A Preliminary Study On The Chemical Constituents And Hepatoprotective Activity Of Wahlenbergia Marginata

Lanhuashen is the roots or herbs of Wahlenbergia marginata(Campanulaceae).This medicinal plant is useful in clinic for the treatment of heptatis, but there is no report about its hepatoprotective activity.The objective of this study is to explore the active components of W. marginata and to investigate the effect of its aqueous methanol extract against acute liver injury of mice. The whole plant of W. marginata was extracted by aqueous methanol(80%)at room temperature, and the concentrate was freeze-dried to afford a solid extract. An acute liver injury model of mice induced by Concanavalin A was established.The model mice were given bifendatatum and the extract of W. marginata respectively.The ALT /AST in blood serum were determined,and the morphology changes of hepatic tissue were observed by HE. The results showed that the extract of W. marginata reduced the activity of ALT /AST in blood serum of acute liver injury of mice, and relieved the damage of liver pathological tissue.In order to find out the active components, the water-soluble part of the extract was studied primarily, and nine compounds were obtained by repeated column chromatography over silica gel, RP-C18, MCI and Sephadex LH-20. Their structures were elucidated on the basis of extensive spectral analysis including 1D and 2D NMR spectrum, as well as comparison with literature data. Compound 1 was elucidated to be a new compound and named wahlenoside D. The known compounds were identified as demethyl syringin(2), 3,5-dihydroxyphenethyl alcohol-3-O-β-D-glucopyranoside(3), farobin B(4), isovitexin(5), rutin(6), 3’-methoxy-5,7-dihydroxyflavone-6-C-β-D-boivinose-4’-O-β-D-glucopyranoside(7) and isovitexin2’’-O-rhamnoside(8),in which, compounds 3,4,5,6,7,8 were isolated from this plant for the first time.Finally, The whole plant of W.marginata was extracted by five different dissolvent(including methanol, 80% methanol, ethanol,80% ethanol and water). The groups of methanol, 80% methanol, ethanol and 80% ethanol were extracted at room temperature. The group of water was extracted with boiling water.The study on protective effects of these five different concentrates on acute chemical liver injury in mice showed that the hepatoprotective activity of water group had remarkable results.Further more, the contents of compounds 1-3, 5 and 6 in these five different concentrates were detected by HPLC analysis, and the results displayed that wahlenoside D(1) and 3,5-dihydroxyphenethyl alcohol 3-O-β-D-glucopyranoside(3)have a higher level in water group,demethyl syringin(2) and isovitexin(6) also have high content.