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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.

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Much attention is being focused on the Black barley (Hordeum distichum L.) as a local cultivar offering good model for a cereal crop has traits of resistance to drought and salinity during vegetative growth stages. Although Black was sensitive to salt stress during germination, it developed gradual tolerance with age and proved very tolerant during growth and development stages. The data of study clearly revealed how this cultivar was superior over Arivat (Hordeum vulgare L.) in many physiological aspects such as leaf growth variables (i.e. rate and duration) and processes (i.e. cell division), tiller production and potassium content. Black barley had more tillers, faster rate and longer duration of growth processes which was accompanied with potassium accumulation, as sodium chloride concentration increased in the growth medium. Thus, the ability of Black cultivar to accumulate K + could have promoted growth variables (i.e. faster rate and longer duration of growth processes). Arivat, on the other hand, might have suffered from K + deficiency; which could explain the adverse effect of salt stress on leaf growth variables and processes. Moreover, the relative water content (RWC) and proline can clearly distinguish the two cultivars; RWC was higher and proline concentration was lower in leaves of Black as compared with Arivat. Therefore, Black barley proved efficient in maintaining growth, ion homeostasis, and might sacrifice less in growth under osmotic stress conditions. The possible mechanism of the effect of sodium chloride on potassium accumulation in Black barley is discussed.

Ethanol extract of mixed algae-spirogyra and ulothrix was investigated to assess the effect on some biochemical parameters in UVB irradiated mice. The dorsal-thoracic region of mice were shaved and exposed to UVB radiation for 24 h for two consecutive weeks. Five groups of ten mice each were conducted: non-irradiated control and irradiated control. Mice treated with commercial cream (S.M.) at a dose of 0.1 mg/cm 2 and mice treated with ethanol extract of mixed spirogyra and ulothrix at a dose of 0.1 mg/cm 2 or 0.2 mg/cm 2 . Topical application was performed to all treated mice groups once a day for four consecutive weeks.Results showed significant differences between treated and control groups during the whole period of experiment. The clear potentiality of the ethanol extract was detected through body and skin weight, level of total protein, Superoxide Dismutase (SOD) and Catalase (CAT) activities in skin. However, UVB irradiated mice treated with 0.2 mg/cm 2 exhibited the most significant effect when compared to control groups. That may be attributed to anti-inflammatory and anti-oxidant effects of algal extract.