phase radicals) and of chain-breaking antioxidants (scavengers of
lipid peroxyl radicals) in many plant extracts (Leong & Shui, 2002).
The effect of hydrothermal temperature and time on the ABTS RSA
of the watermelon extracts is shown in Table 2. The ABTS RSA also
increased with increase in the temperature and time used for
treatment. In the case of the flesh part, the ABTS RSA increased from
15.09% in untreated control to 97.86% by hydrothermal treatment at
300 C for 30 min. The white rind extracts showed relatively lower
ABTS RSA than the extracts of the other parts of the watermelons.