Page 14 - Pharmd general phytochemistry I-Final2024_LEUCTERS

2. SCARIFICTION AND EXPRESSION METHOD

Used for volatile oils:
 Cannot be distilled without decomposition (sensitive to heat,
thermolabile).
 Found in large amount in oil – glands in the outer surface in the
peel (rind). Generally, they are obtained by expressing the rind of
the fresh fruit. ex. oil of orange and lemon.
a) The sponge method:

-The citrus fruit is washed, cut into halves. and the juicy part is removed.
The rind is turned inside out and squeezed. Secretory glands rupture and
the oil is collected by means of the sponge. When the sponge becomes
saturated, it is squeezed in a vessel and the oily layer is separated from
the aqueous layer.

b) écuelle à piquer method (Scarification):
- The entire fruits are rotated in metal pins with sharp projections just long
enough to penetrate the epidermis puncturing oil cells to exudate the oil.

3. EXTRACTION WITH SOLVENT

Used for volatile oils:
 Containing labile constituents (sensitive to heat).
 Present in extremely small quantities ex. in the flowers of jasmine,
violet, roses (Perfumes).

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