Analysis of prenylflavonoids from aerial parts of Epimedium grandiflorum and dietary supplements using HPTLC, UHPLC-PDA and UHPLC-QToF along with chemometric tools to differentiate Epimedium species

Abstract

An UHPLC method was developed for the determination of 15 prenylflavonoids from aerial parts of Epimedium grandiflorum and related species (Berberidaceae). The separation was achieved using a reverse phased column and water/acetonitrile gradient as a mobile phase at a temperature of 40°C. The developed analytical method was validated for linearity, limits of detection (LOD) and limits of quantification (LOQ), stability and repeatability. The LOD and LOQ were found to be in the range from 0.1-0.5 μg/mL and 0.3–1 μg/mL, respectively. The wavelength used for quantification with the photodiode array detector was 269 nm. The total content of 15 prenylflavonoids was 9.1–20.6 mg/g for E. grandiflorum (except for sample #2899 and #20862), 5.6–35.4 mg/g for E. brevicornu and 10.8–30.5 mg/g for E. sagittatum. Twenty dietary supplements contained in the range from 0.1 to 81.7 mg/day. The developed method is simple, rapid and especially suitable for quality assessment of E. grandiflorum and dietary supplements containing E. grandiflorum. Liquid chromatography quadrupole time-of-flight-mass spectrometry (LC-QToF) is described for the identification and confirmation of compounds in plant samples and dietary supplements. This technique is also used for chemical profiling of Epimedium samples. This method involved the use of protonated ions in the positive ion mode and deprotonated ions in the negative ion mode with extracted ion chromatogram (EIC). Chemometric analytical tools for visualizing the plant and commercial samples quality were used for discriminating between Epimedium species and dietary supplements with regards to the relative content or presence of components. A HPTLC method was also developed for the fast chemical fingerprint analysis of Epimedium species.