Cellular antioxidant activity measurement: An alternative to chemical antioxidant methods?

Oxidative stress occurs when the production of reactive oxygen species (ROS) overpasses their degradation and buffering by endogenous antioxidants and those derived from the diet (exogenous antioxidants). In food science and nutrition, assessing antioxidant activity relies on chemical reactions—chemical test-tube assays—and human and murine cell lines. Usually, an ROS inductor, such as hydrogen peroxide (H₂O₂) or peroxyl radicals (ROO^•), is used to induce oxidation. Some biomarkers related to endogenous protection (i.e., catalase, superoxide dismutase, and glutathione reductase), oxidation-end products (i.e., malondialdehyde), and intracellular ROS generation can be quantitatively determined. Herein, some insights into using human cell lines and related biomarkers are described, and the downsides of using chemical antioxidant assays are explained. In conclusion, research on antioxidants should be based on using relevant human cell cultures. In contrast, chemical antioxidant assays should be limited to an initial screening as their physiological importance is negligible.