Premium
Inhibition Mode of Soybean Lipoxygenase‐1 by Quercetin
Author(s) -
Ha Tae Joung,
Shimizu Kuniyoshi,
Ogura Tetsuya,
Kubo Isao
Publication year - 2010
Publication title -
chemistry and biodiversity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.427
H-Index - 70
eISSN - 1612-1880
pISSN - 1612-1872
DOI - 10.1002/cbdv.200900249
Subject(s) - quercetin , chemistry , lipoxygenase , rutin , ferrous , enzyme , linoleic acid , antioxidant , biochemistry , chelation , kaempferol , ferric , flavonoid , stereochemistry , organic chemistry , fatty acid
Quercetin noncompetitively inhibited the peroxidation of linoleic acid catalyzed by soybean lipoxygenase‐1 (EC 1.13.11.12, Type 1) with an IC 50 value of 4.8 μ M (1.45 μg/ml). This inhibition is considered to proceed in sequential order, by initially reducing the ferric form of the enzyme to an inactive ferrous form and then, by chelating the iron of the active site of the enzyme. In the pseudoperoxidase assay, quercetin was slowly oxidized by hydroperoxides to a rather stable intermediate, 2‐(3,4‐dihydroxybenzoyl)‐2,4,6‐trihydroxybenzofuran‐3(2 H )‐one, and this oxidized intermediate still inhibited the enzymatic oxidation, probably as a chelator. Rutin and kaempferol also exhibited lipoxygenase‐1 inhibitory activity, but to a much lesser extent than quercetin.