Bioactive compounds such as polyphenols are ubiquitous in many foods. However, their presence varies in structure, concentration, and action along food manufacturing and digestion. The simulated digestion assays allow to estimate variations in bioaccessibility and bioeffectiveness of polyphenols within foods. In this study, a polyphenols enriched food model was used: sweet cookies with 10% defatted sesame flour (DSF). Polyphenolic extracts were obtained from DSF, a base cookie formulation and cookies enriched with DSF. In addition, extracts of potentially bioaccessible polyphenols from digested cookies in vitro were collected. The HepG2 liver cell line was incubated with all these mentioned extracts and then injured with H2O2. The following parameters were analyzed: intracellular oxidative state and viability by flow cytometry, antioxidant enzymes and glutathione content, and oxidation of proteins and lipids by spectrophotometry.

Results show that DSF may be considered for functional incorporation in foods, since it may promote antioxidant response, providing preventive benefits and protective action in an oxidative damage context. This study also demonstrates that DSF actions on redox state vary depending on the food matrix and its degree of digestion. Cookies with DSF presented a pro-oxidant effect that could enhance the antioxidant response. Furthermore, after digestion, these cookies continue to show biological activity, evidencing the possibility of advantages from the consumption of these foods. This data remarks the need to improve the knowledge of the biological actions carried out by certain metabolites present in food and the impact of their digestion over their effective role in health.