Laccase-Mediated Enhancement of the Antioxidant Activity of Propolis and Poplar Bud Exudates.

The treatment of propolis and poplar bud exudates with laccase from and 2,2,6,6-tetramethyl-1-piperidinyloxy free radical increased the antioxidant activity, as evaluated by the 2,2'-diphenyl picrylhydrazyl (DPPH)- and -butyl-OOH-induced DNA breakage comet assay analyses. The effect was highest for shorter reaction times. Propolis showed the highest antioxidant activity in the DPPH test, whereas poplar bud exudates were more active in reducing the -butyl-OOH-induced lesions in the Chinese hamster ovary cell line.