Scavenging activity on reactive oxygen species with biological relevance by the Brazilian non-conventional spice Varronia curassavica

Varronia curassavica Jacq. is a Non-Conventional Edible Plant (spice) commonly found in Brazil used in folk medicine as anti-inflammatory. The present study aimed to investigate the in vitro antioxidant activity of the hydroethanolic extract of V. curassavica leaves (EtEVc) on reactive oxygen species with biological importance. The tests performed include O2•-, ROO•, HOCl/OCl-, H2O2 and ABTS•+/DPPH• capture. The putative identification of the major compounds was performed by UPLC-ESIQToF- MSE and in vitro cytotoxicity was evaluated. The antioxidant activity of EtEVc was very promising in all tests, highlighting on the capture of O2•-, which the EC50 value was three times lower than Trolox (EtEVc EC50 = 197 μg/mL and Trolox EC50 = 591 μg/mL); and it could be due to the presence of the major compounds, rosmarinic acid, salvianolic acid and quercetin derivates. EtEVc also presented low cytotoxicity. Thus, EtEVc has great potential for use as antioxidant agent.