“Extraction of Alkaloids”
Extraction methods vary with the scale and purpose of the operation and with the raw material. Following general methods are adopted for extraction of alkaloids.
Process “A”
The powdered material is moistened with water and mixed with lime, which combines with acids, tannins and other phenolic substances and set free the alkaloids, if they exist in the plant as salts.
Extraction is carried with organic solvent such as ether and petroleum spirit.
The concentrated organic liquid is then shaken with aqueous acid and allowed to separate.
Alkaloid salts are now in the aqueous liquid, while many impurities remain behind in the organic solvent.
Process “B”:
The powdered material is extracted with water or aqueous alcohol containing dilute acid. Pigment and other unwanted material are removed by shaking with chloroform or other organic solvents. The free alkaloids are then precipitated by the addition of excess of sodium bicarbonate or ammonia and separated by filtration or by extraction with organic solvent.
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