Anthocyanin occurrence in the root peels, petioles and flowers of red radish (Raphanus sativus L.)

Three novel acylated pelargonidin 3-sophoroside-5-glucosides were isolated from the root peels, petioles and flowers of red radish, Raphanus sativus ‘Cherry Mate’, in addition to five known anthocyanins namely, pelargonidin 3-sophoroside-5-glucoside, pelargonidin 3-[2-(glucosyl)-6-(trans-p-coumaroyl)-glucoside]-5-glucoside, pelargonidin 3-[2-(glucosyl)-6-(trans-feruloyl)-glucoside]-5-glucoside, pelargonidin 3-[2-(glucosyl)-6-(trans-p-coumaroyl)-glucoside]-5-(6-malonylglucoside) and pelargonidin 3-[2-(glucosyl)-6-(trans-feruloyl)-glucoside]-5-(6-malonylglucoside). The structures of three new acylated anthocyanins were shown to be pelargonidin 3-O-[2-O-(β-d-glucopyranosyl)-6-O-(trans-caffeoyl)-β-d-glucopyranoside]-5-O-(6-O-malonyl-β-d-glucopyranoside), its demalonyl derivative, and pelargonidin 3-O-[2-O-(β-d-glucopyranosyl)-6-O-(cis-p-coumaroyl)-β-d-glucopyranoside]-5-O-(6-O-malonyl-β-d-glucopyranoside). These pigments were the main components present not only in the root but also in the petioles and flowers of red radish. p-Coumaroyl anthocyanins were the main pigments found in the root, petioles and flowers. Although the trans-p-coumaroyl form was abundant in all three plant organs, its cis form was present in very low amount within the root but in large amount in the flowers and petioles.