Water soluble antioxidant capacity of different teas: Determination by photochemiluminescence.

Abstract

The water sol. antioxidant capacity of different tea infusions deriving from fermented tea, green tea, white tea, red tea and other specialties was examd. by photochemiluminescence (PCL). The evaluations were expressed as capacity of the given infusion to counteract the superoxide anion O2 .ovrhdot. one of the most dangerous reactive oxygen species. The activity may vary in great extent depending on the evaluation method chosen, because the different methods account for activity against different oxidized and radical species. The antioxidant capacity was expressed as mmol equiv. in activity of ascorbic acid, detd. in the best exptl. conditions for each sample and indicated the following potencies in descending order: brancha green tea > Italian GDO fermented tea > lung ching green tea> Italian GDO baobab flavored green tea > Italian GDO ginseng flavored fermented tea > pai mu tang white tea > Italian GDO fermented tea > worldwide GDO mint flavored tea> Assam black tea > worldwide GDO orange/cinnamon flavored fermented tea >> roibos> oolong brown tea