الفهرس 
ACKNOWLEDGEMENTOnly 14 pages are availabe for public view
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Abstract
The aim of this work is to carry out phytochemical and biological study of secondary metabolites from Olea europaea leaves in order to discover new natural products with interesting biological activities. In this study, seventeen compounds were isolated and identified using various spectroscopic techniques. Some extracts and isolated compounds were screened for their cytotoxic activity, antimelanogenic activity, antilipase activity, α-glucosidase inhibition activity, antilipase activity and antiinflammatory activity. Part I: Phytochemical investigation of Olea europaea leaveTwo and half Kilograms of the powdered air-dried leaves of O. europaea extracted by maceration in a percolator with MeOH then fractionated into pet.ether, methylene chloride and EtOAc extracts respectively. Different extracts applied to silica gel column chromatography using gradient elution with different solvents. Similar fractions were pooled together and subjected to further purification. The isolated compounds were identified using various spectroscopic techniques including; UV, IR, 1D- and 2D-NMR and HRMS. Also with cochromatography with authentic samples. 17 compounds were identified as α-, β- amyrin mixture, β-sitosterol, uvaol and erythrodiol mixture, oleanolic acid, maslinic acid, vomifoliol which isolated for the first time from family oleaceae, β-sitosterol-glu., Luteolin, Luteolin 7-O- β-D-glu, diosmetin 7-O- β-D-glu, oleoside dimethyl ester, oleoside-11-methyl ester, oleuropein, secoxyloganin, hydroxypinoresinol 1-O- β-D-glu, verbascoside and hydroxytyrosol 8-O- β-D-glu and hydroxytyrosol 4’-O- β-D-glu mixture. Part –II Biological investigation of some extracts and the isolated compounds A- Biological evaluation of the cytotoxic activity by MTT assay against cancer and normal cel lines Luteolin is the most active compound against the five tested cell lines. vomifoliol is active against CaCo-2 cell line and oleuropein is active against HepG2 and HeLa cell lines B-Anti-melanogenic activities of compounds isolated from O. europaea using B16 melanoma cell line Verbascoside, luteolin, luteolin 7-O-glucosdie, diosmetin 7-O-glucosdie, hydroxyl pinoresinol 1-O-glucoside, oleoside 11-methyl ester, hydroxytyrosol 8-O-β-D-glucoside, hydroxytyrosol 4`-O-β-D-glucoside mixture and secoxyloganin exhibited melanin synthesis inhibition with low cytotoxicity C- Anti-allergic activitiy of compounds isolated from O. europaea leaves. verbascoside showed strong antiallergic activity D- Screening of the Inhibition of α-glucosidase by some compounds isolated from O. europaea leaves Oleanlic acid, maslinic acid and lueolin, out of the 12 compounds tested, exhibited a markable inhibition for this enzyme E- Screening of the antilipase activity of some compounds isolated from O. europaea leaves The strongest significant inhibitions for lipase enzyme were recorded for luteolin followed by diosmetin 7-O-glucoside then oleoside dimethyl ester F- Antiinflammatory activity of compounds isolated from O. europaea leaves: Vomifoliol, oleuropein, verbascoside, luteolin 7-O-glucoside and secoxyloganin, out of the 10 compounds tested, are COX-1 inhibitors.