Betalain profile, content and antioxidant capacity of red beetroot dependent on the genotype and root part

Abstract

Betalain profile and content by HPLC–TOF-MS/MS method and antioxidant capacity by four in vitro assays in thirteen varieties and root parts of red beet were determined. Red beetroot tissues contained thirty betalains, constituting of eighteen betacyanins and twelve betaxanthins. Among the betalains identified, betanin and isobetanin (betacyanins) and vulgaxanthin I (betaxanthins) were predominant. In varieties and root parts, betalain contents were 10.26–17.15 mg/g dm and 7.20–17.24 mg/g dm, respectively, differing significantly across varieties and root parts (P < 0.05). Among the root parts, peel was noted for the highest betalain concentration. Red beetroot extracts scavenged radicals, and their antiradical potential differed significantly across varieties and root parts (P < 0.05). Additionally, red beetroot antioxidant capacity was positively and significantly correlated with betalain content (P < 0.05). This study demonstrates that red beetroot varieties have their own betalain fingerprint as well as specific antioxidant capacity, which are also dependent on root part.