Metabolic Profiling ofEchinaceaGenotypes and a Test of Alternative Taxonomic Treatments

Abstract

The genus Echinacea is used as an herbal medicine to treat a variety of ailments. To better understand its potential chemical variation, 40 Echinacea accessions encompassing broad geographical and morphological diversity were evaluated under controlled conditions. Metabolites of roots from these accessions were analyzed by HPLC-photo diode array (HPLC-PDA), GC-MS, and multivariate statistical methods. In total, 43 lipophilic metabolites, including 24 unknown compounds, were detected. Weighted principal component analysis (WPCA) and clustering analysis of the levels of these metabolites across Echinacea accessions, based on Canberra distances, allowed us to test two alternative taxonomic treatments of the genus, with the further goal of facilitating accession identification. A widely used system developed by McGregor based primarily on morphological features was more congruent with the dendrogram generated from the lipophilic metabolite data than the system more recently developed by Binns et al. Our data support the hypothesis that Echinacea pallida is a diverse allopolyploid, incorporating the genomes of Echinacea simulata and another taxon, possibly Echinacea sanguinea. Finally, most recognized taxa of Echinacea can be identified by their distinct lipophilic metabolite fingerprints.

The effect of Echinacea preparations in three laboratory tests of anxiety: comparison with chlordiazepoxide

“…Discrepant findings with different extracts are likely explained by the fact that while the main constituents of various Echinacea species are essentially similar, the absolute amounts and the quantitative relationships between different constituents are subject to major variation (Kapteyn et al, 2002;Pellati et al, 2005;Percival, 2000;Perry et al, 2001;Wu et al, 2009). …”

“…Echinacea preparations contain a large number of different alkamydes, the structures of which are very similar to that of the endocannabinoid anandamide (Bauer and Remiger, 1989;Wu et al, 2009). Certain alkamydes behave as cannabinomimetics at both the cannabinoid CB1 and CB2 receptor, and inhibit the anandamide-degrading enzyme fatty acid amid hydrolase (FAAH) (Woelkart et al, 2005).…”

Subtracted Diversity Array Identifies Novel Molecular Markers Including Retrotransposons for Fingerprinting Echinacea Species

“…Nineteen of the 24 lines were selected from the germplasm collection of the U.S. National Plant Germplasm System maintained by the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS) ( Table 1 ) . These 19 lines were previously used in two independent studies [12], [21]. The other remaining lines were obtained from Botanical Resources Australia (Tasmania) and from verified specimens from a specialized plant nursery (The Diggers Club, Dromana Victoria) ( Table 1 ) .…”

“…Data obtained from a previous study [21] on metabolomic profiling of Echinacea genotypes was used for correlation analyses with the hybridization data. The relative abundance of 43 lipophilic metabolites in roots from 6-month-old plants was correlated with the normalized mean signal of the full feature set by performing Pearson bivariate correlations (SPSS version 17.0) and regression analysis (Microsoft Excel).…”

“…There is a recent study [21], in which metabolite profiles for 40 lines of Echinacea were generated by high performance liquid chromatography (HPLC). The lines analyzed represented a broad geographical and morphological background and were also used in the phylogenetic study described above [12].…”