| Despite the long-standing use of Amelanchier fruits in juice, jelly and pies, very little work has been done on the isolation and characterization of bioactive compounds present in Amelanchier arborea and Amelanchier canadensis fruits. We have investigated bioactive compounds in Michigan grown Amelanchier alnifolia, Amelanchier arborea and Amelanchier canadensis. Bioassay-directed isolation and purification of the ethyl acetate extract of A. canadensis resulted in 1,3-dilinoleoyl 2-olein ( 4), 1,3-dioleoyl 2-linolein (5), and beta-sitosterol (6). Similarly, the methanol extract of A. canadensis fruits yielded cyaninidn-3-O-beta-galactopyranoside (1), cyaninidn-3-O-beta-galactopyranoside (2), cyaninidn (3), 5-hydroxymethyl-2-furfural ( 7), 5-(sorbitoloxymethyl)-furan-2-carboxaldehyde (8), 5-(mannitoloxymethyl)-furan-2-carboxaldehyde (9), 5-(alpha-D-glucopyranosyloxymethyl)furan-2-carboxaldehyde (10), and 5-(beta-D-glucopyranosyloxymethyl)furan-2-carboxaldehyde (11). The concentration of anthocyanins, 1 and 2, in A. alnifolia, A. arborea and A. canadensis were 155 and 54, 390 and 0, and 165 and 48 mg in 100 g of fresh fruits, respectively. Compounds 7--11 were isolated for the first time from A. canadensis fruits. The structures of these compounds were determined by various spectral techniques such as 1H- and 13C-NMR DEPT, HMQC, HMBC, MS and chemical methods.; A. arborea fruits were sequentially extracted with hexane, ethyl acetate and methanol. The separation and purification of ethyl acetate extract of A. arborea fruits yielded beta-sitosterol-3-glucoside (12), oleanolic acid (13), ursolic acid ( 14), kaempferol-3-O-alpha-L-rhamnopyranosyl (1 ← 2)rhmnopyranoside (15) and kaempferol-3-O-alpha-L-rhamnopyranoside (16).; Anthocyanins 1--3 at 10 ppm exhibited 70, 75, 78% of lipid peroxidation inhibitory activity, respectively. Compounds 8--11 , and 13--16 at 100 ppm exhibited 83, 26, 76, 85, and 83% lipid peroxidation inhibitory activity, respectively. Commercial antioxidant butylated hydroxy toluene (BHT) at 2.2 ppm gave 87% lipid peroxidation inhibitory activity. In cyclooxygenase enzyme inhibitory assay, compounds 1--3 at 100 ppm showed 50 and 18; 46 and 18; and 96 and 75% COX-1 and COX-2 enzyme inhibitory activity, respectively. Non steroidal anti-inflammatory drugs (NSAIDs) aspirin, celebrex and vioxx at 180, 1.67 and 1.67 ppm showed 74 and 69; 5 and 82; and 0 and 85% COX-1 and COX-2 inhibitory activity, respectively. Compound 4, mixtures of compounds 8 and 9 and 10 and 11 at 100 ppm gave 39 and 0; 68 and 49; 63 and 45% COX-1 and COX-2 inhibitory activity, respectively. Mixtures of compounds 13 and 14, and compound 15 at 100 ppm showed 4 and 6; and 16 and 15 of COX-1 and COX-2 enzyme inhibitory activities, respectively.; Lipid peroxidation inhibitory and COX enzyme inhibitory activities of the compounds isolated from Amelanchier fruits showed that the fruits contained many bioactive compounds. These results suggest that consumptions of Amelanchier fruits might be beneficial to human health. |
