Abstract

Sensitive chromatographic methods were developed for the quantitative analysis of secondary metabolites in Hypericum perforatum (St. John's wort) and Rhodiola rosea (Golden root, rose root) extracts. Sample preparation methods were developed for plant, cell culture and biotransformation suspension matrixes. High performance liquid chromatography (HPLC) was used for the separation of analytes, and chromatographic data was acquired using photodiode array (PDA) detection or atmospheric pressure ionization mass spectrometry (API-MS). Ionization efficiencies with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) were compared under different conditions. Specific mass spectrometric detection methods such as multiple reaction monitoring (MRM) and selective ion monitoring (SIM) were utilized. For identification of known and new secondary metabolites in plant tissues, mass spectrometric methods with triple quadrupole and time-of-flight mass spectrometers were used together with one- and two-dimensional nuclear magnetic resonance spectroscopy (NMR).