Print E-mail

Alkaloïds

  Ergotamine
Alkaloïds CAS N°
formula :
molecular mass:
colourless crystals :
Solubility:


Analysis :

LD50 (bw mice)

113-15-5
C33H35N5O5
581.66 g/mol
(mp = 212-214 °C)
Soluble in organic solvents,
insoluble in water

TLC, LC-FLD, LC-MS/MS

3 mg/kg (iv injection)
550 mg/kg (oral)

 

 

IN A FEW LINES :

Alkaloids are naturally occurring chemical compounds containing basic nitrogen atoms. The name derives from the word "alkaline". Alkaloids are produced by a large variety of organisms, including bacteria, fungi, plants and animals.


Many alkaloids are toxic to other organisms and have often pharmacological effects. Examples are the local anaesthetic and stimulant cocaine, the stimulant caffeine, nicotine, the analgesic morphine or the antimalarial drug quinine. Some alkaloids have a bitter taste.Alkaloïds


Ergot alkaloids are indole derivatives produced by several fungi and hence are mycotoxins. All species of the Claviceps genus, especially Claviceps purpurea, produce ergot alkaloids. Ergot is the name given to the hard black bodies formed by C. purpurea, which are the resting stage of the fungus and contain up to 40 different alkaloids.
Claviceps species infect many wild grasses and cereals, especially rice.
The ergot alkaloids are well known from their role in human poisoning throughout history. Epidemics of ergotism were common in Europe in the Middle Ages where it was known as "Holy Fire" or "St Anthony's Fire".
Today, ergotism has practically been eliminated as a human disease, but still can be a veterinary problem, particularly in cattle, horses, sheep, pigs and chicken. The alkaloids affect the central and sympathetic nervous systems, as well as immune and reproductive systems, resulting in muscle contractions, convulsions, changes in blood pressure, lowered immune response, reduced lactation and reproductive capabilities, hallucinations and gangrene of the extremities.
Ergot alkaloids are not transferred into cow milk.
The pharmacologically active ergot alkaloids are generally not found in prepared foods, as cleaning and milling remove the sclerotia, while the active ergot alkaloids are heat labile. The main ergot alkaloids are ergotamine, ergocornine, ergocristine, ergocryptine, ergometrine and agroclavine.

 

Pyrrolizidine alkaloids (PAs) are found in plants of widespread geographical distribution. Over 200 alkaloids have been identified in 300 plant species belonging to up to 13 families. It has been estimated that up to 3 % of the world flowering plants contain toxic PAs. To name just a few : Senecio jacobaea (Compositae), Crotalaria (Leguminosae) and Heliotropium (Boraginaceae).
PAs are esters of hydroxylated 1-methylpyrrolizidines. Poisoning has occurred through contamination of wheat. Milk and honey can be contaminated by PAs. PAs have been detected in medicinal plants as comfrey. There is a long history of toxicity in livestock caused by grazing on PA-containing plants.

 

Quinolizidine alkaloids are found in Lupinus and other genera of the Fabaceae. They cause mainly neurological effects in mammals.

 

Glycoalkaloids of Solanum. Glycoalkaloids (a combination of a sugar and an alkaloid) are commonly found in nightshade and also in potatoes (solanine, chaconine). A total glycoalkaloid content of max 200 mg/kg potato is often found in literature as the upper safety limit. Potato meals containing high levels of glycoalkaloids have produced effects in man on the gastro-intestinal tract and the nervous system, and even death.
In animals foetal malformations and foetal deaths are known.

Alkaloïds

NORMS AND LEGISLATION :

There are currently no regulations for individual ergot alkaloids in food. Only in Canada and Uruguay, ergot alkaloids in feed are regulated.

 

In Canada : guideline limits are 6 mg/kg in feed for swine, 3 mg/kg in feed for dairy cattle, sheep and horses and 9 mg/kg in feed for chicks.

 

Many countries have recommended or imposed maximum limits for the percentage of ergots allowed in cereals. A maximum limit of 1000 mg/kg ergot bodies (0.1 % w/w) has been introduced for feed products containing ungrounded cereals. In USA and Canada there is a maximum of 300 mg ergot per kg grain.

 

The European Union Scientific Panel on Contaminants in the Food Chain of the EFSA (European Food Safety Authority) has reviewed the ergot issue in 2005 (EFSA J 225: 1-27).


ROLE OF CODA-CERVA :

CODA-CERVA has a scientific interest in alkaloids in feed and food. Analytical methods based on LC-MS/MS will be developed.

 

SCIENTISTS RESPONSIBLE FOR THIS TOPIC :

Alfons Callebaut