Ergot sclerotia on wheat
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Ergot sclerotia on wheat. History of ergotism. Rye was not cultivated until the 5 th century AD. Ergot prefers to infect rye flowers. Ergotism was widespread during the Middle Ages, since rye grows easily even in poor soils.

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Ergot sclerotia on wheat

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Ergot sclerotia on wheat

Ergot sclerotia on wheat


History of ergotism

History of ergotism

  • Rye was not cultivated until the 5th century AD.

  • Ergot prefers to infect rye flowers.

  • Ergotism was widespread during the Middle Ages, since rye grows easily even in poor soils.

  • The first historically documented outbreak of ergotism was in 857 AD in the Rhine valley.

  • Ergot grows best in a damp climate like that in Germany or Northern France.

  • Ergot was so common that it was called “Holy Fire”.


History of ergotism1

History of ergotism

  • An order of monks was founded just to take care of ergotism sufferers, the Order of St. Anthony's.

  • Ergotism became known at “St. Anthony's Fire”.

  • Dr. Thuiller in 1670 was the first to recognize that the disease was caused by ergot.

  • Dr. Louis Tulasne showed in 1853 that ergot was a fungus that infected rye and caused the disease.


The symptoms of ergotism

The symptoms of ergotism

  • Convulsive ergotism results in severe twisting of the body and neck in pain, together with shaking and trembling.

  • Gangrenous ergotism causes constriction of the blood flow in the extremities, which results in burning pain.

  • Fingers and toes die and they can even break off or drop off.

  • Both convulsive and gangrenous ergotism can be associated with vivid hallucinations, physical and mental excitement, and disorientation.

  • All forms of ergotism have a relatively high mortality rate.


The life cycle of ergot

The life cycle of ergot

  • After the winter, the sclerotia sprout to produce mushroom-shaped stroma, which release spores, in the spring.

  • These spores infect rye flowers to form asexual spore-forming spacelia, which in turn release spores.

  • Bees then transfer the spores to other rye flowers, and these spores grow eventually to reform the sclerotia.

  • This is an example of “alternation of generations”.


Ergotism and the salem witch trials

Ergotism and the Salem Witch Trials

  • Ergotism may have caused the Salem Witch Trials—Linda Caporeal.

  • In December 1691, a number of girls in Salem, including the daughter of the minister, Samuel Parris, developed unusual behaviors, including convulsions, odd postures and strange gestures.

  • They accused several women of being witches.

  • The girls did not improve, and eventually more than 100 people were accused and imprisoned.

  • Twenty people were executed as witches.

  • The remainder were eventually released.


Ergotism and the salem witch trials1

Ergotism and the Salem Witch Trials

  • The summer of 1691 was especially wet.

  • Most people in Salem grew rye as a staple crop.

  • The symptoms developed as soon as the rye crop was used.

  • The affected girls were from families who had the wettest fields.

  • As soon as a new rye crop was used, the symptoms disappeared.


The last outbreak of ergotism

The last outbreak of ergotism

  • The most recent outbreak of ergotism may have occurred at Pont-St.-Esprit, France in 1951.

  • Hundreds of townspeople suddenly developed strange symptoms, including intense pain, complaints of feeling cold, and dementia, accompanied by vivid hallucinations.

  • The doctors found that wheat bread was the common food item.

  • It may have been mixed with contaminated rye flour.

  • It has been recently suggested that the CIA poisoned the townspeople with LSD.


Pont st esprit

Pont-St.-Esprit


Animals also get ergotism

Animals also get ergotism

  • Tall fescue, a pasture grass for grazing cattle, can be infested with a fungal endophyte.

  • Animals that eat infected grass can develop vasoconstriction and gangrene in ears and hooves.

  • Afflicted animals do not eat and gain weight, causing economic loss to farmers.


Chemistry of ergot

Chemistry of ergot

  • Chemists were very interested in the components of ergot.

  • Ergotamine was isolated in 1918 by Arthur Stoll.

  • Ergotamine was found to be a derivative of lysergic acid (lysis ergot ic acid) by Jacobs and Craig at Rockefeller.

  • Albert Hoffman started working on lysergic acid derivatives at Sandoz in the 1930's.

  • He prepared ergonovine as a hemostatic drug for obstetrics.


Chemistry of ergot1

O

N

N

O

O

C

H

H

N

O

H

3

C

H

C

H

3

3

O

N

O

N

H

H

N

N

H

H

Ergotamine

D-lysergic acid

Chemistry of ergot


Chemistry of ergot2

Chemistry of ergot

  • Hoffman prepared a series of lysergic acid derivatives to evaluate their activity.

  • Lysergic acid diethylamide (Lyserg-Saure-Diäthylamid in German, or LSD) was the 25th derivative.

  • In 1943, after handling LSD-25, Hoffman noticed he felt odd for several hours.

  • The next day, he purposefully ingested 250 μg of LSD to determine if the compound caused the effects.


Chemistry of ergot3

Chemistry of ergot

  • Hoffman felt very strong effects and decided to ride his bicycle home.

  • He called the doctor, thinking he was dying.

  • The doctor found only that his pupils were dilated but he was otherwise normal.

  • After a few hours, the effects subsided.

  • Sandoz began to market LSD as an aid for psychotherapy.

  • In 1965, they took it off the market due to negative publicity.


Chemistry of ergot4

O

H

H

N

N

H

N

2

C

H

C

H

C

H

3

3

3

O

N

O

N

O

N

H

H

H

N

N

N

H

H

H

Ergonovine

LSA-11

LSD-25

Chemistry of ergot


Ergot and headaches

Ergot and headaches

  • Hoffman prepared other lysergic acid derivatives with activity against migraine headaches.

  • Methysergide is a serotonin antagonist which is prophylactic for migraines.

  • Dihydroergotamine can be taken after a migraine has started.

  • LSD has also been reported by users to relieve migraine and cluster headaches, and is under investigation now.


Ergot and headaches1

O

H

O

H

H

N

H

N

C

H

C

H

3

O

N

3

O

N

H

H

N

N

H

C

H

3

Methergine

Methysergide

Ergot and headaches


Triptans for headache treatment

Triptans for headache treatment

  • Serotonin antagonists are useful to treat migraine headaches.

  • A class of serotonin antagonists has been designed to treat migraines—triptans.

  • Sumatriptan (Imitrex) was the first triptan to be developed.


Triptans

H

N

N

N

O

N

H

S

O

O

O

S

H

N

O

2

N

N

N

H

H

H

Eletriptan (Relpax)

Sumatriptan (Imitrex)

Frovatriptan (Frova)

Triptans


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