Extraction
involves the separation of medicinally active constituents of a plant or animal tissue from an inactive or inert component by using solvents and one of the standard extraction procedures
2. - Extraction
involves the separation of
medicinally active constituents of a
plant or animal tissue from an
inactive or inert component by
using solvents and one of the
standard extraction procedures.
9. -Generally ,we can classify extraction
methods into two types:
*cold methods
* Hot methods
10. Extraction by Cold Method:
(
طويلة لمدة النقع
)
التعطين
1) Maceration :
It is a process that includes soaking of
plant material with the solvent until
penetration of cellular structures take
place and the active constituent
softened and dissolved in the solvent .
(
25g plant+
12. *2) Percolation :
In this method , we are going to use special
apparatus that called percolator . The percolator
has a porous diaphragm at the bottom .The
procedure includes placing a powder plant
material in the percolator and start adding the
solvent from the upper end . While the solvent
going downward to extract as much as possible
the active constituent , then passing through the
diapharagm.
13. The plant material is much better to be soak by
the solvent a both ½ hours before starting the
procedure. The solvent used depend on the
active constituent .
The menstrum and the extract we got it called
percolate and the plant material left called mark
material
16. Hot Method of Extraction
1) Infusion
In this method , we have special container called
infusion pot .This method used for extraction of
volatile oils. The procedure involves :
*placing the plant material in the infusion pot then we
add the solvent , which is boiling water , and cover
with a heavy lid that contains sieves .
*addition of the solvent , leave it for a while to permit
the extraction of the active constituent. During that
time , the volatile oils evaporated with steam ,
deposited and condensed on the lid.
We take the solvent, which contains the active
constituent .
17. الغلي
2) Decoction :
In this method
*we place the powdered plant material in a container
then add the solvent and place the containeron source of
heat or direct flame (direct or indirect heating).
* Agitating until the active constituent dissolved in the
solvent
This method usually used for hard plant material like
bark, stem and roots, which contain many fibers .
*The solvent used depends on the active constituent and
the source of heat e.g.:
Chloroform and ether can not be used because we use a
direct source of heat . The active constituent should be
heat stable.
18.
19. 3) Digestion :
In this method , the plant material placed
together with the solvent and we apply a gentle
heat so that the solvent will increase its power
for extraction and this method used in cases
where moderately elevated temperature is
required .
21. soxhlet
Ordinary reflux
Consists from a round bottom
flask connected with extracting
chamber containing a thimble
and the extracting chamber
connected to the condenser.
Consists from a round
bottom flask connected
directly to a condenser
1
The plant material is placed in
the thimble separated from the
solvent.
The plant material is placed
together with the solvent in
the round bottom flask.
2
The extract does not require
filtration.
The extract require filtration.
3
The plant material not directly
exposed to heat
The plant material directly
exposed to heat
4