Abstract
Pyrrolizidine alkaloids and their corresponding pyrrolizidine alkaloid-N-oxides are
secondary plant constituents that became the subject of public concern due to their
hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. In contrast to the well-established
analytical separation and detection methods, only a few studies have investigated
the extraction of pyrrolizidine alkaloids/pyrrolizidine alkaloid-N-oxides from plant
material. In this study, we have applied pressurized liquid extraction with the aim
of evaluating the effect of various parameters on the recovery of pyrrolizidine alkaloids.
The nature of the modifier (various acids, NH3) added to the aqueous extraction solvent, its concentration (1 or 5%), and the temperature
(50 – 125 °C) were systematically varied. To analyse a wide range of structurally
different pyrrolizidine alkaloids, Jacobaea vulgaris (syn. Senecio jacobaea), Tussilago farfara, and Symphytum officinale were included. Pyrrolizidine alkaloids were quantified by HPLC-MS/MS and the results
obtained by pressurised liquid extraction were compared with the amount of pyrrolizidine
alkaloids determined by an official reference method. Using this approach, increased
rates of recovery were obtained for J. vulgaris (up to 174.4%), T. farfara (up to 156.5%), and S. officinale (up to 288.7%). Hence, pressurised liquid extraction was found to be a promising
strategy for the complete and automated extraction of pyrrolizidine alkaloids, which
could advantageously replace other time- and solvent-consuming extraction methods.
Key words
pyrrolizidine alkaloids -
Symphytum officinale
-
Tussilago farfara
-
Senecio jacobaea
-
Jacobaea vulgaris
- pressurised liquid extraction - Boraginaceae - Asteraceae
