Identification of new flavonoid glycosides and flavonoid profiles to characterize rocket leafy salads (Eruca vesicaria and Diplotaxis tenuifolia).

"Rocket" is a collective name used to term some species within the Eruca and Diplotaxis genera, whose leaves are characterized by a more or less pungent taste. Different approaches have been carried out to differentiate both genera that have similar leaf morphologies. Following our research in flavonoid profiling of the Brassicaceae family using high-performance liquid chromatography/ultraviolet-diode array detection/electrospray ionization mass spectroemtry, we have investigated Eruca vesicaria and Diplotaxis tenuifolia leaf samples as new ingredients of fresh salads. The MS/MS study allowed the identification of new naturally occurring quercetin mono- and diacyl-tri-O-glucosides and the elucidation of the flavonoid glycosylation and acylation patterns. Important differences between flavonoid profiles of E. vesicaria and D. tenuifolia were observed. E. vesicaria contained kaempferol derivatives as principal compounds whereas D. tenuifolia instead accumulated quercetin derivatives. The exhaustive study of the profiling of these species could help further studies concerning the bioavailability of these flavonoids for epidemiological or clinical intervention studies because these species have considerable potential as healthy leafy salads because of the bioactive phytochemicals.