Interactions between flavonoids and proteins: effect on the total antioxidant capacity.
Flavonoids are potent antioxidants. It is also known that flavonoids bind to proteins. The effect of the interaction between tea flavonoids and proteins on the antioxidant capacity was examined. Their separate and combined antioxidant capacities were measured with the Trolox equivalent antioxidant capacity (TEAC) assay. It was observed that the antioxidant capacity of several components of green and black tea with alpha-, beta-, and kappa-casein or albumin is not additive; that is, a part of the total antioxidant capacity is masked by the interaction. This masking depends on both the protein and the flavonoid used. Components in green and black tea, which show the highest masking in combination with beta-casein, are epigallocatechin gallate and gallic acid. The results demonstrate that the matrix influences the efficacy of an antioxidant.
Arts
Mariken J T J
MJ
Department of Pharmacology and Toxicology, Faculty of Medicine, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands. Mariken.Arts@farmaco.unimaas.nl
Haenen
Guido R M M
GR
Wilms
Lonneke C
LC
Beetstra
Sasja A J N
SA
Heijnen
Chantal G M
CG
Voss
Hans-Peter
HP
Bast
Aalt
A
D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D001628:Beverages; D002364:Caseins / Q000737:chemistry; D002417:Cattle; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology; D008892:Milk; D011392:Proline / Q000032:analysis; D011506:Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013662:Tea
D000975:Antioxidants; D002364:Caseins; D005419:Flavonoids; D011506:Proteins; D013662:Tea; D012710:Serum Albumin, Bovine; D011392:Proline