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Hydrophobicity and amounts of polar groups on the cell surface were determined by the use of fluorescent probe, colloid titration, and acid titration. Surface hydrophobicity of hydrocarbon-grown cells was about 7 times greater than that of glucose-grown cells of the same strain, while amounts of polar groups did not differ so much. Adsorption of cells to air bubbles was maximum at pH 3. Langmuir’s adsorption isotherm held for the adsorption. Affinity to air bubbles of hydrocarbon-grown cells was 1.8 times greater than that of glucose-grown cells, while the theoretical maximum amounts of cells to adsorb per unit area of bubbles were equal for the both cells. 相似文献
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狼毒大戟三萜类和酸类化合物的分离鉴定 总被引:10,自引:0,他引:10
用溶剂提取和硅胶柱色谱方法,从狼毒大戟中分得两个三萜化合物和一个酸类化合物,经物理常数和色谱分析鉴定为羽扇豆酮、羽扇豆醇乙酯和没食子酸。 相似文献
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The structure of a new antibacterial biphenyl, atylosol, from Atylosia trinervia was elucidated as 3-hydroxy-4-isopentenyl-5-methoxybiphenyl. In addition, lupenone, lupeol and sitosterol were also isolated. 相似文献
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A complex mixture containing more than 20 4-demethylsterols, 4-monomethylsterols and triterpenes was isolated from the grains of Sorghum vulgare. Seventeen of these compounds were identified using a combination of GLC, GC-MS, IR and NMR. 相似文献
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Sudharsan PT Mythili Y Selvakumar E Varalakshmi P 《Molecular and cellular biochemistry》2006,292(1-2):39-44
Cyclophosphamide (CP), an alkylating agent widely used in cancer chemotherapy causes cardiac membrane damage. Lupeol, a pentacyclic triterpene, isolated from Crataeva nurvala stem bark and its ester, lupeol linoleate possess a wide range of medicinal properties. The effect of lupeol and its ester was evaluated in CP induced alterations in cardiac electrolytes in rats. Male albino rats of Wistar strain were categorized into 6 groups. Group I served as control. Rats in groups II, V and VI were injected intraperitoneally with a single dose of CP (200 mg/kg body weight) dissolved in saline. CP treated groups V and VI received lupeol and lupeol linoleate (50 mg/kg body weight) respectively, dissolved in olive oil for 10 days by oral gavage. At the end of the experimental period, urinary risk factors, activities of ATPases and electrolytes were measured using standard procedures. CP administered rats showed a significant decrease (P < 0.001) in the activities of ATPases. It was associated with significant alterations (P < 0.001) of electrolytes both in serum and cardiac tissue. The levels of urea, uric acid and creatinine were also significantly (P < 0.001) altered in the serum and urine. Lupeol and its ester showed reversal of the above alterations induced by CP. These findings demonstrate that the supplementation with lupeol and its ester could preserve membrane permeability, highlighting their protective effect against CP induced cardiotoxicity. 相似文献