The document discusses Soxhlet extraction, which is a method of extracting compounds from solids using liquid solvents. It involves placing the solid in a thimble or filter paper inside an extraction chamber, and continuously washing it with solvent heated to its boiling point. The solvent extracts the desired compounds, then collects in a receiving flask. Key steps include selecting an appropriate solvent, drying plant materials, setting up the apparatus, running the extraction for several hours, and recovering the extract by evaporating the solvent. Advantages are high efficiency and yield, while disadvantages include length of time and potential thermal degradation of compounds.

2.  Extraction definition
 Why we need for extraction??
 Collection
 Drying
 Soxhlet extraction history
 Parts
 Properties of solvents
 Types of solvents
 Procedure
 Advantages and disadvantages
 application

3.  Extraction is the method of removing
active constituents from a solid or
liquid by means of liquid solvent
 The separation of medicinally active
portions of plant or animal tissues
from the inactive or inert components
by using selective solvent
 The solvent used for extraction is
known as menstrum and the
remaining inert material that remains
after extraction is known as marc

4.  The purposes of standardized extraction procedure
for crude drugs are to attain the therapeutically
desired portion
 Also to eliminate the inert material by treatment
with a selective solvent known as menstrum
 Natural medicines are prepared using these
extracts

5.  The preparations popularly have been called as
gelanicals, named for galen
 He is the second century greek physician

6. PROTOCOL FOR
EXTRACTION

7.  The plant that we going to collect should
contain good medicinal properties
 Medicinal plant materials should be
collected during the appropriate season
or time period to ensure the best possible
quality of both source material and
finished product
 It is well known that the quantitative
concentration of biologically active
constituents varies with a stage of plant
growth and development
 After collection the medicinal plants are
subjected to appropiriate preliminary
processing to remove contaminants,
rodents ,pests, insects etc….

8.  Bark- cinnamon, cinchona
 Rhizomes – rhuberb, valerian, turmeric, ginger
 Root- ipecac, rauwolfia, gentian, aconite
 Leaves-senna, datura, belladona, digitalis,
 Flowers-rose,clove,saffronin
 Fruits-, capsicum, cardomum
 Seeds-almond, nux-vomica mustard

9.  By this process we can remove
moisture from plant material
 This process is done for preventing
the microorganisms growth
 Facilitating the grinding process
 Inhibiting of enzymes and
reactions which can convert some
of the plant constituents from
active to inactive state
 To stop the enzymatic process the
water content must be brought
down to about 10 percentage
 Now the dried plant material is
ready for soxhelet extraction

10. SOXHLET
EXTRACTION

11.  It was developed by Frant von soxhlet a German
chemist in 1879
 His focus is mainly on protein and sugar in milk
 So he develop this to know the fates in milk
 It can be used both on laboratory and industrial scale

13.  It should be highly selective for the compounds to be
extracted
 Not react with the extracted compound or with other
compounds in the plant material
 Should have low price
 Should be easily available
 Should not be harmless to man and the enviroinment

14.  Be completely volatile
 Should not nix up with water
 Should not have big capacity in relation to
extractive
 Should have the minimum viscosity
 The solvents should stored in a reagent bottle
to avoid the evaporation

15. SOLVENT BOILING POINT(⁰C) POLARITY
HEXANE 69 NON POLAR
HEPTANE 98 NON POLAR
PENTANE 36 NON POLAR
ISO-HEXANE 60 NON POLAR
OCTANE 126 NON POLAR
ETHANOL 79 POLAR
PROPANOL 97.15 POLAR
BUTANOL 116-118 POLAR
PENTANOL 138 SLIGHTLY POLAR
HEXANOL 157 NON POLAR
DICHOLOROMETHANE 40 SLIGHTLY POLAR
TOLUENE 111 NON POLAR

16.  A polar solvent is a liquid with molecules that
have a slight electrical charge due to its shape.
 For example, water is a molecule with one
oxygen and two hydrogen atoms.
 The two hydrogen atoms are not on opposite
sides of the oxygen, but rather at an angle
 EXAMPLE
 Ethanol, methanol, acetone etc …

17.  Non-polar solvents are liphophilic as they
dissolve non-polar substances such as oils, fats,
greases.
EXAMPLES
 Carbon tetra chloride
 Diethyl ether
 Hexane

18.  Grind the sample thoroughly and homogenously
 Weigh the sample using electronic weighing
balance

19.  Transfer the sample to the filter paper which is
made up of cellulose or thimble
 Pack it properly

20.  The round bottom flask is taken with the solvent
 Heating mantle is present to heat the solvent
 The siphon tube is fitted with the round bottom
flask
 Thimble is fitted inside the siphon tube
 At the top of the siphon arm connect the condenser
 In condenser the bottom one is for inlet the top one
is for outlet

