Source
Lycorine is found in different species of Amaryllidaceae which include flowers and bulbs of daffodil, snowdrop (Galanthus) or spider lily (Lycoris). Lycorine is the most frequent alkaloid of Amaryllidaceae.[2]
A 2014 research paper suggested that the earliest diversification of the Amaryllidaceae likely occurred in North Africa and the Iberian Peninsula. Furthermore, the study concluded that the biosynthetic pathway responsible for lycorine production is the oldest among the various toxin synthesis pathways found within the Amaryllidaceae.[3]
Mechanism of action
There is currently very little known about the mechanism of action of lycorine, although there have been some tentative hypotheses advanced concerning the metabolism of the alkaloid, based on experiments carried out upon beagle dogs.[4]
Lycorine inhibits protein synthesis,[5] and may inhibit ascorbic acid biosynthesis, although studies on the latter are controversial and inconclusive. Presently, it serves some interest in the study of certain yeasts, the principal organism on which lycorine is tested.[6]
It is known that lycorine weakly inhibits acetylcholinesterase (AChE) and ascorbic acid biosynthesis.[7] The IC50 of lycorine was found to vary between the different species it can be found in, but a common deduction from the experiments on lycorine was that it had some effect on inhibiting AChE.[8]
Lycorine is a potent inhibitor of multiple human cancer cell lines.[9][10]
Poisoning by lycorine most often occurs through the ingestion of daffodil bulbs.
Daffodil bulbs are sometimes confused with onions or other Allium species, leading to accidental poisoning.[11]
In a study on beagle dogs, the first sign of nausea was observed at as little of a dose of 0.5 mg/kg and occurred within a 2.5 hour span. The effective dose to induce emesis in the dogs was seen to be 2.0 mg/kg and lasted no longer than 2.5 hours after administration.[12]
Symptoms of lycorine exposure include nausea,[13] vomiting with diarrhea, and convulsions.[14]
