Phytochemical characterization and biological activities of a hydroalcoholic extract obtained from the aerial parts of Matthiola incana (L.) R.Br. subsp. incana (Brassicaceae) growing wild in Sicily (Italy)

This study aimed to characterize the phenolic and the volatile constituents and to establish the antioxidant potential and the toxicity of a hydroalcoholic extract obtained from the leaves and flower buds of Matthiola incana (L.) R. Br. subsp. incana growing wild in Sicily (Italy). By HPLC-PDA/ESI-MS analysis twelve phenolics (two phenolic acid derivatives and ten flavonoids) were identified, eight out of them reported for the first time; luteolin-glucoside was the main (57.07 mg/g ± 0.87% RSD). By SPME-GC-MS forty-seven volatile constituents were fully characterized, and dimethyl trisulphide turned out to be the most abundant one (33.24%). The extract showed moderate activity both in the DPPH and in the reducing power assays (IC50 = 2.32  0.24 mg/mL; ASE/mL = 12.29  0.42); it did not inhibit the lipid peroxidation, whereas it was found to possess good chelating properties reaching approximately 90% activity at the highest tested dose. Moreover, the extract protected growth and survival from H2O2-induced oxidative stress in Escherichia coli. Finally, the extract resulted non-toxic versus Artemia salina (LC50 > 1000 µg/mL). These findings increase the knowledge of M. incana subsp. incana and they could be helpful to a chemosystematic distinguishing of this subspecies also demonstrating that the aerial parts represent a safe source of antioxidants.