Metabolomics analysis of Vernonia Schreb: aiming chemotaxonomic purposes

Abstract

The Asteraceae are one of the largest family of plants, represeting about 10% of world's flora; it is caracterized by ability to produce secondary metabolites with high structural diversity. Within the Asteraceae stand out the tribe Vernonieae. The Vernonieae are a pantropical tribe and most of the species are assembled in the large genus Vernonia (sensu Baker). It is distributed widely in tropical and subtropical regions of America, Africa and Asia and it is chemically characterized by the presence of sesquiterpene lactones and flavonoids (flavones and flavonols). Over the years, several taxonomic classifications have been proposed to genus Vernonia, however there is not a consensus between the researchers. According to the traditional classification, the genus Vernonia includes more than 1000 species (sensu Baker) and it is divided in sections and subsections. In a recent classification, these species have been segregated into new genera (sensu Robinson), restricting the genus Vernonia exclusively to North America. Metabolite fingerprinting provides a detailed insight of secondary metabolites in an organism under certain conditions; so it is possible the determination of metabolic differences in samples using statistical tools. Thus, current techniques of metabolomics approaches associated with multivariate analyses issue as a potential chemotaxonomic tool. This study aims to analyze species of the genus Vernonia (sensu baker) using untargeted metabolomics approaches with the intention to clarify taxonomical classifications. These studies will be performed by obtainig metabolite fingerprinting, employing UHPLC-UV(DAD)-MS (Orbitrap), followed by multivariate analyses methods and phytochemical characterization. (AU)