Antioxidative flavonoids from leaves of Carthamus tinctorius.
A total of eight flavonoids (1-8), including a novel quercetin-7-O-(6''-O-acetyl)-beta-D-glucopyranoside (6) and seven known flavonoids, luteolin (1), quercetin (2), luteolin 7-O-beta-D-glucopyranoside (3), luteolin-7-O-(6''-O-acetyl)-beta-D-glucopyranoside (4) quercetin 7-O-beta-D-glucopyranoside (5), acacetin 7-O-beta-D-glucuronide (7) and apigenin-6-C-beta-D-glucopyrano syl-8-C-beta-D-glucopyranoside (8), have been isolated from the leaves of the safflower (Carthamus tinctorius L.) and identified on the basis of spectroscopic and chemical studies. The antioxidative activity of these flavonoids was evaluated against 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by hydroxyl radicals generated via a Fenton-type reaction. Among these flavonoids, luteolin-acetyl-glucoside (4) and quercetin-acetyl-glucoside (6) showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin (1), quercetin (2), and their corresponding glycosides (3 & 5) also exhibited strong antioxidative activity, while acacetin glucuronide (7) and apigenin-6,8-di-C-glucoside (8) were relatively less active.
Department of Food Science and Nutrition, Catholic University of Daegu, Hayang, Gyeongbuk, Korea.
Jun Young
JY
Lee
Eun Ju
EJ
Chang
Hyo Jin
HJ
Kim
Jun Hong
JH
Park
Sang Won
SW
Choi
D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D031178:Carthamus / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003855:Deoxyribose / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D017665:Hydroxyl Radical / Q000737:chemistry; D066298:In Vitro Techniques; D015227:Lipid Peroxidation / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D017392:Thiobarbituric Acid Reactive Substances / Q000737:chemistry
D000975:Antioxidants; D005419:Flavonoids; D017392:Thiobarbituric Acid Reactive Substances; D017665:Hydroxyl Radical; D003855:Deoxyribose