Combined HPLC-DAD-MS, HPLC-MSn and NMR spectroscopy for quality control of plant extracts: The case of a commercial blend sold as dietary supplement

- HPLC-DAD-MS, HPLC-MSn and NMR analyses revealed the fraudulous content of a dietary supplement.
- Rauwolfia sp. alkaloids (ajmaline, reserpine) were found.
- Reserpine was in the therapeutic range and responsible for the collapses of the patients.