2. Extraction
Extraction may be defined as 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
3. Theextract thusobtained, after standardization,
may beused asmedicinal agent
•assuch in theform of tinctures
•fluid extracts
•further processed to beincorporated in any
dosageform such astabletsand capsules
4. Choice of solvents
• Successful determination of biologically
activecompoundsdependson thetypeof
solvent used in theextraction procedure.
• Thechoiceof solvent isinfluenced by what is
intended with theextract.
5. Properties of a good solvent
in plant extractions
low toxicity,
easeof evaporation at low heat,
promotion of rapid physiologic absorption of
theextract,
preservativeaction,
inability to causetheextract to complex or
dissociate.
7. Steps Involved in the
Extraction of
Medicinal Plants
1. Sizereduction
2. Extraction
3. Filtration
4. Concentration
5. Drying
8. 1. Size Reduction
Objective:
•To ruptureplant organ, tissue& cell structuresso that its
medicinal ingredientsareexposed to theextraction solvent.
•Sizereduction maximizesthesurfacearea, which in turn
enhancesthemasstransfer of activeprinciplefrom plant
material to thesolvent.
The30-40 mesh sizeisoptimal.
Hammer mill or adisc pulverizer which hasbuilt in sieves
controlled by varying thespeed of therotor clearance
b/w thehammers& thelining of thegrinder.
9. parameters influencing
the quality of an extract
• Plant part used asstarting material
• Solvent used for extraction
• Extraction procedure
10. Selection of plant
• Plant based natural constituentscan bederived
from any part of theplant likebark, leaves,
flowers, roots, fruits, seeds, etc.
• Plantsareusually air dried to aconstant weight
beforeextraction.
• oven drying: every part werecut into pieces
dried in an oven @ 60°C for 9 hrs. &
pulverized.
• Other method for drying theplantsistheoven
drying at about 40°C for 72 h.
11. Filtration
• Theextract so obtained isseparated out from the
marc (exhausted plant material) by allowing it to
trickleinto aholding tank through thebuilt-in
falsebottom of theextractor, which iscovered
with afilter cloth.
• Themarc isretained at thefalsebottom, and the
extract isreceived in theholding tank.
• From theholding tank, theextract ispumped into
asparkler filter to removefineor colloidal
particlesfrom theextract.
12.
13. Concentration
• Theenriched extract from percolatorsor extractors, known as
miscella, isfed into awiped film evaporator whereit is
concentrated under vacuum to produceathick concentrated
extract.
• Theconcentrated extract isfurther fed into avacuum chamber
dryer to produceasolid massfreefrom solvent.
• Thesolvent recovered from thewiped film evaporator and
vacuum chamber dryer isrecycled back to thepercolator or
extractor for thenext batch of plant material.
• Thesolid massthusobtained is
pulverized and used directly for the
desired pharmaceutical formulations
or further processed for isolation
of itsphytoconstituents.
14. Drying
• Thefiltered extract issubjected to spray drying
with ahigh pressurepump at acontrolled feed rate
and temperature to get dry powder.
• Thedesired particlesizeof theproduct isobtained
by controlling theinsidetemperatureof the
chamber and by varying thepressureof thepump.
• Thedry powder ismixed with suitablediluentsor
excipientsand blended in adoubleconemixer to
obtain ahomogeneouspowder that can bestraight
away used (for example, for filling in capsulesor
making tablets).
15.
16. Variation in extraction
methods
• Length of theextraction period,
• Solvent used,
• pH of thesolvent,
• Temperature,
• Particlesizeof theplant tissues,
• Thesolvent-to-sampleratio.
17. The general techniques of
medicinal plant extraction
maceration,
infusion,
percolation,
digestion,
decoction,
hot continuousextraction (Soxhlet),
aqueous-alcoholic extraction by fermentation,
counter-current extraction,
microwave-assisted extraction,
ultrasound extraction (sonication),
supercritical fluid extraction,
phytonic extraction (with hydrofluorocarbon
solvents).
18. Extraction techniques
For aromatic plants
Hydrodistillation techniques(water distillation,
steam distillation, water and steam distillation),
Hydrolytic maceration followed by distillation,
expression and enfleurage(cold fat extraction)
Headspacetrapping,
Solid phasemicro-extraction,
Protoplast extraction,
Microdistillation,
Thermomicrodistillation,
Molecular distillation.
