Identification of saponins from sugar beet (Beta vulgaris) by low and high-resolution HPLC–MS/MS

•A total of 26 triterpene saponins were characterized in sugar beets using two HPLC–MS systems.•Seventeen of the triterpene saponins had not been previously detected in sugar beets.•Seven new compounds were reported in B. vulgaris L. roots for the first time.•2 groups of isomers were reported in sugar beet for the first time.•This is the first report of the identification of two new aglycone structures in sugar beets. We profiled triterpene saponins from the roots of sugar beet Beta vulgaris L. cultivars Huzar and Boryna using reversed-phase liquid chromatography combined with negative-ion electrospray ionization quadrupole mass spectrometry. We tentatively identified 26 triterpene saponins, including 17 that had not been detected previously in this plant species and 7 saponins that were tentatively identified as new compounds. All observed compounds were glycosides of five different aglycones, of which gypsogenin and norhederagenin are reported for the first time in sugar beet. Thirteen of the saponins detected in sugar beet roots were substituted with dioxolane-type (4 saponins) or acetal-type (9 saponins) dicarboxylic acids. Among the 26 detected saponins, we identified 2 groups of isomers distinguished using high-resolution mass measurements that were detected only in the Huzar cultivar of sugar beet.