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Attention is being focused on the coastline from Doha to Ras Laffan in Qatar since higher activities in the development of land and establishment of roads, highways and new buildings and houses is not coupled by serious studies on habitat destruction, fragmentation or disturbances. Ecophysiological study was carried out to investigate the adaptation of two halophytes (Limonium axillare and Avicennia marina) in this area, with special emphasis on the ultrastructure of salt glands found in the leaves. Soils in these locations accumulated much Na + and Cl − as compared to other cations like K + , Ca 2+ and Mg 2+ . Both plants accumulated higher concentrations of Na + , Cl − , and Ca 2+ and lower concentrations of K + and Mg 2+ . Organic compounds found in leaves of these plants under their natural habitats including proline, soluble sugars and nitrogen, and photosynthetic pigments were determined. Scanning electron micrographs of the surface of leaves showed that salt glands of these plants are well developed. It is urgently required that exact vegetation maps, and monitoring exercises will be conducted, in order to document exactly the state of the vegetation in Qatar. Only this will allow the environment authorities to bring forward suggestions for vegetation and ecosystem management to the decision makers.

Problem statement:The developing microbial resistance to the existing anti-microbial agents has become a real challenge and a serious problem facing patients suffering from skin infections. Seeds of Nigella sativa have been used for a long time in folk medicine for the treatment of such infections. Production of new potent agents is urgently needed, especially for hospitals and health centers. Therefore, the anti-microbial effect of aqueous, diethyl ether, chloroform and petroleum ether extracts of the seeds against four standard microbial strains and seven clinical isolates from patients with skin wound infections were investigated. Approach: The in vitro anti-microbial effect of the extracts at a concentration of 20% on standard strains and clinical isolates was assessed and compared with standard drugs, chloramphenicol and amphotericin B using agar well diffusion assay. The in vivo anti-bacterial effect of petroleum ether extract was studied in male BALB/c mice infected subcutaneously with S. aureus (ATCC 25923) or a clinical isolate (0.1 mL from 10 9 colony forming units mL −1 suspension) and immediately treated at the infected site by subcutaneous injection of 0.1 mL of pure extract (fixed oil) or chloramphenicol or normal saline. Counts of viable bacteria present in the skin area corresponding to the infected site were determined, after 24 and 48 h of infection and treatment. Results: The aqueous extract did not show any inhibitory effect against all the tested microorganisms. The diethyl ether and chloroform extracts indicated significant inhibitory effect only against Gram-positive bacteria. However, petroleum ether extract was proved to be the most powerful one against these bacteria and also against other clinical isolates like one Gram-negative bacterium (Klebsiella pneumonia) and the yeast (Candida albicans). Moreover, the extract revealed a superior effect over the standard drug, chloramphenicol, on the clearance of subcutaneous staphylococcal infection in mice when injected at the site of infection. Counts of viable bacteria were decreased at highly significant level in mice infected with S. aureus (ATCC 25923) or a clinical isolate. Conclusion/Recommendations:The results of this study revealed clear potentiality of N. sativa fixed oil as a source for anti-microbial drugs and support its use in folk medicine for the treatment of microbial skin infections.

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Nigella sativa has been used for a long time in Jordanian folk medicine to treat skin diseases like microbial infections and inflammation. Therefore, the present study was conducted to assess the healing efficacy of petroleum ether extract of Nigella sativa seeds (fixed oil) on staphylococcal-infected skin. Male BALB/c mice were infected with 100 microL of Staphylococcus aureus (ATCC 6538) suspension at a dose of 10(8) colony forming unit/mouse into shaved mild dorsal skin. Application of treatments for each group (100 microL sterile saline, 100 microL chloramphenicol (10 microg/mouse) and Nigella sativa fixed oil at a dose of 50, 100 or 150 microL/mouse) was performed at the site of infection twice a day for two consecutive days after 3 h of infection. At day 3 and 5 after infection, total White Blood Cells (WBCs) count; differential and absolute differential WBC counts and the number of viable bacteria present in the skin area were measured. At day 5 after infection, the animals were sacrificed and the histology of skin was examined. Results indicated that fixed oil of Nigella sativa seeds enhance healing of staphylococcal-infected skin by reducing total and absolute differential WBC counts, local infection and inflammation, bacterial expansion and tissue impairment. These effects provide scientific basis for the use of Nigella sativa in traditional medicine to treat skin infections and inflammations.