11 March 2019

Lycorine - is making daffodils inedible

Natural toxin

Lycorine is a toxic natural alkaloid produced by most species of Amaryllidaceae family, such as Boophone, Clivia, Crinum, Galanthus, Haemanthus, Hymenocallis, Leucojum the cultivated bush lily (Clivia miniata), surprise lilies (Lycoris) and daffodils (Narcissus).

Structure of lycorine. Click image for interactive 3D-model

The Amaryllidaceae are a widespread in tropical to subtropical areas of the world as well as in many ornamental garden plants and vegetables. The plant family exclusively synthesized hundreds of alkaloids. Their fundamental molecular structure of Lycorine and derivatives is a ring system derives from L-phenylalanine and L-tyrosine. A single nitrogen atom, which is secondary, tertiary or even quaternary, is characteristic for these alkaloids. Lycorine (C16H17NO4) is an indolizidine alkaloid that is 3,12-didehydrogalanthan substituted by hydroxy groups at positions and 2 and a methylenedioxy group across positions 9 and 10.

Daffodil in Amaryllidaceae family is a common name for a family of plants called Narcissus. In the spring and early summer, Daffodil is a popular ornamental plant for community parks, personal gardens or as cut flowers. Lycorine is found in all parts of the plant particular in the bulbs. The daffodil is the source for many accidental poisonings since the bulbs look so similar to onions and may be misused in cooking. Eating any part of the plant can cause symptoms such as nausea, vomiting, abdominal pain, and diarrhea. It can be fatal if enough of the plant is ingested.

Lycorine is a cholinesterase or acetylcholinesterase (AChE) inhibitor. A cholinesterase inhibitor suppresses the action of acetylcholinesterase, thus affect potent neurotoxins, causing excessive salivation, eye-watering and followed by muscle spasms. In addition, depending on the amount consumed, Lycorine can produce intense gastrointestinal irritation, loss of appetite, low blood pressure, headaches, central nervous system depression.

CAS: 476-28-8
Molecular Weight: 287.315 g/mol
Smiles: C1CN2CC3=CC4=C(C=C3C5C2C1=CC(C5O)O)OCO4

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