Free flavonoid aglycones as markers of parentage in Mentha aquatica, M-citrata, M-spicata and M. x piperita

External lipophilic methylated flavonoids have been extracted from dried le aves of Mentha aquatica, M. spicata, M. x piperita and M. citrata. After se paration and purification, twenty flavonoids have been identified by means of spectrometric methods (UV, EIMS, H-1 NMR). The flavonoid patterns of the se species and hybrid support the view that M. x piperita may be a hybrid o f M. aquatica and M. spicata while a linalool-producing sample of M. citata may be considered a variety of M. aquatica. Cytological data agree with th e observed biochemical results. (C) 1999 Elsevier Science Ltd. All rights r eserved.