19. Maceration
• Thewhole/ coarsely powdered crudedrug isplaced in a
stoppered container with thesolvent.
• Allow to stand @ room temperaturefor aperiod of at least 3
days(& NMT 7 days) with frequent agitation until thesoluble
matter getsdissolved.
• Themixturethen isstrained, themarc (thedamp solid material)
ispressed,
• Thecombined liquidsareclarified by filtration or decantation
after standing.
• Thismethod isbest suitablefor usein caseof the thermo labile
drugs.
• Thisprocessismodified to multiple
• stageextraction to increaseyield
• of theactiveingredient.
20. Infusion
• Fresh infusionsareprepared by macerating
thecrudedrug for ashort period of timewith
cold or boiling water.
• Thesearedilutesolutionsof thereadily
solubleconstituentsof crudedrugs.
21. Digestion
• Thisisaform of maceration in which gentle
heat isused during theprocessof extraction.
• It isused when moderately elevated
temperatureisnot objectionable.
• Thesolvent efficiency of themenstruum is
thereby increased.
Image=microwave
Digestion system
22. Decoction
• In thisprocess, thecrudedrug isboiled in a
specified volumeof water (1;4) for adefined time,
• Volumeisreduced to 1/4th
theoriginal,
• It isthen cooled and strained / filtered.
• Thisprocedureissuitablefor extracting water-
soluble, heat-stableconstituents.
• Typically used in preparation of Ayurvedic extracts
= “quath” / “kawath”
23. Percolation
• It iscontinuousflow of solvent through thebed of crudedrug to
get extract.
• Used most frequently to extract activeingredientsin the
preparation of tincturesand fluid extracts.
• Thesolid ingredientsaremoistened with an appropriateamount
of thespecified menstruum,
• Allowed to stand for approximately 4 hours(minimum15 min) in
awell closed container, After stand time, themassispacked &
thetop of thepercolator isclosed.
• themixtureisallowed to maceratein theclosed V shaped
percolator for 24 h.
• It yieldsgreater conc. then maceration process.
24.
25. ,
• Additional menstruum isadded asrequired, until the
percolatemeasuresabout three-quartersof therequired
volumeof thefinished product.
• Themarc isthen pressed and theexpressed liquid is
added to thepercolate.
• Sufficient menstruum isadded to producetherequired
volume.
• Themixed liquid is
clarified by filtration or
by standing followed
by decanting.
26. Hot Continuous Extraction
(Soxhlet)
• Thefinely ground crudedrug isplaced in a
porousbag or “thimble” madeof strong filter
paper, which isplaced in chamber of the
Soxhlet apparatus.
• Theextracting solvent in flask isheated, and its
vaporscondensein condenser.
• Thecondensed extractant dripsinto thethimble
containing thecrudedrug & extractsit by
contact.
27. Soxhlet apparatus
• When thelevel of liquid in chamber risesto the
top of siphon tube, theliquid contentsof chamber
siphon into flask
• Thisprocessiscontinuousand iscarried out until
adrop of solvent from thesiphon tubedoesnot
leaveresiduewhen evaporated.
28. Aqueous Alcoholic Extraction
by Fermentation
• Somemedicinal preparationsof Ayurveda(asava &
arista) adopt thetechniqueof fermentation for
extracting theactiveprinciples.
• Theextraction procedureinvolvessoaking thecrude
drug, [powder / adecoction (kasaya)], for aspecified
period of time
• Undergoesfermentation & generatesalcohol in situ.
• Thisfacilitatestheextraction of theactive
constituentscontained in theplant material.
• Thealcohol thusgenerated also servesasa
preservative.
29. ,
• Someexamplesof Ayurvedic preparations:
karpurasava,
kanakasava,
dasmularista.
• If thefermentation isto becarried out in an earthen
vessel, it should not benew: water should first be
boiled in thevessel.
• In large-scalemanufacture, wooden vats, porcelain
jarsor metal vesselsareused in placeof earthen
vessels.
30.
