1. ____________________________________________________________________
NAME : Shachi Vasudev Ratnaparkhi
ROLL NO. .: 61 SEMESTER : 8th SEM. (Final year)
SUBJECT : Advanced Instrumentation Techniques
TOPIC : Extraction Techniques
COLLEGE : SBSPM B-pharmacy College ,Ambajogai.
___________________________________________________________________
2. EXTRACTION TECHNIQUE’S
• Definition :
Extraction involves the separation of medicinally active portions
of animal or plant tissues from the inactive components through
the use of selective solvents.
• Extraction methods can be classified as Follows:
1. Solid – liquid extraction
2. Liquid-Liquid Extraction
3.
4. Principle :
• Extraction is a technique used in chemical or biochemical
processes to separate two or more different compounds (solid or
liquid) based on their relative solubility's in two different
immiscible liquid slovents (this usually applies for liquid-liquid
extraction).
• Extraction is the treatment of the plant or animal tissues with
solvent, whereby the medicinally active constituents are dissolved,
and most of the inert matter remains undissolved.
• The solvent used for extraction is known as Menstruum and the
inert insoluble material that remains after extraction is called Marc.
5. Solid-Liquid Extraction
• A solid is extracted by using a suitable solvent in four
different ways,
1. Maceration
2. Percolation
3. Continues extraction by using Soxhelt apparatus .
4. Devotion
6. 1 . Maceration:
• In this process, the whole or coarsely powdered crude drug is placed
in a stoppered container with the solvent and allowed to stand at
room temperature for a period of at least 3 days with frequent
agitation until the soluble matter has dissolved
• The mixture then is strained, the marc (the damp solid material) is
pressed, and the combined liquids are clarified by filtration or
decantation after standing.
• Limitations :
1. Maceration may not extract the samples completely in some cases
bacause. Of cold conditions
2. In this method , solvent used in the soaking process play a critical
role .
7.
8. 2. Decoction :
• In this process, the crude drug is boiled in a specified volume of
water for a defined time; it is then cooled and strained or filtered
• .This procedure is suitable for extracting water-soluble, heat stable
constituents.
• The starting ratio of crude drug to water is fixed, e.g. 1:4 or 1:16;
the volume is then brought down to one-fourth its original volume
by boiling during the extraction procedure.
• Then, the concentrated extract is filtered and used as such or
processed further.
10. 3. Percolation:
• Organized vegetable drug is taken in a suitably powdered form.
• Uniform moistening of the powdered vegetable drugs with
menstruum for a period of 4 hours in a separable vessel
(Imbibition).
• Packed evenly into the percolator. A piece of filter paper is placed
on surface followed by a layer of clean sand so that top layers of
drugs are not disturbed.
• Sufficient menstruum is poured over the drug slowly and evenly to
saturate it, keeping the tap at bottom open for passing of occluded
gas to pass out.
• Sufficient menstruum is also added to maintain a small layerabove
the drug and allowed to stand for 24 hours.
11. • After maceration, the outlet is opened and solvent is percolated at a control
rate with continuous addition of fresh volume.075% of the volume of the
finished product is collected.
• Marc is pressed and expressed liquid is added to the percolate giving 80%
to 90% of the final volume.
12. 4 .Hot Continuous Extraction (Soxhlet)
• In this method, the finely ground crude drug is placed in a porous
bag or "thimble" made of strong filter paper, of the Soxhlet
apparatus.
• The extracting solvent in flask is heated, and its vapors condense
in condenser. The condensed extractant drips into the thimble
containing the crude drug and extracts it by contact.
• When the level of liquid in chamber rises to the top of siphon
tube, the liquid contents of chamber falls from siphon into flask.
• This process is continuous and is carried out until a drop of
solvent from the siphon tube does not leave residue when
evaporated.The advantage of this method, compared to previously
