Isolation and identification of alpha-glucosidase inhibitors from tochu-cha (Eucommia ulmoides).
alpha-Glucosidase inhibitory activity was found in aqueous methanol extracts of tochu-cha, dried leaves of Eucommia ulmoides (Eucommiaceae). Five active principles against yeast enzyme were isolated and characterized. Among them, quercetin (1, Ki: 8.5 x 10(-6) M) was considered to contribute mostly to the activity of the tochu leaves. In regard to an animal alpha-glucosidase, rat intestinal sucrase activity was also inhibited by 1.
Watanabe
J
J
Department of Bioscience and Chemistry, Faculty of Agriculture, Hokkaido University, Sapporo, Japan.
Kawabata
J
J
Kurihara
H
H
Niki
R
R
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D007422:Intestines / Q000187:drug effects / Q000201:enzymology; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D011794:Quercetin / Q000031:analogs & derivatives / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats; D013057:Spectrum Analysis; D013393:Sucrase / Q000037:antagonists & inhibitors; D013662:Tea
D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D010936:Plant Extracts; D013662:Tea; D011794:Quercetin; D013393:Sucrase