Abstract

ANGIOTENSIN-CONVERTING ENZYME INHIBITION BYPHTHIRUSA PYRIFOLIA(KUNTH) EICHER

Rodrigo Andrés Restrepo Osorio; Olga Alicia NietoCárdenas;Javier AristizabalFranco, *Patricia Landazuri

ABSTRACT

Angiotensin-converting enzyme (ACE) is part of the renin-angiotensin system and is responsible for the synthesis of angiotensin II, a potent vasoconstrictor, which relates it with the development of cardiovascular risk factors such as hypertension. Phthirusa pyrifolia, ascarcely studied species in matters of its biological activity, was evaluated in vitro to demonstrate its ability to inhibit ACE by the method used for determining the activity of this enzyme in serum, based on the enzymatic hydrolysis of Furylacryloyl - L - phenylalanyl - glycyl – glycine(FAPGG), for serum ACE, until Furylacryloyl - L - phenyl and glycyl - glycine (Gly - Gly). Inhibition percentages of 75.9 ± 10.4 % and 33.4 ± 9.4 % were found for the ethanolic extract of this species working in a reaction mixture concentration of 0.05 and 0.025 mg/mL, respectively. In addition, its toxicity against Artemia salina was determined finding a LD50of 38.6 μg/mL.These results allow to consider Phthirusa pyrifoliaas an important source of ACE inhibitory metabolites and suggest that this species may have a high toxic potential, which raises the need for toxicological studies of greater depth.

Keywords: Hypertension, angiotensin-converting enzyme inhibition, Phthirusa pyrifolia.