Screening of monoterpene indole alkaloids in six Rauwolfia species by ultra‐high performance liquid chromatography orbitrap velos pro mass spectrometer

Abstract

AbstractMonoterpene indole alkaloids have gained significant interest due to their important medicinal properties and unique skeletal characteristics. There is an urgent need to develop simple, fast and suitable method for identification and characterization of monoterpene indole alkaloids in plant extracts. Therefore, ajmaline, ajmalicine and serpentine were analyzed by direct infusion into electrospray ionization source under high‐resolution mass spectrometric conditions using orbitrap velos pro mass spectrometer in collision‐induced dissociation mode. The diagnostic fragment ions were identified and established fragmentation pathways on the basis of multistage mass spectrometry. Multistage mass spectrometric analysis showed C‐ring cleavage in ajmaline and ajmalicine whereas in serpentine E‐ring cleavage took place by retro Diels Alder. Optimized multistage mass spectrometric conditions for ajmaline, ajmalicine and serpentine were applied along with developed ultra high performance liquid chromatography with orbitrap velos pro multistage mass spectrometry method for ammoniacal chloroform root extracts of six Rauwolfia species. In total, 17 alkaloids were identified and characterized on the basis of their chromatographic, mass spectrometric and multistage mass spectrometric analysis in the ammoniacal chloroform root extracts of six Rauwolfia species. This method could be used to speed up dereplication of these bioactive monoterpene indole alkaloids in extracts.