Fractional analysis of dichloromethane extract of Scutellaria araxensis Grossh root and shoot by HPLC-PDA-ESI-MSn.

Scutellaria araxensis is a well-known ethnobotanical herb for the treatment of various diseases in Iranian traditional medicine. In this study, dichloromethanolic fraction of partitioned methanol root and shoot extract was analysed by silica gel column chromatography, thin layer chromatography and high-performance liquid chromatography combined with photodiode-array detector, and coupled to electrospray ionization with Q-Exactive Orbitrap mass spectrometry (HPLC-PDA-ESI-MSn) in positive ion mode. Metabolites were tentatively characterized by comparing their mass spectrometry spectra with those of bibliographic data. A total of 11 flavonoids were identified from different fractions. Results showed that root and shoot produced very similar flavone patterns characterized by the presence of baicalein, tricin, tenaxin I, tenaxin II, skullcapflavon II, chrysin, wogonin and isorhamnetin. Norwogonin and apigenin-7-glucoside were identified only from shoot. Remarkably, Tenaxin I, II, tricin, apigenin-7-glucoside and norwogonin were tentatively profiled as new compounds for the first time from S. araxensis formula.