Anthocyanin, carotenoid content, and antioxidant values in native south American potato cultivars

Tubers of 38 native potato cultivars of different taxonomic groups from South America were analyzed to determine the total anthocyanins, total carotenoids, and antioxidant values. Total anthocyanin ranged from zero to 23 mg cyanidin equivalents/400 g fresh weight (FW). Total carotenoid ranged from 38 to 2020 mu g zeaxanthin equivalents/100 g FW. Oxygen radical absorbance capacity (ORAC) was measured for the anthocyanin (hydrophilic) and carotenoid (lipophilic) extracts. The hydrophilic ORAC ranged from 333 to 1408 mu M Trolox equivalents/100 g FW. The lipophilic ORAC ranged from 4.7 to 30 nM alpha-tocopherol equivalents/100 g FW. The cultivars consisted of 23 diploids, seven triploids, and eight tetraploids. Total carotenoids was negatively correlated with total anthocyanins. Total anthocyanins was correlated with hydrophilic ORAC. Among clones with less than 2 mg cyanidin equivalents/100 g FW, total carotenoid and lipophilic ORAC were correlated, but this was not true for analysis of all 38 clones. Although total anthocyanins or hydrophilic ORAC values reported here were not outside of the ranges found in North American and other breeding materials, total carotenoids and lipophilic ORACs are higher than previously reported, suggesting that native cultivars of South America with high levels of total carotenoids and high lipophilic ORAC are a unique germplasm source for introgression of these traits into specific potato cultivars outside the center of origin.