31. Counter-current Extraction
• Wet raw material ispulverized using toothed disc disintegratorsto
produceafineslurry.
• Material to beextracted ismoved in onedirection generally in the
form of afineslurry within a cylindrical extractor whereit comesin
contact with extraction solvent.
• Thefurther thestarting material moves, themoreconcentrated the
extract becomes.
• Completeextraction isthuspossiblewhen thequantitiesof solvent
& material. Their flow ratesshould beoptimized.
• sufficiently concentrated extract comesout at oneend of the
extractor whilethemarc, practically freeof visible
solvent fallsout from theother end.
32.
33. Ultrasound Extraction
(Sonication)
• Theprocedureinvolvestheuseof ultrasound with
frequenciesranging from 20 kHz to 2000 kHz.
• Thisincreasesthepermeability of
cell walls& producescavitation.
Eg: extraction of rauwolfiaroot.
• Deleteriouseffect: Ultrasound energy (>20 kHz) on
theactiveconstituentsof medicinal plantsthrough
formation of freeradicalsand consequently
undesirablechangesin thedrug molecules.
34. The critical point represents the highest temperature and pressure at
which the substance can exist as a vapour and liquid in equilibrium.
The phenomenon can be easily explained with reference to the
phase diagram for pure carbon dioxide
Supercritical Fluid Extraction
35. Supercritical Fluid Extraction
• Cylindrical extraction vessels areused.
• Certain gasesbehavelikefreeflowing liquidsat critical point of
temp. & pressure, which havehigh penetration power &
extraction efficiency.
• Thisisfirst used in food packing industry for deodorization of
packed food. It issterileand bacteriostatic, nonexplosive,
harmlessto env. No wasteproduct found.
• In thisCO2 astheextracting fluid.(73.83 bar & 31.06°C)
• Thecomponent recovery ratesgenerally increasewith increasing
pressure/temperature.
• Thehighest recovery ratesin caseof argon,@ 500 atm & 150° C.
36. Advantage & disadvantage of SFE
• Advantage:
1. Higher diffusion rate, Lower viscosities, Higher vapour
pressure than liquid solvents.
2. Higher densities compared to gases, higher solvating power.
3. Solubility & selectivity can be modified.
4. Low polarity of CO2 can modified cosolvents.
5. Suitablefor heat sensitivecompound.
Disadvantage:
1. Low polarity, so cant extract polar compound
2. Presence of water may cause problems
3. Equipment are so expensive.
37.
38. SEPARATION AND ISOLATION OF CONSTITUENTS
The instrumentation for the structure for the structure
elucidation of organic compounds becomes effective and
allows the use of increasingly.
The most difficult operation in phytopharmacetical research
is the isolation and purification of plant constituents.
The physical methods used are chromatographic techniques
and methods such as fractional crystallisation, fractional
distillation, fractional liberation.
Chemical method is based on groups or moieties present in
the compound and chemical reactions.
39. FRACTIONAL CRYSTALLISATION
It is an important method for the purification of
compounds from mixture.
It depends upon the compound which form crystals at
the point of super saturation in the solvent in which it is
soluble
Many natural products are crystaline nature even in
mixture, process such as concentration, slow
evaporation, refrigeration are using for crystalisation
40. FRACTIONAL DISTILLATION
This method is used for the separation of
the components from volatile mixtures
Largely using in the separation of
hydrocarbons from oxygenated volatile
oil eg citral, eucalyptol
FRACTIONAL LIBERATION
In this process the groups of compounds
having the tendency of precipitation from
the solution.
Incertain cases the compounds may
modified by converting to its salt form.
This proces is often used in separation of
cinchona alkaloids, morphine etc.
41. SUBLIMATION
Here the compound is
heated the solid state
changes to gaseous state
without passing via liquid
state. Such compounds get
deposited in form of
crystals or cake.
This method is traditionally
used for the separation of
camphor from chips of
cinnamomum camphora.
42. CHROMATOGRAPY
Chromatography is widely used for the separation &
identification of components of a mixture.
Separation of chemical compounds is carried out by
mobile phase and stationary phase.
Chromatography can be classified according to mechanism of
separation as:
adsorption chromatography,
partition chromatography,
ion exchange chromatography,
size exclusion chromatography and affinity chromatography.
