Avaliação do potencial antioxidante e anti-Helicobacter pylori in vitro de extratos de plantas medicinais utilizadas popularmente na região amazônica

The Amazon region has an enormous diversity of plant species, which contributes to its known vast natural wealth. In this context, the aim of this work was to evaluate the antioxidant, anti-Helicobacter pylori and anti-urease potentials of medicinal plant extracts popularly used in the western Para, northern Brazil. Antimicrobial assays were carried out using spectrophotometric broth microdilution technique, the antioxidant potential by the DPPH and ABTS•+ assays and anti-urease activity by inhibition of the enzyme urease. The ethanolic extract of leaves of Schnella sp. showed the best antioxidant potential in both methods, with IC50= 6.35 μg/mL (DPPH) and 1.81 μg/mL (ABTS•+) and the highest percentage of inhibition of urease (45%) at 1024 μg/ml. The ethanolic extract of the resin of "breu-branco" inhibited 82.8% (512 μg/mL) of the bacterial growth. These results together show the potential of the plant species used in the western Para, in the search for molecules with antioxidant and antimicrobial action.