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Alexandria, Egypt

Taha T.H.,King Khalid University | Taha T.H.,GEBRI Institute | Alamri S.A.,King Khalid University | Mahdy H.M.,Al - Azhar University of Egypt | And 2 more authors.
Journal of Biological Sciences | Year: 2013

Bioavailability and environmental stress are problems affecting Poly Aromatic Hydrocarbons (PAH) biodegradation. This study aims to overcome the effect of PAH boavailability via biosurfactant production and the effect of environmental stresses via using different immobilization matrices. Three different PAH bacterial degraders (A2, P5 and N7) were immobilized in different immobilization matrices. The immobilization matrices used in this investigation were: ca-alginate, agar-agar and agarose. RAPD-PCR, plasmid profile and 16S rRNA sequencing methods were used to identify and group the bacterial isolates. The production of biosurfactant was detected using the methylene blue analysis procedure. The results indicated that P5 and N7 isolates preferred the alginate matrix compared to the agar and agarose matrices, where biosurfactant production was 136 and 165.5 mg L-1 for both isolates, respectively. However, the A2 isolate produced a higher biosurfactant concentration (132.4 mg L-1) when grown on agarose. The preferred matrices for the three isolates were different in the presence of hydrocarbons. The A2 and P5 isolates preferred agar as the best matrix for biosurfactant production. On the other hand, the free cells of the N7 isolate produced the highest concentration of biosurfactant compared to immobilized cells. The overall results of this study showed that the type of preferred immobilization matrix depends on the used carbon source; where, in general, calcium alginate was preferred at the presence of glucose while agar was preferred at the presence of hydrocarbons. © 2013 Asian Network for Scientific Information. Source

Sarhan M.A.A.,King Khalid University | Osman A.A.,King Khalid University | Haimour W.O.,Assir Central Hospital Laboratory | Mohamed M.N.,Medical internist Bashair Hospital | And 3 more authors.
Indian Journal of Medical Microbiology | Year: 2014

Background: The genus Acinetobacter is a diverse group of Gram-negative bacteria involve at least 33 species using the molecular methods. Although the genus Acinetobacter comprises a number of definite bacterial species, some of these species are of clinical importance. Therefore, it is of vital importance to use a method which is able to reliably and efficiently differentiate the numerous Acinetobacter species. Objectives: This study aims to identify Acinetobacter of clinical isolates from Assir region to the species level by 16S-23S intergenic spacers internal transcribed spacer (ITS) of ribosomal ribonucleic acid (rRNA). Materials and Methods: Deoxyribonucleic acid extraction, polymerase chain reaction amplification of 16S-23S intergenic spacer sequences (ITS) was performed using the bacterium-specific universal primers. Results: Based on the 16S-23S intergenic spacers (ITS) of rRNA sequences, all isolates tested were identified as Acinetobacter baumannii. The isolates shared a common ancestral lineage with the prototypes A. baumannii U60279 and U60280 with 99% sequence similarities. Conclusion: These findings confirmed 16S-23S rRNA ITS for the identification of A. baumannii of different genotypes among patients. Source

Abu-Saied M.A.,Advanced Technology and New Materials Research Institute | Hafez E.E.,Egyptian Plant Protection Res Institute | Taha T.H.,King Khalid University | Taha T.H.,GEBRI Institute | And 2 more authors.
International Journal of Nanoparticles | Year: 2014

Poly (methyl 2-methylpropenoate) PMMA [(C5O2H8)n] and bionanosilver are known to have inhibitory and bactericidal effects. In this study, Bacillus subtilis was used to produce bionanosilver particles that were characterised using SEM and FE-SEM. The bionanosilver were mixed with PMMA and dissolving in dimethylformamide (DMF) to produce bionanosilver-nanofibre (bionanofibre) using electrospun. The surface morphology was investigated by SEM. The activity of bionanofibre was examined as antibacterial against nine human pathogenic bacteria and the results were compared with different generic antibiotics. The bionanofibre showed high antibacterial activity and it was found that bionanofibre more specific for Methicillin-resistant Staphylococcus aureus (MRSA) especially in liquid culture with low concentrations. Copyright © 2014 Inderscience Enterprises Ltd. Source

El-Adawi H.,GEBRI Institute | El-Azhary D.,Menoufia University | El-Wahab A.A.,GEBRI Institute | El-Shafeey M.,GEBRI Institute | Abdel-Mohsen M.,Medical Research Institute
Journal of Medicinal Plant Research | Year: 2011

Fumonisin B1 (FB1) is a mold metabolite produced by Fusarium species that is frequently found in corn worldwide, it is toxic to both liver and kidney. Hepato- and nephro-toxicity were induced in rats by feeding them with FB1 contaminated corn. Evidence of those toxicities were observed after 60 days by an increase in the serum activity alanine aminotransferase (ALT) to 78%, creatinine to 65% and urea to 30%, in comparison with control group (p = 0.000). Pretreatment with silymarin (S), or grape seeds (G) extracts or both (S+G) was found to return the ALT activity to normal. In case of creatinine, S and S+G lowered the level down to 22 and 24%, respectively and G could successfully return it to normal. The pretreatment S, G, and S+G could significantly reduce urea level to 52, 37 and 46%, respectively. FB1 drastically depleted glutathione peroxidase (GPx) to 48%, while pretreatment with S, G, and S+G could elevate the GPx by 30, 31 and 50%, respectively. Lipid peroxidation represented by malondialdehyde (MDA) was elevated significantly to 137% and the pretreatment with S, G, and S+G altered the levels down to 38, 37, and 44%, respectively. Significant improvement in lipid profile was also observed in all pretreated groups. These improvements might be due to the free radical scavenging properties of S and G and its ability to enhance endogenous antioxidant defenses. ©2011 Academic Journals. Source

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