DETERMINATION OF ANTHOCYANINS, FLAVONOIDS AND PHENOLIC-ACIDS IN POTATOES - I - COLORED CULTIVARS OF SOLANUM-TUBEROSUM L

The major anthocyanins, flavonoids and phenolic acids in the tubers (s kin and flesh), flowers and leaves of 26 cultivars of Solanum tuberosu m L with coloured skins and/or flesh have been identified and quantifi ed using analytical HPLC. Red tubers contained mostly pelagonidin-3-(p -coumaroyl-rutinoside)-5-glucoside (200-2000 mu g g(-1) FW) plus lesse r amounts of peonidin-3-(p-coumaroyl-rutinoside)-5-glucoside (20-400 m u g g(-1) FW). Light to medium purple tubers contained petunidin-3-(p- coumaroyl-rutinoside)-5-glucoside (1000-2000 mu g g(-1) FW) plus small amounts of malvidin-3-(p-coumaroyl-rutinoside)-5-glucoside (20-200 mu g g(-1) FW) whilst dark purple-black tubers contained similar levels of petunidin-3-(p-coumaroyl-rutinoside)-5-glucoside together with much higher concentrations of malvidin-3-(p-coumaroyl-rutinoside)-5-glucos ide (2000-5000 mu g g(-1) FW). Tuber flesh also contained chlorogenic acid (30-900 mu g g(-1) FW) and other phenolic acids plus low concentr ations of flavonoids (0-30 mu g g(-1) FW). Tuber skins showed much hig her levels (1000-4000 mu g g(-1) FW) of chlorogenic acid. The major an thocyanins in flowers were present as the rutinosides or other glycosi des of pelargonidin, petunidin and malvidin whilst glycosides of cyani din and delphinidin were found in some flowers, together with many of the same phenolic acids as found in tubers. The commonest flavonoids i ncluded rutin, kaempferol-3-rutinoside and two quercetin-rhamnose-gluc osides. Flowers and leaves contained higher concentrations of flavonoi ds which fell into two patterns, with some cultivars containing high c oncentrations of quercetin-3-glycosides, whilst others had much lower concentrations. (C) 1998 SCI.