Pyrrolizidine Alkaloids in Adenostyles alliariae and A. glabra from the Austrian Alps.

The alkaloid content of Adenostyles alliariae and A. glabra (Asteraceae) has been evaluated. Both species contain toxic macrocyclic unsaturated pyrrolizidine alkaloids with seneciphylline as the main compound accounting for more than 90% of the alkaloid fraction in all above ground plant parts. Further alkaloids were spartioidine, acetyl-senciphylline and senecionine. Inflorescences showed the highest alkaloid contents with 21.1 and 13.4 mg/g in A. alliariae and A. glabra, respectively. Stems and leaves had 2-3 times lower contents. Therefore, these Adenostyles species must be considered as highly toxic plants.