43. PAPER CHROMATOGRAPHY
The principle is partition
Mainly the stationary phase is
moisture present in the cellulose
fibers and mobile vary as we using.
The components separated based
on their solubility
The ratio between the distance travelled on the paper by a
component of the test solution & the distance travelled by the
solvent is termed the RF value. Under standard conditions, this
is a constant for the particular compound.
In practise, however, variations of the RF value often occur & it
is best to run a reference compound alongside the unknown
mixtures.
44. ADVANTAGES
i. Simple & inexpensive
ii. Sensitive – gives good separation of very
small amounts, of especially water-soluble
compounds, e.g. sugars.
DISADVANTAGES
i. Fragile – chromatogram may be destroyed
by chemicals used for visualization
ii. May be time-consuming.
45. THIN LAYER CHROMATOGRAPHY (TLC)
TLC is an e.g. of adsorption chromatography, the stationary
phase being a thin layer adsorbent held on a suitable backing.
Separation of the compounds present in the plant extract
depends on the differences in their adsorptive/desorptive
behaviour in respect of the stationary phase.
TLC involves a thin layer of adsorbent, mixed with a binder
such as silica gel, which is spread on a glass plate & allowed
to dry.
The plant mixture to be separated is applied as a spot near the
base of the plate, which is then placed in a closed glass tank
containing a layer of developing solvent.
46. ADVANTAGES OF TLC OVER PAPER CHROMATOGRAPHY
Separation of compounds
can be achieved more
rapidly & with less plant
material.
-The separated spots are
more compact & clearly
demarcated from one
another
-Reagents such as
concentrated H2SO4 would
destroy a paper
chromatogram, but ma be
used to locate the separated
substances on a TLC plate.
47. COLUMN CHROMATOGRAPHY
It is a method used to purify
individual chemical
compounds from mixtures of
compounds the principle of
separation is adsorption.
The classical preparative
chromatography column, is a
glass tube with a diameter from
5 mm to 50 mm and a height of
5 cm to 1 m with a tap and some
kind of a filter (a glass frit or
glass wool plug – to prevent the
loss of the stationary phase) at
the bottom.
48. GAS CHROMATOGRAPHY (GC)
It is an analytical technique for separating compounds based primarily on
their volatilities. (nitrogen, helium or argon)
GC provides both qualitative and quantitative information for individual
compounds present in a sample.
Compounds move through a GC column as gases, either because the
compounds are normally gases or they can be heated and vaporized into a
gaseous state.
The differential partitioning into the stationary phase allows the compounds
to be separated in time and space.
49. High-performance liquid chromatography (HPLC)
High performance liquid chromatography is a powerful tool in
analysis. This page looks at how it is carried out and shows
how it uses the same principles as in thin layer chromatography
and column chromatography.
50. Application of HPLC
1- Isolation and purification of biologically active natural products
2- Control of synthetic reactions
Identification of intermediates and target compound.
3- Biosynthesis study
Detection of biogenetic intermediates and enzymes involved.
4-Control the microbiological process
Used for separation of antibiotic from broth mixture
5- Pharmacokinetics study
Pharmacokinetic study comprises the measurement of drug metabolites
concentration in body fluids, absorption, bioavailability and elimination of
drugs
HPLC determines the drug and its metabolites in one step.
6- Stability test
Rapid method of analysis in stability test.
7- Quality control
HPLC is used to know the identity, purity and content of the ingredients
(drugs, raw and pharmaceutical products,
8- Drugs metabolisms
51. 9- Purification
refers to the process of separation or extraction the target
compound from other compounds or contaminants
10- Quantification of compounds by HPLC
Quantitative (assay) and qualitative determination of natural
products
11- Is the process of determination of the unknown
concentration of a compound in a known solution.
12- Identification of compound by HPLC through :
- Comparison of retention time with authentic
- Comparison of UV spectrum of the compound with that of
the authentic.
- Comparison of the Mass spectrum with that of the authentic.
52. Qualitative Reactions For The Detection Of Plant Constituents
Test for alkaloids
1. Dragendorff’s test
1 ml of extract, add 1 ml of Dragendroff’s reagent (potassium bismuth iodide
solution). An orange-red precipitate indicates the presence of alkaloids.
