Further research on chemotaxonomy of paeonol and analogs in Paeonia (Ranunculaceae)

In this paper, the paeonol, paeoniflorin and their analogs were analyzed in the roots of 14 species and 2 subspecies of Paeonia L. The existence and content of these compounds were discussed in three sections, sect. Moutan, sect. Paeonia and sect. Onaepia. In sect. Moutan, paeonol and its analogs were high in content in all species. In sect. Paeonia, low content of paeonol and its analogs were found in plants of four taxa, P. lactiflora, P. anomala ssp. veitchii, P. mairei and P. intermedia. None of these compounds was found in sect. Onaepia. Paeonol has a simple structure and is distributed widely in plant; its decrease and loss may be the result of evolution. Therefore, it is deduced that the relationship among the three sections of Paeonia might be that woody sect. Moutan is the more primitive and derived from the ancestor of Paeonia first. For the herbaceous sections, sect. Paeonia is more closely related to sect. Moutan than to sect. Onaepia. In sect. Moutan, there are less paeonol and its analogs in the species of subsect. Vaginata than in those of subsect. Delavayanae. Thus, the former may be considered more advanced. In sect. Paeonia, the taxa with minor content of paeonol and its analogs are diploid except P. mairei. Among them, P. lactiflora and P. anomala ssp. veitchii are relatively primitive by morphology. None of paeonol and its analogs was detected in the species with specialized form.