The first polyhydroxylated pyrrolizidine alkaloid with a hydroxymethyl group at C-3 was isolated from pods of Alexa leiopetala (Leguminosae) and designated alexine 1. The Australian legume Castanospermum australe is also known to produce the same structural type of pyrrolizidines. There are reports of the isolation of australine (7a-epi-alexine) 2, 1-epi-australine 3, 3-epi-australine 4, and 7-...

The atypical, non-toxic pyrrolizidine alkaloid tussilagin and its isomers have been found in only a few plants of the Asteraceae (Roeder et al., 1981,1984; Passreiter et al., 1992; Roeder et al., 1993; Sener and Etgun, 1996; Wernery et al., 1997; Passreiter, 1998). Their possible biosynthetic precursor pyrrolidine-2-acetic acid and its methylester were isolated and identi"ed together with the p...

The effect of a single (% LDs0) dose (65 mg/kg body weight) of pyrrolizidine alkaloid isolated from Senecio jacobaea on liver microsome mixed function oxidase activity in rats was studied. Within 1 hr of dosing, there was a decline (P<.05) in the pyrrole production rate in vitro from pyrrolizidine alkaloid. At 24 hr, there was reduced (P<.01) activity of aminopyrine N-demethylase, and cytochrom...

The metabolism in vitro of pyrrolizidine alkaloids by microsomes from eight animal species was studied. The rates of pyrrole production ranged from high to low in the following order: male hamster > male rabbit > male mouse > male rat > beef steer > beef bull female rat > wether lamb > male chicken male Japanese quail. With the exception of the rabbit and chicken, there appeared to be a direct ...

Plant-derived pyrrolizidine alkaloids play an important role in the biology of the salt marsh moth, Estigmene acrea (Lepidoptera: Arctiidae). They are phagostimulants for larvae and they stimulate the growth and development of adult male androconial organs called coremata. In this study, we have shown that the pyrrolizidine alkaloid monocrotaline N-oxide (MNO) fed to larvae also affects the cou...

In 1967 Kay et al postulated that some cases of unexplained pulmonary hypertension might be due to the ingestion of drugs or other toxic substances.' This concept, later termed dietary pulmonary hypertension,23 was advanced following the observation that the oral administration to rats of the pyrrolizidine alkaloid monocrotaline produced severe pulmonary hypertension.' There are no reports of p...