Isolation of a new flavonoid from Prasium majus L. with evaluation of its potential biological activities

In line with the importance of Prasium majus L. (Lamiaciatae) in traditional medicine as a calming and sedative remedy, the present study was designed to reveal its chemical constituents and bioactivity potentials. Thus, after extraction and fractionation of the plant material, the obtained butanol fraction (BPm) was subjected to conventional chromatographic separation of its constituents in addition to LC-MS/MS evaluation versus some authentic standards. The study resulted in the isolation and characterisation of 8 compounds, including one new chrysoeriol derivative, majusiode (1). Structural elucidation of all isolated compounds was based on detailed investigation of their spectral data (NMR (1 & 2D), ESI-MS, IR and UV-Vis). HPLC-MS/MS analysis versus authentic samples lead to the detection of 31 constituents, including all 8 isolated compounds. The new compound (1) showed moderate AChE inhibition power (IC₅₀: 163.3 ± 3.4 µg/mL) as compared to the positive control galanthamine (91.4 ± 5.2 µg/mL) and moderate DPPH^•/ABTS^•+ scavenging power.