21.  The solvent is heated at reflux
 As it boils its vapors rise up and are condensed
by a condenser
 The condensed solvent then fills up in the
thimble
 After it fills with enough solvent it
automatically siphons back down into the
container of organic solvent
 This process takes place over and over again
until the material to be extracted from the solid
in the thimble is extracted

22.  The process may continue for 6 to 8 hours or
more than that
 The water flow to the apparatus should be in a
continues proper manner
 Otherwise it leads to the damage of the
apparatus

23.  Soxhlet extraction method is suitable for extraction of
alkaloids from powdered plant material with the
help of organic solvents
 Actually alkaloids and their respective salts are
soluble in alcohol like methanol, ethanol,
isopropanol
 The extraction with total alkaloids with alcohol is
highly recommended because of its maximum
efficiency and economical viability

24.  the most widely used water-immiscible solvents
for the extraction of alkaloids are chloroform,
diethyl ether and isopropyl ether.
 a few other specific organic solvents, namely
ethylene chloride, carbon tetrachloride and
benzene may be employed with an evident
advantage for certain specific alkaloids.
 chloroform is regarded as the best water-
immiscible solvent for a broad-spectrum of
alkaloids .
 But, Chloroform is not suitable for the extraction
of quaternary alkaloids

25.  The suitable temperature of extraction
improves the diffusion ratio of tannins into the
solvent and the circulation of the solvent.
 Fifty percent ethanol gives the highest extract
yield of tannins from herbal plants .
 Soxhlet extraction with water as a solvent is
also the best method for gallic and ellagic acid
extractions.
 The solvents such as water or ethanol-water
mixtures are used for the extraction of the
active hydrolysable tannins

26.  When the evaporation temperature of the
solvents is high, thermal destruction of tannins
can happen
 So sometimes the soxhlet extraction is
restricted

27.  Glycoside drugs are extracted using suitable
water solvent and alcoholic solvents like
ethanol, propanol, hexanol, pentanol etc..
 After extraction the the glycosidal drugs are
treat with lead acetate to precipitate the
tannin

28.  The crude drugs have their biological
activity mainely due to active chemical
constituents
 These constituent may be soluble in
different polar, semipolar, nonpolar
solvent
 Total soluble constituents of the drug in
any particular solvent or mixture of
solvents can be called as its extractive
value

29.  This method determines the amount of active
constituents in given amount of medicinal
plant material or crude drug when extracted
with solvents
 It also helps to indicate the nature of chemical
constituents present in the drug
 Also helpful to identify the adulteration

30.  First we have to remove the solvent using
distillation method
 Pour the concentrated extract in a pre weighted
petridish
 Evaporate the solvent completely and take the
final weight of the petridish
 The difference between the initial weight and final
weight of the petridish gives the extractive value
of the solvent

31. W2-W1
―――――― 1OO
W3
W2 Initial weight of the petridish
W1 final weight of the petridish
W3 weight of the plant powder

32. DISTILLATION METHOD EXTRACTION METHOD
Distillation is the method of purifying
a liquid by a process of heating and
cooling
Extraction is the action of extracting
something. Ecspecially using efforts
and force
Uses the difference between boiling
point and chemical components in a
mixture
Uses the different solubility and
boiling point
Can done for only liquid phase
mixtures
Can be done for liquid and solid
phase mixtures

33.  Soxhlet extraction is advantageous in a way
that less solvent is needed for yielding more
concentrated products
 The extraction is continuous until complete
exhaustion of the drug
 Can be used for small scale and large scale
productions
 High efficient extraction and complete
extraction is done

34.  It is a lengthy process
 The process is not suitable for thermoliabe
substance
 The process is restricted to pure boiling
solvents or to azeotrope
 An azeotrope is a mixture of two or more
liquids in such a ratio that it its composition
cannot be changed by simple distillation
 Azeotrope are also called as constant boiling
mixtures.

35.  The extracts obtained may be for
use as medicinal agent in the form
of tinctures and fluid extracts
 It may be further processed to be
incorporated in any dosage forms
such as tablets or capsules

36.  It is the most useful apparatus for solid liquid
extraction in various fields such as
Pharmaceutics, foodstuffs
 Now a days soxhlet apparatus is still common
and widely used as a reference and standard
method in many laboratories for the
extraction of secondary metabolites from
various plant materials or crude drugs

37.  Biren shah, A.k seth., text book of pharmacognosy
and phytochemistry,
 The soxhlet extractor
explained.(https://www.google.com/amp/oleoresi
ns.melbia.com/priciples of soxhlet extraction and
experimental setup html/amp)
 https://www.sciencedirect.com topics
 https://www.ncbi.nil.nih.gov pmc
 http://www.sciencedirect.com/soxhlet-extraction