Iridoids and flavonoids from the aerial parts of Gentiana asclepiadea L. with anti-inflammatory and analgesic activities

Abstract

Using various chromatographic methods, seven compounds, including two secoiridoid glycosides; depressine (1) and gentiopicroside (2), one iridoid glycoside; loganic acid (3), two flavone-C-glycosides; isoorientin (4) and isovitexin (5), one xanthone-C-glycoside, mangiferin (6) as well as a nucleoside; adenosine (7) were isolated from the MeOH extract prepared from the aerial parts of Gentiana asclepiadea L. Their structures were elucidated unambiguously by spectroscopic methods such as 1D and 2D NMR as well as HRESIMS. The anti-inflammatory and analgesic activities of the isolated compounds were also evaluated in vitro. Among the tested compounds, 1, 2, and 4 showed potent anti-inflammatory activity through both nitrite and IL-6 pathways at 200 µM. Besides, compound 1 exhibited the highest decrease in PGE2 level, with a higher inhibition rate compared to positive control indomethacin.