The antimutagenic and antioxidant properties of various phenolic fractions obtained from Andean purple corn were examined by the Ames test and the DPPH antiradical assay. An anthocyanin-rich water fraction (WF) and an ethyl acetate fraction (EAF) showed a dose-dependent antimutagenic behavior against the food mutagen Trp-P-1 with IC50 values of 321.7 ± 21.36 and 95.2 ± 10.95 μg of chlorogenic acid equiv/plate, respectively, indicating that EAF was a more potent antimutagen. The antioxidant activities for WF and EAF were 1.019 ± 0.05 and 0.838 ± 0.11 μg of Trolox equiv/ μg of phenolics, respectively. Further fractionation of WF and EAF revealed an ethyl acetate subfraction, EA-IV, with high antimutagen potency that contained a quercetin derivative. The mechanism of antimutagenic action of the WF is predominantly a blocking effect on the S-9 Mix activation system of the mutagen, whereas for the EAF, it is a dual mechanism involving blocking of the S-9 Mix and a scavenging action on Trp-P-1 electrophiles.
- Antimutagenic activity
- Antioxidant activity
- Mechanism of antimutagenic action
- Phenolic compounds
- Purple corn extract