Chemotaxonomy of Gentianopsis: Xanthones, C-glycosylflavonoids and carbohydrates

• Published in: Biochemical systematics and ecology 1982-01, Vol.10 (4), p.319-327
• Main Authors: Massias, M., Carbonnier, J., Molho, D.
• Format: Article
• Language: English
• Subjects: C-glycosylflavones, sugars; Gentianaceae; Gentianopsis, chemosystematic evolution; xanthones
• ISSN: 0305-1978; 1873-2925
• DOI: 10.1016/0305-1978(82)90006-0

In the genus Gentiana s.l. (Gentianaceae), the status of the section Crossopetalum Froel, is still very much debated. On Morphological grounds. Ma regarded this section as an independent genus which he called Gentianopsis. In this paper we discuss this proposal, taking into account chemotaxonomic data (xanthones, carbohydrates and C-glycosylflavones) arising from an examination of leaves and flowers of 13 species including the type-species Gentianopsis barbata. Isoscoparin, primeverose. 1,3,7- and 1,3,7,8- O-substituted xanthones were present in all species, while 1,3,5,8- O-substituted xanthones were absent. These criteria clearly differentiate the group from Gentianella (occurrence of 1,3,5,8- O-substituted xanthones, absence of 1,3,7- O-substituted xanthones, presence of swertisin, absence of primeverosel in which they were previously included. Furthermore, a comparison of Crossopetalum with two species belonging to Gentiana s.s. (the type G. lutea L. and G. orbicularis Schur.) discloses some analogy with respect to xanthone composition (only 1,3,7- or 1,3,7,8-substitution, respectively). However, the presence of gentianoise in Gentiana s.s., in contrast to its absence in Gentianopsis, indicates that the latter should be excluded from Gentiana. The assessment on morphological grounds of the validity of the genus Gentianopsis Ma is thus reinforced. The evolutionary signification of the chemical characters and the phyletic relationships of Gentianopsis with the other genera of the Gentianinae are discussed.