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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

3- Purification (defatting, removal of other constituents): by
a. Pb acetate: precipitate non-glycosides (resins, pigments, proteins).
b. Petroleum ether: for de-fatting and removing lipids.

4- Extraction and Fractionation.

• dilute alcohol is the best choice for extracting most glycosides.

• Isolation of the glycosides from the purified aqueous solution, by crystallization
or chromatography (Silica, column chromatography).

Qualitative determination of glycosides:

• Tests For aglycone (genin): depending on the chemical nature of the genin
(aglycone):

Tests For sugar (glycone): examples

The hydrolyzing enzymes: The specificity of their action is often applied for the
identification of the sugar moieties of glycosides, or even for the identification of
the glycoside as a whole. For Example:

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