Piscicidal properties of piperovatine from Piper piscatorum (Piperaceae).

Extraction of the roots of the Amazonian medicinal plant, Piper piscatorum Trelease and Yuncker, with MeOH and subsequent bioassay guided fractionation using the guppy, Girardina guppii yielded the active amide, N-isobutyl-6-(p-methoxyphenyl) 2E, 4E-hexadieneamide (piperovatine) and a second inactive amide, N-isobutyl-(E)-7-(3,4-methylenedioxyphenyl)hept-2-enamide (pipercallosidine). The former displayed an LC50 of 115 ng/ml in toxicity tests and proved to be the constituent responsible for the dual ethnobotanical uses of this plant: that of fish stupefacient (barbasco) and oral local anesthetic.