Antioxidant activity of Larrea divaricata Cav. extracts

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

Tucumán - Argentina

Congreso; XXV Annual Scientific Meeting of Tucuman Biology Society; 2008

Tucuman Biology Society (publicado en Bio Cell 33 (2))

Free radicals and non-stable species that react with biomolecules as proteins, nucleic acids, lipids and pigments are implicated in several  physiological and pathogenic processes such as aging, carcinogenesis, rheumatoid arthritis, artheriosclerosis and neurovegetatiove diseases. The damage on the DNA can be irreversible and consequently inheritable. Antioxidants are substances that can avoid these effects by neutralizing free radicals. The object of this work was to determine if ethanolic extracts of Larrea divaricata Cav (Ld) and its fungitoxic fraction (Fr B)  isolated by bioguided fractionation, have scavenging capacity on free radicals and reactive oxygen species (ROS). Their antiradical activity was evaluate by 1-1 diphenyl-2-picryl-hydrazyl (DPPH) leaching rate showing that IC50 was 14 and 27 µg PC (Phenolic Compounds).ml-1 of Ld and Fr B respectively against 7 and 40 µg.ml-1 of quercetin and BHT used as reference substances. Antioxidant activity was evaluated by heat induced oxidation in a ß-carotene and linoleic acid system. Antioxidant Activity Coefficient (AAC) at 120 min of BHT, quercetin, Ld and Fr B  were 918, 708, 666 and 351 respectively. Ld had higher scavenging capacity of superoxid anion than Fr B; their IC50 was 12 and 18 µg PC.ml-1. Ascorbic Acid IC50 used as control was 58 µg.ml-1 Our results demostrated that Larrea divaricata Cav is a potential source of natural antioxidant compounds suggesting that it could be useful in the treatment of different pathologies in which free radical production plays an important role.