Protective Effects of Purple Waxy Corn on Aflatoxin B1-induced Oxidative Stress and Micronucleus in HepG2 Cells

Abstract

The purpose of this study was to investigate the protective effects of purple waxy corn extract (Zea may L.) on aflatoxin B1-induced cytotoxicity, oxidative stress and micronuclei in HepG2 cells. Purple waxy corn extract contained phenolics (187.15-341.65 µg gallic acid/mg), flavonoids (0.55-21.35 µg quercetin/mg) and anthocyanins (43.70-220.43 mg cyanidin-3-glucoside/l). Antioxidant activities of the extracts were measured using oxygen radical absorbance capacity (1410.70-2214.49 µM trolox/mg) and ferric reducing/antioxidant power (292.38-612.38 µM trolox/mg) assays. There were significant correlations between phenolic, flavonoid and anthocyanin content and antioxidant activities (R= 0.740-0.778) of purple waxy corn extract. Studies in HepG2 cells found that 0.5 and 1 mg/ml purple waxy corn extract increased cell viability in AFB1-treated HepG2 cells. Purple waxy corn extract reduced intracellular ROS production, increased GSH content and antioxidant enzyme GR, GPx and GST activities and micronucleus in aflatoxin B1-treated HepG2 cells. Therefore, purple waxy corn extract reduced aflatoxin B1 toxicity through induction of antioxidant activities and, thus, inhibited oxidative stress-induced DNA damage caused by aflatoxin B1.