Phenolic Composition of Inflorescences of Carduus nutans L.

Carduus nutans L. (Compositae) has been extensively used for medicinal purposes. As other representatives of the genus it is implemented in the treatment of liver disorders and used as diuretic and digestive agent. Previous studies have determined the predominant classes of secondary metabolites in Carduus species. Among the major representatives of their extracts flavonoids, phenolic acids, coumarins, sterols and terpenes were identified. The antiradical capacity of three extracts assessed in the DPPH test revealed the highest radical scavenging properties of methanol extract (the EC50 618 +/- 10.03 mu g/mL) and based on these results it was selected for phenolic content determination. (TPC=61.49 mg/g). To understand better the induced pharmacological effects of the plant the aim of the study was to determine the composition of the methanol extract from the inflorescences of C. nutans and to study their phenolic composition. In order to determine the composition in a more efficient way, the crude extract was fractionated and subjected to hydrolyses. As a result more than twenty phenolic acids and flavonoids were identified in the extract and fractions by HPLC-DAD and/or HPLC-ESI-TOF-MS. The total extract was later subjected to fractionation by centrifugal partition chromatography using the Arizona system composed of hexane/ethyl acetate/methanol/water (0.7 : 4 : 0.8 : 4 v/v/v/v) to produce fractions enriched in flavonoids that are of high pharmacological significance.