Page 191 - PG 504-theoretical notes-phyto-1-2024-2025..

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

2- Extraction method

➢ Extraction method is used for heat sensitive volatile oils or in case of presence of low
volatile oil content in plants.

➢ It is used mainly in production of flower perfume

a) Cold Fat Extraction or Enfleurage Method
It depend on the extraction of the oil using cold fat “lard”. Lard is thickly spread and a layer
of flowers is sprinkled to cover its top for 24 h, the flowers are then removed and replaced
by a fresh supply, up to several months, until the fat become saturated with the essential oil.

The flowers are removed and oil is recovered by extraction with absolute alcohol which is
distilled off under vacuum (Defleurage) . “e.g. Jasmine oil”.

b) Hot Fat Extraction or Maceration Method:
It depends on immersing the plant material in hot melted fat (lard or fixed oil) and rotated until
exhausted. The mixture is then squeezed and the process is repeated with fresh plant material
until a special concentration is reached. The perfume –containing fat (pomade) is allowed to
cool and then extracted with absolute alcohol.

Advantage: It is faster than enfleurage

c) Solvent Extraction
What are the requirements of the solvent used in extraction:
Organic solvents used for volatile oil extraction should be:
1. Volatile
2. Selective
3. Possesses low boiling point.
4. Inert
5. Water immiscible
6. Low price

Disadvantage: Low quality V.O. “Darker in colour due to extraction of some plant
pigments”.

3) Mechanical method

a) Expression “sponge Method”

• The essential oils of citrus fruits such as Orange, Lemon, Mandarin, Bergamot, and
Lime are extracted from their fruits using a method called expression. This is a simple
method in which the rind is squeezed to produce the essential oil. The oil is collected
by means of sponge until saturation, the sponge is then squeezed in a vessel to separate
the oil.

172