Department of Food Science and Technology, University of Nebraska-Lincoln, 68583-0919, USA.
The effects of 24 h supplementation of human colon carcinoma cells (Caco-2) with isoflavones, genistein, and daidzein and their activities against oleic acid hydroperoxide mediated oxidative stress were investigated. Genistein, at 25, 50, and 100 microM, and daidzein, at 25 and 50 microM, did not induce cell injury to Caco-2 cells. Both compounds reduced cell injury and DNA damage mediated by 5 microM oleic acid hydroperoxides in Caco-2 cells. The effects of genistein and daidzein on antioxidant enzymes were dependent upon the compound and its concentration.