The activity of anti-browning was also correlated with the
antioxidant activity that was proportional to their phenolic content
(Sulaiman et al., 2011). The antioxidant activity of the oxalic
acid treated fruit is also in correlation with the amount of phenolics
present in the extracts from tissues (Contreras-Calderón et al.,
2011; Loganayaki et al., 2010). In this study, the treated fruit
contained higher phenols and stronger reducing power as compared
with untreated fruit. Our previous study also indicated that
the oxalic acid could attribute to the fruit storage accordingly to
improve the antioxidant activity (Huang et al., 2013). However,
the mechanism behind how the oxalic acid treatment affects the
phenol content and interaction with the PPO, and POD enzymes in
postharvest fruit at a molecular level is still not completely known.