Phytochemical investigation of Scabiosa sicula guided by a preliminary HPLC-ESIMSn profiling

Abstract

The genus Scabiosa (Caprifoliaceae) is represented by 80 species, widely used as medicinal plants for their positive effects on human diseases. On the basis of the interesting biological activity shown by Scabiosa spp., the phytochemical investigation of Scabiosa sicula L., never investigated before, was carried out. An initial LC-MS profile of the MeOH extract of S. sicula whole plant guided the isolation of 34 compounds, of which the structures were unambiguously elucidated by NMR analysis as phenolic compounds and triterpene saponins, among which eight undescribed compounds. Moreover, the total phenolic content of S. sicula methanol extract has been evaluated. On the basis of the pharmacological activities reported for Scabiosa species the antioxidant activity of the methanol extract was tested by TEAC and DPPH assays. Finally, the α-glucosidase inhibitory activity of the methanol extract was assayed, showing an IC₅₀ value (49 μg/mL) comparable to that exerted by acarbose (90 μg/mL), used as positive control.

Keywords: Antioxidant activity; Caprifoliaceae; LC-MS; Scabiosa sicula; Triterpene-type saponins; α-glucosidase inhibitory activity.