Phytochemical Profile of the Aerial Parts of Sedum sediforme and Anti-inflammatory Activity of Myricitrin

Abstract

The aim of this study was to investigate the phytochemical profile of the methanol extract of the aerial parts of Sedum sediforme and to identify its secondary metabolites. By means of chromatographic separation and enrichment of compounds, HPLC-ESI-MS, HRMS, 1D-, 2D- NMR and/or comparison with reference compounds, three triterpenes, two sterols, ten flavonoids and twelve phenolic compounds were identified, together with two new compounds, i.e. (2 R*, 3 R*)-5,7-dihydroxy-2,3-dimethyl-4-chromanone-7- O-ß-D-glucoside (27) and butan-2- O-rutinoside (28). Out of the 29 identified secondary metabolites, 18 are described as ingredients of S. sediforme herein for the first time. Furthermore, myricitrin, one of the major constituents, was tested for its ability to inhibit different enzymes within the arachidonic acid cascade in order to determine its anti-inflammatory properties. Whereas there was only either weak or no inhibition of the microsomal prostaglandin E2 synthase-1 (mPGES-1) and the soluble epoxide hydrolase (sEH), myricitrin showed strong inhibition of 5-lipoxygenase (5-LO), with an IC50 of 7.8 ± 0.2 μM.