ABSTRACT
Six anthocyanins were isolated from the flowers of the Nagai line of Iris ensata Thunb. They were identified as petunidin and malvidin 3-O-beta-[(4"'-Z-p-coumaroyl-alpha-rhamnopyranosyl)-(1-->6)-beta-glucopyranoside]-5-O-beta-glucopyranosides (1 and 3) and their E-forms (2 and 4), and petunidin and malvidin 3-O-rutinoside-5-O-glucosides (5 and 6). Though the E-form of petunidin 3-O-[(4"'-p-coumaroylrhamnosyl)-(1-->6)-glucoside]-5-O-glucoside has been reported, its Z-form was found for the first time. The presence of Z- and E-forms of malvidin 3-O-[(4'''-p-coumaroylrhamnosyl)-(1-->6)-glucoside]-5-O-glucoside is also reported for the first time. Fifty-one cultivars of Nagai line and their wild form (I. ensata var. spontanea) were divided into four anthocyanin patterns, i.e. 1) the presence of 1-4, 2) the presence of 2 and 4, 3) the presence of 5 and 6, and 4) no anthocyanin.