title: New antioxidant flavonoid isolated from Leuzea carthamoides.
abstract: A new natural flavonoid patuletin 3'-beta-xylofuranoside was isolated from Leuzea carthamoides leaves. The antioxidant activity of this compound was evaluated by the DPPH radical assay and ferric reducing antioxidant power (FRAP) assay, and the results were compared with those for trolox and quercetin. DPPH radical scavenging activity of the tested compounds was expressed by the parameter EC50: patuletin 3'-beta-xylofuranoside (56.0 microM), trolox (27.8 microM), and quercetin (25.3 microM). The ferric reducing activity of the compounds was demonstrated as FRAP values at 4 and 60 min: patuletin 3'-beta-xylofuranoside (28.4 microM, 35.8 microM), trolox (19.3 microM, 20.2 microM), and quercetin (54.3 microM, 79.9 microM). The structure/activity relationship of the flavonoid is also discussed. The results indicate significant antioxidant potency of patuletin 3'-beta-xylofuranoside.
authors.affiliation: Department of Pharmaceutical Botany and Ecology, Faculty of Pharmacy, Charles University, Hradec Kralove, Czech Republic.
authors.forename: Vit
authors.initials: V
authors.lastname: Koleckar
authors.forename: Lubomir
authors.initials: L
authors.lastname: Opletal
authors.forename: Katerina
authors.initials: K
authors.lastname: Macakova
authors.forename: Ludek
authors.initials: L
authors.lastname: Jahodar
authors.forename: Daniel
authors.initials: D
authors.lastname: Jun
authors.forename: Jiri
authors.initials: J
authors.lastname: Kunes
authors.forename: Kamil
authors.initials: K
authors.lastname: Kuca
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D043843:Leuzea / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship
chemical_list: D000975:Antioxidants; D005419:Flavonoids