The antioxidative activity of skin or flesh extracts and the polyphenolic composition during the
fruit development were examined in three different cultivars of apple (Malus sylvestris (L.) Mill. var.
domestica (Borkh.) Mansf.); `Fuji' with red skin, `Oorin' with yellow skin, and `Red®eld', a cider
apple. The IC50 values of superoxide (O2 À ) and 1-diphenyl-2-picrylhydrazyl (DPPH)-radicalscavenging activities remained low throughout fruit development in the skin of the three cultivars.
The IC50 values of the activities in the ¯esh of `Fuji' and `Oorin' were low at the beginning, but
increased toward the ripening stage. In contrast, the IC50 values of the activities in the ¯esh of
`Red®eld' remained low throughout fruit development. Chlorogenic acid, phloridzin, (‡)-catechin,
and (À)-epicatechin were detected as polyphenolics in the skin and ¯esh of the three cultivars. In
general, the concentrations of (‡)-catechin and (À)-epicatechin in the skin and ¯esh of `Red®eld'
were higher than those in `Fuji' and `Oorin'. Total phenolic concentrations on the fresh weight basis
in the skin and ¯esh of three cultivars decreased towards the ripening stage. However, the total
phenolic concentrations of `Red®eld' were higher than those of `Fuji' and `Oorin'. These results
demonstrate that the free-radical-scavenging activity in apple skin and ¯esh may depend on the
concentration and composition of polyphenolics.
# 2002 Elsevier Science B.V. All rights reserved.