An analytical approach to profile steroidal saponins in food supplements: The case of Ruscus aculeatus

Ruscus aculeatus L. (Liliaceae) rhizomes are well-known constituents of a great number of food supplements utilized to prevent the microcirculation diseases. Since steroidal saponins are the main class of chemical compounds isolated from rhizomes and roots of R. aculeatus, and they can be considered the active phytochemicals of R. aculeatus commercial products, an analytical method based on high-performance liquid chromatography coupled to electrospray positive ionisation tandem ion trap mass spectrometry (HPLC–ESI/ITMS2) was applied in order to obtain a prompt and easy detection of these metabolites in the butanolic extract of R. aculeatus rhizomes. According to this approach, 17 steroidal saponins belonging to furostanol and spirostanol classes were identified. Subsequently, on the basis of the on-line screening, all compounds were isolated, by reversed-phase HPLC–UV and/or HPLC–IR, and their structures were unambiguously confirmed by 1D and 2D NMR experiments, highlighting the occurrence in R. aculeatus rhizomes of six furostanol saponins never reported before.