Abstract

Comparison of Polyphenol Content and Antioxidant Capacity of Colored Potato Tubers, Pomegranate and Blueberries

Diganta Kalita and Sastry S Jayanty

Dietary antioxidants from fruits and vegetables play an important role in preventing free radical-induced oxidative damage to lipids, proteins, and nucleic acids. Potato tubers with purple- and red-colored flesh contain high levels of phenolics and anthocyanins, as do pomegranates and blueberries. The present study evaluates the antioxidant potential of colored-flesh potato tubers in comparison with polyphenol-rich fruits, blueberries and pomegranate juice. The ranges of total phenolics (TP), total anthocyanins (TA), and total flavonoids (TF) were (4482 – 11189 μg/g), (1889 – 6289 μg/g), and (140-503 μg/g), respectively. The potential antioxidant capacities of the potato tubers were similar to that of pomegranate and blueberry. High correlations of TP, TA, and TF with antioxidant activity, such as ORAC, ABTS, and DPPH (r=0.95, 0.93, and 0.80 for TP; r=0.93, 0.96, and 0.54 for TA; r=0.80, 0.91, and 0.70 for TF), were found for the materials tested. The total antioxidant activity values per serving size of baked red and purple potatoes, blueberries, and pomegranate juice were also found to have comparable ranges.