4-Nerolidylcatechol from Pothomorphe Spp. Scavanges Peroxyl Radicals and Inhibits Fe(II)-Dependent DNA Damage

Abstract

The total reactive antioxidant potential (TRAP) and total antioxidant reactivity (TAR) of 4-nerolidylcatechol (4-NC) and methanolic extracts of Pothomorphe umbellata and P.peltata were determined by monitoring the intensity of luminol enhanced chemiluminescence by peroxyl radicals derived from thermolysis of 2,2′-azobis(2-amidinopropane). The highest antioxidant potential was measured in the extract of P. umbellata (TRAP = 97.2 µM) while the highest reactivity was observed in the extract of P.peltata (TAR = 5.0 µM), measured as equivalents of Trolox concentration. These results were higher than those obtained for 4-NC (TRAP = 33.6 µM, TAR = 4.9 µM). DNA sugar damage induced by Fe(II) salts was also used to determine the capacity of 4-NC to suppress hydroxyl radical-mediated degradation of DNA. Calculated IC₅₀ values for 4-NC and catechin, used as a standard, were 25 and 17 µM, respectively.