reported that the high molecular
weight phenolics such as tannic acid have more ability to quench ABTS radical and the effectiveness depends on the
molecular weight, the number of aromatic rings and nature
of hydroxyl groups’ substitution than the specific functional
groups. Phenolic compounds capable of donating hydrogen
atom were more effective in scavenging ABTS radical
(Leong and Shui 2002). The results suggested that different
extracts had the varying capacity of scavenging ABTS
radicals.