Free Radical-Scavenging Properties and Antioxidant Activity of Fractions from Cranberry Products
Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace containing antho- cyanins, water-soluble and apolar phenolic compounds, respectively. Compounds with close polarities were collected to obtain between three and four fractions from each juice or extract. The cranberry phenols are good free radical-scav- engers, but they were less efficient at inhibiting the lipid peroxidation. Of all the samples tested, the intermediate pola- rity fraction of extract rich in apolar phenolic compounds of fruit presented the highest antiradical activity while the most hydrophobic fractions of the anthocyanin-rich extract from fruit and pomace appeared to be the most efficient at inhibiting the lipid peroxidation. The antioxidant or pro-oxidant activity of fractions increased with the concentration. The phenol polarity and the technological process to manufacture cranberry juice can influence the antioxidant and an- tiradical activities of fractions.