Lipid peroxidation inhibitory activity of components isolated from Caesalpinia paraguariensis stem bark infusion

SGARIGLIA, M.A.; SOBERÓN , J.R.; SAMPIETRO, D.A.; QUIROGA, E.N.; VATTUONE, M.A.

Santa María de Punilla, Córdoba, Argentina

Congreso; II Reunión De Biotecnología Aplicada a Plantas Medicinales y Aromáticas; 2009

CEPROCOR - REDBIO – UNCOR

The lipid peroxidation (LP) is a chain reaction initiated by free radicals which produce oxidative damage on polyunsaturated fatty acids. The lipid oxidation is implicated in physiopathology of atherosclerosis. The stem bark of Caesalpinia paraguariensis, was used in argentine north as water additive of "mate" in order to diminish blood cholesterol level or prevent the atherosclerosis. We investigated the infusion, their purified fractions and compounds isolated by bioguided purification, according to their ability to inhibiting the LP in biological membranes. Lyophilized infusion (10%, w/v) was extracted with ethyl ether, chloroform, and methanol (MF). MF was fractionated using Sephadex LH-20/methanol. Fractions were analyzed by thin layer chromatography (TLC). Fill and FX were selected to isolate substances by RP-HPLC. Four bioactive compounds were obtained and these were characterized by one-dimensional and bi-dimensional TLC, 254 and 365 nm UV light, plus different chemical reagents and co-injections with standard substances. The LP inhibitory activity was assayed in human erythrocyte membranes. IC50 was the concentration (μg/ml) of the compounds required for a 50% inhibition of the LP, ± S.D. BHT was used as referent substance. IC50 for infusion was 0.50±0.04. The purified fractions Fill and FX were bioactive (IC50: 1.33 and 2.50±0.02). From Fill were isolated M10, M21 and M17, identified as Gallic acid , 3,3'-di-O-methylellagic-4-0-~-D-xylopiranoside acid and an methyl derivative of Ellagic acid (IC50= 1.80; 15.00 and 0.50±0.05, respectively). From FX was isolated M25, IC50= 1.30±0.07, identified as Ellagic acid. BHT showed IC50=1 00.00±0.1O. These compounds were reported for the first time for this species.