الفهرس 
Chapter I: IntroductionOnly 14 pages are availabe for public view
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Abstract
Background: The extensive literature survey revealed that Terminalia bellerica, is an important medicinal plant with diverse pharmacological spectrum. However, the phytochemical studies on the leaves of Terminalia were very rare. This prompted our interest to carry out an extensive phytochemical study on the leaves of Terminalia grown in Egypt. Methods: In this study we report for the first time phytochemical screening, investigation of antioxidant, antibacterial, cytotoxicity and anti-HIV as well as antifungal activities of seven different successive extracts namely; 70% methanol, petroleum ether, diethyl ether, dichloromethane, ethyl acetate, butanol and aqueous extracts of Terminalia bellerica Roxb. leaves. The bioactive ethyl acetate and n-butanol soluble parts of successive methanol extract of leaves of Terminalia bellerica were subjected to column chromatography for separation of different chemical constituents. Results and Discussion: Three hydrolysable tannins, four flavonol glycoside, one flavone and two flavonolaglycone were identified. The identification of the structures of isolated compounds was occurred using 1D- and 2D-NMR, UV and MS. Compounds 3-10 were reported for the first time from Terminalia bellerica leaves. The 70% methanol, diethyl ether and butanol extracts showed strong antioxidant activity compared to ascorbic acid and rutin as positive controls. Only, 70% methanol extract showed good anti-HIV activity. The 70% methanol, ethyl acetate, butanol and aqueous extracts showed good antibacterial activities against Micrococcus flavus, Staphylococcus aureus and Escherichia coli compared to the antibiotics streptomycin® and ampicillin®. All extracts except diethyl ether, showed very high antifungal activities against eight investigated fungal strains compared to that of fungicides bifonazole® and ketoconazole® (positive controls). Conclusion: The results of this study revealed that, this plant may be utilized as promising sources of therapeutics, as strong antioxidant as well as antifungal from natural sources.