Page 13 - Phytochemistry 2 (06-PG 605)

Purification of Alkaloidal Extracts

After distillation of the solvent used for extraction of alkaloids from powered plants
the conc. alk. ext. (or crude alk. extract) is further purified by either:

1. Precipitation ( two methods).
2. Partition process (acid-base purification)
3. Chromatography.

Precipitation

II. Precipitation of alkaloids with alkaloids precipitating reagents
Examples of the alkaloidal pptating agent e.g. Mayer’s, wagner’s, dragendorff’s
The insoluble alk-complex with these reagents are purified by :

1. Filtration.
2. Decomposition of the insoluble alk-complex to get the free alkaloid

(regeneration).
3. Extraction of the free alk. base with suitable organic solvent.

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