Determination of Selected Biologically Active Substances in Dietary Supplements and the Adaptogenic Herb Rhaponticum carthamoides Using HPLC–MS/MS

Abstract R haponticum carthamoides (Willd.) Iljin, widely known as maral root, is an adaptogenic herb that has been used in traditional medicine for centuries. Several different classes of compounds were identified in R. carthamoides , including phytosteroids, flavonoids, and phenolic acids. Nowadays, R. carthamoides is available on the market in many forms, such as dried root, milled plant, capsules, and tinctures. This study presents the development and optimisation of four HPLC–MS/MS methods for the determination of 37 selected bioactive compounds in both plant and dietary supplements. Due to insufficient ionisation at the ion source, stigmasterol and ß-sitosterol required derivatization, which was developed and optimised using 2-fluoro-1-methylpyridinium p -toluenesulfonate. The dried plant samples were extracted with 60% ethanol or tert -butyl methyl ether. The results showed that chlorogenic acid and 20-hydroxyecdysone were the most abundant. To reduce the dimensionality of the obtained data, factor analysis was applied. Based on the distribution of selected compounds, four clusters were observed: tinctures, seeds, root, and shoot systems of the herb. Using the developed methods, selected bioactive compounds in the herb and dietary supplements were successfully quantified, and their distribution in different organs of R. carthamoides was clarified.