Antioxidant activity of ethanolic extracts from several asparagus cultivars

摘要

Three different methods (antiradical activity, inhibition of primary oxidation, and ferric reducing power) have been used to evaluate the antioxidant activity of eight different asparagus cultivars and byproducts: white and green asparagus from Alcal8 del Rfo (Guadalquivir Valley, Seville) and American hybrids, native spears, and their byproducts from Hu6tor-Tajar (Vega de Granada). The correlation between antioxiclant activity and total phenol content was studied. Six standards were also tested to validate the modified methods for antioxiclant activity determination. Results obtained for antiradical capacity and reducing power were very similar, and a high correlation with phenols was found (R >= 0.9 for both tests). Sample origin was an important factor, spears from Huetor-TaJar having higher values (ARC between 7 and 10 and P-R of 0.25-0.33) than those from Alcala del Rio (ARC 0.6-2 and PR of 0.05-0.07). Significant differences were found between spears with the same origin, suggesting that genetics are another factor to take into account. Asparagus inhibits lipid primary oxidation, but no correlation between the inhibition percentage and phenols was observed. Asparagus origin was the only factor that led to significant differences: samples from Huetor-TAjar had higher values (POIC between 18 and 32) than those from Alcala del Rfo (POIC of 5-9). Byproducts from the canning industry at Huretor-TAjar were also assayed for antioxidant activity; the results obtained suggested that byproducts could be considered as an excellent source of natural antioxiclants.