Chemical Composition and Schistosomicidal Activity of Essential Oils of Two Piper Species from the Amazon Region

The essential oils of Piper marginatum Jacq and Piper callosum Ruiz & Pav were obtained by hydrodistillation and tested in vitro against the adult worms of Schistosoma mansoni species. The chemical constituents were evaluated by Gas chromatography / Mass spectrometry. The main constituents of the essential oil of the leaves of P. marginatum were 3,4- (methylenedioxy) propiophenone (10.41 %), bicyclogermacrene (10.16 %) and germacrene D (9.93 %). The extraction of the aerial parts (branches, leaves and inflorescences) from P. callosum provided two essential oils, one of them being transparent and of greater density than the water presenting safrole (29.32 %), alpha-pinene (19.23 %) and beta-pinene (14.31 %) as major constituents and another yellow oil of smaller density than the water with 92 % safrole. The essential oils exhibited a dose-dependent effect on decreased motor activity and death of parasites. The essential oil of P. marginatum caused death of 100 % of the parasites in the concentration of 50 mu g/mL, while the PC+ (denser than water) and PC- (less dense than water) samples obtained from P. callosum caused 100 % death in the concentration of 100 mu g/mL.