LC-ESI-MS quali-quantitative determination of phenolic constituents in different parts of wild and cultivated Astragalus gombiformis.

High-performance liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) profiling of the MeOH extract of Astragalus gombiformis Pomel (Fabaceae) aerial parts guided the isolation of seven phenolic compounds among which 7-methylquercetin 3-O-α-l-rhamnopyranosyl-(1→2)-β-D-galactopyranoside (2) and 7-methylquercetin 3-O-α-L-rhamnopyranosyl-(1→2)-[6-O-(3-hydroxy-3-methylglutaryl)-β-D-galactopyranoside] (7) whose structures were elucidated by NMR and ESI-MS experiments. The radical scavenging activities of isolated compounds were investigated, by using the TEAC assay. Furthermore quantitative analyses were performed by LC-ESI-MS and applied to the comparative profiling of different parts (aerial parts, leaves and stems) of cultivated and wild A. gombiformis samples, confirming the interest of these compounds as markers of the species. Finally, a Principal Component Analysis was carried out in order to highlight the differences between different parts of cultivated and wild plants.