ISLA Maria Ines
Antioxidant and XOD inhibitory coumarins from Pterocaulon polystachyum DC
VERA N. ZAMPINI I.C., ISLA M.I., BARDÓN A
NATURAL PRODUCTS COMMUNICATION
Natural Product, Inc
Lugar: USA; Año: 2007 vol. 2 p. 551 - 556
The antioxidant capacity of prenyletin (6-hydroxy-7-isoprenyloxycoumarin (1), prenyletin-6-methylether (6-methoxy-7-isoprenyloxycoumarin (2), and ayapin (6,7-methylenedioxycoumarin (3), isolated from an Argentine collection of Pterocaulon polystachyum, was investigated. Compound 1 displayed a higher scavenging activity on DPPH (72%) and ABTS (89%), at 100 ug/mL, than 2 and 3. In the non-enzymatic system of O2- generation, compound 1 scavenged (46%) superoxide radicals at a scavenging concentration (SC50) of 100 ug/mL. In addition, 1 inhibited 82% uric acid formation at 100 ug/mL, while allopurinol, employed as positive control, displayed 93% inhibition at the same concentration. The antioxidant ability of 1 is dose-dependant and apparently its OH group on C-6 is a structural requirement for the observed activity. A synergistic scavenging action of a ternary mixture (ratio 1:8:1) of 1, 2 and 3 was also observed.