Phenolic profiling of Rumex L. species by means of the LC-MS/MS

Rumex L. genus, traditionally known as the sorrels and the docks, is a genus that comprises about 200 species. Although native to Europe and Asia, nowadays it is introduced almost everywhere. They have use in traditional medicine as antiseptic and antidiuretic cures, whereas the roots of some Rumex species are used for its laxative, depurative and tonic properties. Sorrel is also often used in French cooking. Previous chemical studies have detected various constituents among which are flavonoids, anthraquinones and tannins. The objective of this work was to determine differences in overall phenolics composition of selected Rumex species: R. patientia L., R. acetosa L., R. acetosella L., R. crispus L, Rumex obtusifolius L. and Rumex balcanicus Rech. LC-MS/MS technique was used for quantitative analysis of 80% ethanolic extracts of aerial parts, roots, leaves, flowers and stems of selected Rumex species. Fourtyfive reference compounds from different phenolic classes were selected: benzoic acid derivatives, cinnamic acid derivatives, lignans, coumarins and flavonoids (flavonoid aglycons, flavonoid-O-glycosides and flavonoid-C-glycosides). Principal component analysis (PCA), a multivariate analysis technique, was employed for data analysis in order to evaluate a „phenolic profile“of investigated species. High content of hyperoside and isoquercitrine differentiates R. acetosa from other Rumex species. Abundant content of apigenin and cinaroside, as well as lower content od gallic acid, distinguish R. acetosella and R. acetosa samples from other investigated ones. High amount of rutin is determined in R. patientia species samples. This work showed significant quantitative and qualitative differences in “phanolic profile” of investigated species.