Page 137 - PG 504-theoretical notes-phyto-1-2024-2025..

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

3. Enzymatic hydrolysis:

➢ The glycoside-bearing plants contain at the same time the specific enzymes, that are
contained in different cells other than those containing the glycosides.

➢ Thus, glycosides are not acted upon by the coexisting enzymes within the intact plant
tissues.

➢ However, upon processing (powdering, grinding, extraction etc.) the cell walls are
destroyed and the glycosides are acted upon by the enzymes.

Therefore, it is necessary to destroy (or deactivate) the enzymes which are
present before attempting to isolate glycosidal constituents.

▪ Specific in action.

E.g: Glycosides with rhamnose moiety: Rhamnase.

o Exceptions for enzyme

Emulsin hydrolyses any of the β-glycosides

Myrosin hydrolyses all sulfur-containing glycosides

Nomenclature

1. Trivial name:

in--ending, indicates the source of the glycoside.

Example: digitoxin from Digitalis and salicin from Salix

2- Systematic names: chemical name:

(α- or β-) (D or L) (sugar-ose) oside.

118