Abstract  Successive petroleum ether, chloroform and methanol extracts of Mappia foetida leaves and stem were tested for their antibacterial activity. The methanol fractions were found to be most effective against all the tested organisms. (C) 2002 Elsevier Science B.V. All tights reserved.

Abstract  A strain, Pseudomonas sp. X-2-45, with high and stable lipolytical activity was screened by continuously subculturing a lipase-producing bacterium P. sp. LP-1 in culture medium containing Jatropha oil as a sole carbon source. Its hydrolytic activity was 29.79 U/mL, which was increased by 288% as compared to that of parent strain. Furthermore, the growth and lipase synthesis of X-2-45, its catalytic ability to hydrolyze vegetable oils, as well as ester synthesis between fatty acids and organic alcohols were studied. Results showed that rates of bacterial growth and lipase synthesis were significantly raised. Bacterial biomass and lipase activity reached the highest level after 30 h of incubation. Moreover, growth stationary period was prolonged and lipase produced exhibited good stability in culture media during incubation period. Hydrolytic activity of P. sp. X-2-45 lipase toward Jatropha oil was increased by 378% as compared to parent strain, suggesting that acclimation to Jatropha oil was an effective approach for improving substrate selectivity of lipase. Finally, results of ester synthesis catalyzed by P. sp. X-2-45 lipase indicated that this lipase could catalyze esterification reactions between lauric acid and n-butanol, n-octanol, 1-dodecanol or glycerol, palmitic acid or stearic acid and methanol, n-octanol, 1-dodecanol or glycerol, oleic acid and methanol, n-butanol, n-octanol, 1-dodecanol or glycerol.

Abstract  A HPLC method has been developed for the simultaneous characterisation of anthraquinone glycosides and aglycones in extracts of Rubia tinctorum L. The anthraquinones are separated on an end-capped C inferior 1 inferior 8-RP column with a water-acetonitrile gradient as eluent and measured with UV detection at 250 nm. With this method the glycosides lucidin primeveroside and ruberythric acid and the aglycones lucidin, alizarin, purpurin, quinizarin and 2,6-dihydroxyanthraquinone can be analysed. Lucidin which is not commercially available was synthesised starting from resorcinol and phthalic anhydride. The glycosides ruberythric acid and lucidin primeveroside are commercially available as a mixture and were separated by droplet counter-current chromatography in ascending flow with chloroform-methanol-water as eluents prior to their use as standards. Copyright (C) 1998 Elsevier Science B.V.

Abstract  Interest in indoor air-quality is steadily increasing. Exposure to volatile organic compounds (VOCs) is associated with health hazards on diverse childhood respiratory problems, lung cancer and cardiovascular disorders. In an effort to assess the impacts of diverse plausible sources such as i) open oil lakes, ii) chemical and petrochemical industries and iii) indoor pollution from household items on the air quality indoors, we have measured a range of aliphatic VOCs from n-hexane to n-hexadecane, and aromatics such as benzene, toluene, xylene, ethyl benzene, methanol and o-dichlorobenzene in indoor and outdoor air samples from 7 cities in Kuwait, using gas chromatograph. The data did not show a relative rise in airborne VOCs during the months March to May 1993. Although, the cumulative effects of certain VOCs that entered the human body and water sources cannot be ruled out.

Abstract  The hexane, ethylacetate and methanol extracts of Polygonum hydropiper whole plant administered to mice at doses of 250 and 500 mg/kg, showed a significant activity on acetic acid-induced writhing. Within the tested extracts, the ethylacetate one showed the most significant activity.

Abstract  The n-hexane, dichloromethane and methanol extracts of the aerial parts of Glechoma hederacea have been screened for antibacterial and free radical scavenging activity. General toxicity (brine shrimp lethality assay) of these extracts has also been assessed.

Abstract  The total alkaloid fraction of the methanol extract of unripe fruits of Solanum pseudocapsicum was tested for in vitro cytotoxicity on HEp-2, RD and Vero cell lines and anti-tumor activity using DLA and HEp-2 cell lines. Cell viability and morphological changes were assessed. The total alkaloid fraction exhibited strong cytotoxic activity against all the cell lines tested. The CTC 50 (50 % of cytotoxicity inhibition) was found to be 1.65 µg/ml for the RD cell line, 6.32 µg/ml for the HEp-2 cell line and 12.01 µg/ml for the Vero cell line. In the clonogenic assay, no colony formation was observed even up to a concentration of 25 µg/ml. In the short term, antitumor, studies using DLA cells, the total alkaloid fraction was associated with 50 % viability in the concentration range of 6.25-12.5 µg/ml. In long term, anti-tumor activity using the HEp-2 cell line, no colony formation was observed up to a concentration of 20 µg/ml. Hence, there is a correlation between the results obtained in the cytotoxicity and antitumor studies carried out. Morphological observation by phase contrast microscopy revealed intense damage on all the cell lines. The total alkaloid fraction has the potential for further investigation in animal models.

Abstract  A sensitive and precise method is described to assay the oilseed canola (Brassica napus L.) for ergosterol, a fungal metabolite indicating spoilage. The ground seed is refluxed in methanol, and the methanol extract is saponified with potassium hydroxide. After addition of water, the mixture is partitioned into n-hexane. The n-hexane extract is dried, reconstituted, and applied to a silica solid-phase extraction cartridge, which is then washed with carbon tetrachloride, and eluted with acetone. The acetone eluate is acetylated, and the ergosterol determined as the acetate by liquid chromatography using a reverse-phase column and absorbency detection at 282 nm. Acetylation is necessary since an unidentified constituent of the matrix co-chromatographs with free ergosterol, and the ergosterol peak cannot otherwise be resolved. Using a 2-h acetylation at 60°C, recoveries of 10 and 25 ppm added ergosterol were 96.3% and 94.0%, respectively (n = 4, relative SD=3.8% in each case). Results using a convenient overnight acetylation at 37°C were similar and not significantly different. The limit of detection was approximately 0.3 ppm. Crown Copyright © 2002 Published by Elsevier Science Ltd. All rights reserved.