Lamiaceae is a family of plants belonging to the Eudicot clade of Angiosperms, comprising 236 genera and 7534 species. These plants are spread all over the world growing on rocky, calcareous and sandy soils in hot and temperate climates which makes them perfectly suitable for the Mediterranean habitat. The overall phylogenetic tree inserts this family among the most derived ones (1). In this work, we present a study on the evolution of some Lamiaceae species according to phytochemical data using secondary metabolites such as iridoids as metabolic markers. We focused our attention on two sub-families and their genera: Ajugoideae (Ajuga and Teucrium) and Lamioideae (Lamium, Melittis and Stachys). Our scope was to ascertain if the phylogeny of Lamiaceae based on phytochemical data is in agreement with that deriving from DNA sequencing which represents the traditional way of building phylogenetic trees. The basilar concept of phytochemical evolution is that the more oxidized is the compound, the more evolved is that biogenetic pathway. Previous works (1,2) placed Ajugoideae as an early branching subfamily in Lamiaceae (with Teucrium diverging before Ajuga) while Lamioideae are indeed the most derived ones with Lamium, Melittis, and Stachys as following grades. During our phytochemical analysis, conducted by means of classical Column Chromatography for the separation procedure of the ethanolic crude extracts and by means of NMR Spectroscopy and MS spectrometry for the identification of the natural compounds present in the samples, we evidenced the presence of several iridoids. Among these, the chemotaxonomic markers of the family were present but also some which are actually more typical of other families. Moreover we found iridoids which are biosynthesized according to different pathways thus providing a more accurate and general view of the family. These results allowed us to take the first steps into the formulation of a new phylogenetic tree concerning the studied genera of Lamiaceae.
Study on the evolution of some Lamiaceae based upon phytochemistry
F. Maggi;
2016-01-01
Abstract
Lamiaceae is a family of plants belonging to the Eudicot clade of Angiosperms, comprising 236 genera and 7534 species. These plants are spread all over the world growing on rocky, calcareous and sandy soils in hot and temperate climates which makes them perfectly suitable for the Mediterranean habitat. The overall phylogenetic tree inserts this family among the most derived ones (1). In this work, we present a study on the evolution of some Lamiaceae species according to phytochemical data using secondary metabolites such as iridoids as metabolic markers. We focused our attention on two sub-families and their genera: Ajugoideae (Ajuga and Teucrium) and Lamioideae (Lamium, Melittis and Stachys). Our scope was to ascertain if the phylogeny of Lamiaceae based on phytochemical data is in agreement with that deriving from DNA sequencing which represents the traditional way of building phylogenetic trees. The basilar concept of phytochemical evolution is that the more oxidized is the compound, the more evolved is that biogenetic pathway. Previous works (1,2) placed Ajugoideae as an early branching subfamily in Lamiaceae (with Teucrium diverging before Ajuga) while Lamioideae are indeed the most derived ones with Lamium, Melittis, and Stachys as following grades. During our phytochemical analysis, conducted by means of classical Column Chromatography for the separation procedure of the ethanolic crude extracts and by means of NMR Spectroscopy and MS spectrometry for the identification of the natural compounds present in the samples, we evidenced the presence of several iridoids. Among these, the chemotaxonomic markers of the family were present but also some which are actually more typical of other families. Moreover we found iridoids which are biosynthesized according to different pathways thus providing a more accurate and general view of the family. These results allowed us to take the first steps into the formulation of a new phylogenetic tree concerning the studied genera of Lamiaceae.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
