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138 CHAPTER 7

In another form, gangrenous ergotism, the blood cap-
illaries contract, causing oxygen starvation and serious
damage in the tissues. The ergot alkaloids have some
important medical uses, to relieve some types of
migraine and to control hemorrhaging after childbirth
(Keller & Tudzynski 2002). They can also be abused

• the indole nucleus of one of the ergot alkaloids,
  ergotamine, is lysergic acid, and this can be altered
  chemically to produce the hallucinogenic drug, LSD
  (lysergic acid diethylamide; Fig. 7.18). We return to this
  subject in Chapter 13.

In contrast to the ergot alkaloids, the health hazard
posed by the many fungi that grow inconspicuously
on stored food and feedstuffs was only recognized in
relatively recent times. In the 1950s there were outbreaks

of canine hepatitis (associated with certain types of dog

food) and of liver cancer in farmed rainbow trout, asso-

ciated with cottonseed meal in the fish food. In 1959,

100,000 young turkeys died in Britain after being fed

on fungus-contaminated cottonseed meal. The cause

was traced to a new type of toxin, termed aflatoxins,

some of which are among the most potent known

carcinogens.

Aflatoxins

Aflatoxins are produced mainly by Aspergillus flavus

(hence the name aflatoxin) and A. parasiticus, both

of which are common in tropical and subtropical

conditions. They grow on the root systems and crop

Fig. 7.17(a) Ergots (sclerotia) of Claviceps purpurea, produced in place of the grains of a ryegrass plant (Loliumsp.).
(b) Longitudinal section through the small, stalked fruiting body of Claviceps, which releases ascospores from peri-
thecia (p) embedded in the surface of the fruiting body.

CH 3

HN

O

N

N

N

H

H

N

H

O

OH

H

H

O O

CH 3

CH 2

Lysergic acid dimethylamide (LSD)

CH 3

N

H

H

N

O

HN

CH 2 .CH 3

CH 2 .CH 3

Ergotamine

Fig. 7.18Structure of the ergot alkaloid ergotamine, and its derivative lysergic acid dimethylamide (LSD).

(a) (b)

p

p