message’s descent from the scientific culture, and their proficienc
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Background: Ultrasonography has been used to examine the thickness of the lower uterine segment in women with previous cesarean sections in an attempt to predict the risk of scar dehiscence during subsequent pregnancy. The predictive value of such measurement has not been adequately assessed. Objectives: To correlate lower uterine segment thickness measured by trans abdominal ultrasound in pregnant women with previous cesarean section with that measured during cesarean section by caliper and to find out minimum lower uterine segment thickness indicative of integrity of the scar.Methods: A prospective observational study at Elwyia Maternity Teaching Hospital, from January 2011 to January 2012. A total of 143 women were enrolled in the stu
... Show MoreBackground: Measuring implant stability is an important issue in predicting treatment success. Dental implant stability is usually measured through resonance frequency analysis (RFA). Osstell® RFA devices can be used with transducers (Smartpeg™) that correspond to the implants used as well as with transducers designed for application with Penguin® RFA devices (Multipeg™). Aims: This study aims to assess the reliability of a MultiPeg™ transducer with an Osstell® device in measuring dental implant stability. Materials and Methods: Sixteen healthy participants who required dental implant treatment were enrolled in this study. Implant stability was measured by using an Osstell® device with two transducers, namely, Smartpeg™ and M
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The research amid to find out the extent of Iraqi oil companies commitment to implement internal control procedures in accordance with the updated COSO framework. As the research problem was represented in the fact that many of the internal control procedures applied in the Iraqi oil companies are incompatible with most modern international frameworks for internal control, including the integrated COSO framework, issued by the Committee of Sponsoring Organizations of the Tradeway Committee. The research followed the quantitative approach to handling and analysing data by designing a checklist to represent the research tool for collecting data. The study population was represented in the Iraqi oil companies, while the study sample
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Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a potent ligand for AhR and a known carcinogen. While AhR activation by TCDD leads to significant immunosuppression, how this translates into carcinogenic signal is unclear. Recently, we demonstrated that activation of AhR by TCDD in naïve C57BL6 mice leads to massive induction of myeloid derived-suppressor cells (MDSCs). In the current study, we investigated the role of the gut microbiota in TCDD-mediated MDSC induction. TCDD caused significant alterations in the gut microbiome, such as increases in Prevotella and Lactobacillus, while decreasing Sutterella and Bacteroides. Fecal transplants from TCDD-treated
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