Effect of in vitro digestion of yerba mate (Ilex paraguariensis A. St. Hil.) extract on the cellular antioxidant activity, antiproliferative activity and cytotoxicity toward HepG2 cells

- The influence of in vitro gastrointestinal digestion of yerba mate was investigated in HepG2 cells.
- Phenolic compounds and total antioxidant activity of yerba mate extract decreased after digestion.
- Digested yerba mate extract promoted lower CAA and inhibition of HepG2 cell proliferation.
- No difference was observed in the cytotoxicity of HepG2 cells after in vitro digestion.

The aim of this study was to evaluate the influence of the in vitro gastrointestinal digestion of yerba mate extract on the cellular antioxidant activity (CAA) and cytotoxic and antiproliferative action toward HepG2 cells. The total reducing substances, isolated phenolic acids, total flavonoids and total antioxidant activity of the yerba mate extract decreased significantly after in vitro digestion. The digested extract promoted lower CAA and inhibition of HepG2 cell proliferation when compared to the non-digested extract (P < 0.05). No significant difference was observed in the cytotoxicity assay. Dose-response correlations were found for both yerba mate extracts for CAA, antiproliferative activity and cytotoxicity. The simulated gastrointestinal digestion of yerba mate extract promoted a significant decrease in the phytochemical content, total antioxidant activity, CAA and inhibition of HepG2 cell proliferation. Nevertheless, digested yerba mate extract still has considerable CAA and antiproliferative activity, which merits further investigation in in vivo studies.