Antioxidant Effect of Apple Polyphenols by Flow Injection Chemiluminescence

Abstract

The antioxidant effect of apple polyphenols extract in vitro was determinated by flow injection analysis chemiluminescence (FIA-CL). The ascorbic acid was used as positive control. Inhibition by apple polyphenols extract or ascorbic acid of the steady chemiluminescence emissions of various oxidants with luminol was measured. IC₅₀ values of apple polyphenols extract were calculated: 0.47 μg/mL, for superoxide (O₂^•–), 0.20 μg/mL, for hydoxyl (^•OH), 0.21 μg/mL, for hydrogen peroxide (H₂O₂). Thus apple polyphenols extract exerted an excellent antioxidant activity towards reactive oxygen species (ROS) and more than that of ascorbic acid. The antioxidant effect of apple polyphenols extract on H₂O₂ is much better than O₂^•–, but is equal to ^•OH. This suggests that apple polyphenols is an excellent natural antioxidant.