The antioxidant role of bile pigments evaluated by chemical tests.
Bilirubin, biliverdin and their serum albumin complexes were tested as oxyradical scavengers (superoxide generated by the xanthine/xanthine oxidase system and peroxyl radical-trapping antioxidant ability). As superoxide scavengers the free bile pigments showed activities near to that of serum albumin, higher than the water soluble vitamin E analog Trolox and lower than ascorbic acid. The peroxyl radical-trapping antioxidant abilities of the tested bile pigments were much higher than those of the serum albumin and of the same order as their serum albumin complexes. This interaction with peroxyl radicals showed different stoichiometric factors for bilirubin (approximately 2) and biliverdin (approximately 4).
Farrera
J A
JA
Departament de Química Orgànica, Universitat de Barcelona, Catalonia, Spain.
Jaumà
A
A
Ribó
J M
JM
Peiré
M A
MA
Parellada
P P
PP
Roques-Choua
S
S
Bienvenue
E
E
Seta
P
P
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001654:Bile Pigments / Q000737:chemistry / Q000494:pharmacology*; D001663:Bilirubin / Q000737:chemistry / Q000494:pharmacology; D001664:Biliverdine / Q000737:chemistry / Q000494:pharmacology; D002417:Cattle; D016166:Free Radical Scavengers; D006801:Humans; D066298:In Vitro Techniques; D010084:Oxidation-Reduction; D012709:Serum Albumin / Q000737:chemistry; D013481:Superoxides / Q000737:chemistry
D000975:Antioxidants; D001654:Bile Pigments; D016166:Free Radical Scavengers; D012709:Serum Albumin; D013481:Superoxides; D001664:Biliverdine; D001663:Bilirubin