Scavenging capacity of berry crops on superoxide radicals, hydrogen peroxide, hydroxyl radicals, and singlet oxygen

The antioxidant activities against superoxide radicals (O-2(.-)), hydrogen peroxide (H2O2), hydroxyl radicals (OH.)(-), and singlet oxygen ('O-2) was evaluated in fruit juice from different cultivars of thornless blackberries (Rubus sp.), blueberries (Vaccinium spp.), cranberries (Vaccinium macrocar pon Aiton), raspberries (Rubus idaeus L. and Rubus occidentalis L.), and st rawberries (Fragaria x ananassa Duch.). Among the different cultivars, juic e of 'Hull Thornless' blackberry, 'Earliglow' strawberry,'Early Black' cran berry,'Jewel' raspberry, and 'Elliot' blueberry had the highest antioxidant capacity against superoxide radicals (O-2(.-)), hydrogen peroxide (H2O2), hydroxyl radicals (OH.), and singlet oxygen ('O-2). In general, blackberrie s had the highest antioxidant capacity inhibition of O-2(.-), H2O2, and OH. . Strawberry was second best in the antioxidant capacity assay for these sa me free radicals. With regard to 'O-2 scavenging activity, strawberry had t he highest value, while blackberry was second. Cranberries had the lowest i nhibition of H2O2 activity. Meanwhile, blueberries had the lowest antioxida nt capacity against OH. and 'O-2. There were interesting and marked differe nces among the different antioxidants in their abilities to scavenge differ ent reactive oxygen species. beta -Carotene had by far the highest scavengi ng activity against 'O-2 but had absolutely no effect on H2O2. Ascorbic aci d was the best at inhibiting H2O2 free radical activity. For OH., there was a wide range of scavenging capacities from a high of 15.3% with cr-tocophe rol to a low of 0.88% with ascorbic acid. Glutathione had higher O-2(.-) sc avenging capacity compared to the other antioxidants.