Field survey of Glycyrrhiza plants in central Asia (2). Characterization of phenolics and their variation in the leaves of Glycyrrhiza plants collected in Kazakhstan.

A new prenylated flavanone, licoleafol, and a new prenylated dihydrostilbene, uralstilbene, together with four known compounds, 8-dimethylallyleriodictyol, sophoraflavanone B, gancaonin R, and 6-dimethylallyleriodictyol, were isolated from the leaves of Glycyrrhiza uralensis collected in Kazakhstan. HPLC analysis of the leaves of Glycyrrhiza plants collected in Kazakhstan showed that both G. uralensis-specific and Glycyrrhiza glabra-specific compounds were detected in the leaves of the morphologically intermediate-type plants, suggesting that the intermediate-type plant is a hybrid of G. glabra and G. uralensis. In addition, HPLC profiles of leaf extracts from offspring of intermediate-type plants were divided into the three types: the G. uralensis type, G. glabra type, and the intermediate type. From these results, it appears likely that the intermediate-type plant back-crosses with G. glabra and G. uralensis to generate a G. glabra-type plant and a G. uralensis-type plant, respectively.