Ergot

Synonyms: Ergot of Rye, Rye ergot, Secale cornutum, Ergota

Biological source:

Botanical name:Claviceps purpurea

Part used: dried sclerotium

Family: Clavicipitaceae

Botanical name of rye: Secale cereale

Family of rye: Graminae

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Geographical source:

Commercially cultivated in Czech, Slovak, Germania, Hungary and Switzerland.

• Life cycle
• Honey dew stage or Asexual stage
• The ovary of the rye plant gets infected by ascospores carried by wind or insects where ascospores germinate forming filamentous hyphae. The hyphae forms a soft mass of tissue over the surface of ovary known as mycelium. The mycelium secrets a viscous and sugary fluid called honey dew. At this stage hyphal strands produce asexual spores called conidiospore which remain suspended in the honey dew. Honey dew attracts ants and other insects which carry the conidiospores to other plants so to spread the disease.
• Sclerotium stage
• In this stage, hyphae penetrates deeper parts of ovary and finally replace the entire tissue.
• Ascospore stage
• Any ergot not collected falls to the ground falls to the ground and in next spring puts out number of stalked projections called stromata. These have globular head and the inner region has number of flask shaped pockets known as perithecia. Each perithecium contain sacs or asci which contain eight ascospores. These ascospore infect the young rye plant in the spring.

Macroscopical features

• Color: dark or violet black
• Odor: characteristic
• Taste: unpleasant
• Shape: sub cylindrical, slightly curved
• Size: 1-4 cm long,2-7 mm broad
• Other features: tapering at both ends, has longitudinal furrows sometimes cracks. Fractured surface shows outer dark layer and whitish or pinkish central zone of pseudoparenchyma.

Microscopical features

• Outermost layer is made up of thin flattened polygonal cells of purple to dark brown in color. Inner part is made up of pseudoparenchymatous cells composed of chitin.
• Central region contains mycelial cells with highly refractive walls which are round or oval and contains fixed oil.
• Slcerotium does not contain starch, calcium oxalate crystal
• Cellulose and lignin also absent

Chemical constituents

A number of alkaloids have been isolated from Ergot. On the basis of water solubility, they can be divided as:

Pharmacological action / Uses

• Mainly used as source of Ergot alkaloids.
• Ergometrine is oxytocic and produces stimulation of uterine muscles, also used for prevention and treatment of postpartum hemorrhage.
• Ergotamine is mainly used for the treatment of migraine.