The antioxidant activity of extracts from FSW and USW, determined
by ABTS radical scavenging effect, is shown in Fig 3A.
As shown in Fig. 3A, FSW and USW extracts showed good ABTS
radical scavenging activity. At 0.1–1.2 mg/ml, the ABTS radical
scavenging activity of USW extracts ranged from 6.92 to 63.42
%, while it ranged from 27.79 to 94.92% for FSW extracts. FSW
and USW are free radical inhibitors or scavengers, acting possibly
as primary antioxidants. Antioxidant activity of natural
antioxidants has been shown to be involved in the termination
of free radical reactions (Lee et al., 2008). FSW and USW
extracts might react with free radicals, particularly of the peroxyl
radicals, which are the major propagators of the autoxidation
chain of fat, thereby terminating the chain reaction
(Shahidi, Janitha, & Wanasundara, 1992).