Bilirubin as an antioxidant: kinetic studies of the reaction of bilirubin with peroxyl radicals in solution, micelles, and lipid bilayers.
Bilirubin (BR) showed very weak antioxidant activity in a nonpolar medium of styrene or cumene in chlorobenzene. In contrast, BR exhibited strong antioxidant activity in polar media such as aqueous lipid bilayers or SDS micelles/methyl linoleate (pH 7.4), where the rate with peroxyl radicals, k(inh) = 5.0 x 10(4) M(-)(1) s(-)(1), was comparable to that with vitamin E analogues, Trolox, or PMHC. An electron-transfer mechanism accounts for the effect of the medium on the antioxidant properties of BR.
Hatfield
Gillian L
GL
Department of Chemistry, Mount Allison University, Sackville, New Brunswick E4L 1G8, Canada.
Barclay
L Ross C
LR
D000975:Antioxidants / Q000737:chemistry*; D001663:Bilirubin / Q000737:chemistry*; D007700:Kinetics; D008051:Lipid Bilayers / Q000737:chemistry*; D008823:Micelles; D010545:Peroxides / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry
D000975:Antioxidants; D008051:Lipid Bilayers; D008823:Micelles; D010545:Peroxides; D012996:Solutions; C049375:perhydroxyl radical; D001663:Bilirubin