Assessment of anti-inflammatory properties of ethyl acetate extract of Stachys schtschegleevii Sosn
چکیده
Background: Stachys schtschegleevii Sosn. (commonly known as "Poulk" and "Sonbeleh Arasbarani") and Stachys inflate Benth. ("Sonbeleh Arghavani") are most widely used for medicinal purposes. Stachys schtschegleevii Sosn.( Lamiaceae) is widespread in North West of Iran and have been used traditionally to treat infections, asthma, rheumatic and other inflammatory disorders. In the present studies the anti-inflammatory activity of hydro-alcoholic extracts of both flowering and sterile tops of S. schtschegleevii were investigated. Material and Methods: The methanolic extract of the sterile aerial parts was partitionated between chloroform, ethyl acetate and n-butanol. The column chromatography (CC) on silica gel was used to fractionate the ethyl acetate extract and the anti-inflammatory effects of each main fraction were evaluated by carrageenan-induced rat paw oedema assay. The reversed-phase preparative HPLC was used to isolate compounds from the active fractions and their structure (1-3) were elucidated by spectroscopic means. The ethyl acetate portion was fractionated into 11 major fractions. Results: the most prominent anti-inflammatory effect was observed with fractions 8 to 10 of the ethyl acetate portion. Fraction 8 abolished considerably the mean maximal responses of inflammation from 87.00آ±3.5% in control to 61.10آ±7.2% (p<0.001) and 62.10آ±3.6% (p<0.001) in 15 and 30 mg/kg fraction-treated groups, respectively. Preparative-HPLC analyses of fractions 5 and 8-10 led to the isolation and identification of three major compounds, chrysoeriol 7-O-?-[6"-(p? coumaroyl)]-glucoside (1), apigenin 7-O-?-[6"-(p? coumaroyl)]-glucoside (2), and acteoside (3). Conclusion: It seems that caffeic acid derivatives such as acteoside may be implicated in anti-inflammatory effect of Stachys schetschegleevii Sosn.