Pure and Applied Chemistry

Bioantioxidants, or dietary antioxidants, are dietary substances in food that significantly decrease the adverse effects of reactive oxygen species (ROS) on normal physiological functions in humans. Inhibition of ROS-induced oxidative damages by supplementation of bioantioxidants, the so-called "antioxidant therapy", has become an attractive therapeutic strategy to reduce the risk of ROS-related diseases and has led to flourishing research in the past decade. However, many questions dealing with the correlation between chemical and biological activities, the bioavailability and "non-antioxidant" effects of bioantioxidants are still under debate.

This article outlines our current kinetic and mechanistic studies on naturally occurring antioxidants, including vitamin E, green tea polyphenols (GOHs), and resveratrol, as well as their synthetic analogs in micelles, in red blood cells, in low-density lipoprotein (LDL) and in microsomes. The cytotoxicity and apoptosis-inducing activity of these antioxidants against cancer cells were also studied. It was found that there was significant correlation between the chemical and biological antioxidant activities, as well as between the antioxidant activity and the cytotoxic and apoptosis-inducing activities.