Page 15 - phytochemistry general program

NaOH .1
.2
Disadvantages:.
Non volatile. .3

Unsuitable for ester alkaloids, phenolic alk., also in presence of fatty matters.

Extraction with water miscible organic solvent (alcohol)

Alk. salts, alk. bases as well as alk. N-oxides and quaternary alkaloids can be
extracted with Ethanol & Methanol.

Extraction with dilute aquous acid (acidulated H2O) .4
In this method the powdered drug is heated with dilute acid (1-2%) then cool,

filter → crude alk. extract.

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:

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

Precipitation

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