Amazonian pataua (Oenocarpus bataua) pulp extract: bioaccessibility of phenolic compounds and effects on cellular antioxidant and antimalarial activities

This study assessed the effect of simulated human digestion on the phytochemical properties and antioxidant capacity of Amazonian pataua (Oenocarpus bataua) pulp extract in human cells and plasma, and the antimalarial effect against Plasmodium falciparum. The composition of the pulp extract before and after in vitro digestion was analysed by liquid chromatography. Eleven polyphenols were identified and quantified, where (+)-catechin, vanillic acid and isorhamnetin were the primary compounds. The initial screening of the water-ethanol extract (50:50 v/v) showed cytotoxicity against normal cells after digestion, justified by increased intracellular reactive oxygen species (ROS). When subjected to an in vitro digestion process, the extract's oxygen radical absorbance capacity, iron-reducing capacity, and human plasma protection were adversely decreased. However, undigested and digested pataua pulp extracts could reduce intracellular reactive oxygen species generation in red blood cells. Moreover, both undigested and digested pataua pulp extracts showed antimalarial activity against Plasmodium falciparum, with the digested extract being more promising due to its higher potency and greater selectivity, as indicated by a lower IC₅₀ and higher selectivity index. This study provides a solid foundation for rationally exploiting pataua as a novel source of biologically active compounds.