6-hydroxyflavonoids as alpha-glucosidase inhibitors from marjoram (Origanum majorana) leaves.
A methanol extract of marjoram leaves strongly inhibited rat intestinal alpha-glucosidase. Five 6-hydroxyflavonoids, 6-hydroxyapigenin (scutellarein; IC50 for sucrose hydrolysis by rat intestinal alpha-glucosidase, 12 microM), 6-hydroxyapigenin-7-O-beta-D-glucopyranoside (> 500 microM), 6-hydroxyluteolin-7-O-beta-D-glucopyranoside (300 microM), 6-hydroxyapigenin-7-O-(6-O-feruloyl)-beta-D-glucopyranoside (>500 microM), and 6-hydroxyluteolin-7-O-(6-O-feruloyl)-beta-D-glucopyranoside (> 500 microM), were isolated as active principles and related compounds. The two feruloylglucosides are novel compounds.
Laboratory of Food Biochemistry, Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo 060-8589, Japan. junk@chem.agr.hokudai.ac.jp
Jun
J
Kawabata
Kenji
K
Mizuhata
Eri
E
Sato
Tetsuo
T
Nishioka
Yoritaka
Y
Aoyama
Takanori
T
Kasai
D000818:Animals; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D020128:Inhibitory Concentration 50; D019906:Nuclear Magnetic Resonance, Biomolecular; D031341:Origanum / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats
D004791:Enzyme Inhibitors; D005419:Flavonoids; D065089:Glycoside Hydrolase Inhibitors