2.Mayer’s test
1 ml of extract, add 1 ml of Mayer’s reagent (potassium mercuric iodide
solution). Whitish or cream colored precipitate indicates the presence of
alkaloids.
3.Hager’s test
1 ml of extract, add 3 ml of Hager’s reagent (saturated aqueous solution of
picric acid). Yellow colored precipitate indicates the presence of alkaloids
4. Wagner’s test
1 ml of extract, add 2 ml of Wagner’s reagent (iodine in potassium iodide).
Reddish brown colored precipitate indicates the presence of alkaloids
53. Test for glycosides
Bontrager's test
In this test boil test sample with 1ml of sluphuric acid in a test
tube for 5min,filter while hot. Cool the filterate and shake with
equal volume of dichloromethane or chloroform then seperate
the lower layer of chloroform and shake it with half volume of
dilute ammonia. A rose pink to red colour is produced in the
ammonical layer.
Modified Borntragor’s Test:
To 1 gm of drug add 5 ml dilute HCl followed by 5 ml
ferricChloride (5% w/v). Boil for 10 minutes on water bath,
cool and filter, filtrate was extracted withcarbon tetrachloride or
benzene and add equal volume of ammonia solution, formation
of pink tored colour due to presence of anthraquinone moiety.
This is used C-type of anthraquinoneglycosides
54. Chemical tests for steroid and triterpenoid glycosides
Libermann Bruchard test:
Alcoholic extract of drug was evaporated to dryness and
extracted with CHCl 3 , add few drops of acetic anhydride
followed by conc. H2SO4 from sidewall of test tube to the
CHCl3extract. Formation of violet to blue coloured ring at
the junction of two liquid, indicate the presence of steroid
moiety.
Salkovaski test:
Alcoholic extract of drug was evaporated to dryness and
extracted withCHCl3, add conc. H2SO4 from sidewall of test
tube to the CHCl3 extract. Formation of yellow colored ring at
the junction of two liquid, which turns red after 2 minutes,
indicate the presence of steroid moiety
55. Chemical tests for cardiac glycosides
Keller Killiani test:
To the extract of drug equal volume of water and 0.5 ml of strong lead acetate
solution was added, shaked and filtered. Filtrate was extracted with equal
volume of chloroform. Chloroform extract was evaporated to dryness and
residue was dissolved in 3 ml of glacial acetic acid followed by addition of
few drops of FeCl3 solution. The resultant solution was transferred to a testube
containing 2 ml of conc. H2SO4. Reddish brown layer is formed, which turns
bluish green after standing due to presence of digitoxose.
Legal test:
Treat the test solution with 2ml of pyridine and sodium nitropruside 2 ml was
added followed by addition of NaOH solution to make alkaline. Formation of
pink colour in presence of glycosides or aglycon moiety.
Baljet test:
Treat the test solution with picric acid or sodium picrate solution, it forms
yellow to orange colour in presence of aglycones or glycosides
56. Goldbeater’s skin test: Goldbeater’s skin is a membrane produced from the
intestine of Ox. It behaves just like untanned animal hide. A piece of
goldbeaters skin previously soaked in 2% hydrochloric acid and washed with
distilled water is placed in a solution of tannin for 5 minutes. It is then
washed with distilled water and transferred to 1 % ferrous sulphate solution.
A change of the color of the goldbeater’s skin to brown or black indicates the
presence of tannin. Hydrolysable and condensed tannins both give the
positive goldbeater’s test while pseudo tannins show very little color or
negative test.
Tests for tannins
Phenazone Test: To 5 ml of aqueous solution of tannin containing drug,
add 0.5 g of sodium acid phosphate. Warm the solution, cool and filter.
Add 2 % phenazone solution to the filtrate. All tannins are precipitated as
bulky, colored precipitate.
Gelatin Test: To a 1 % gelatin solution, add little 10 % sodium chloride. If
a 1 % solution of tannin is added to the gelatin solution, tannins cause
precipitation of gelatin from solution.
57. Tests for flavonoids:
Shinoda Test: To the test solution, and few drops of conc.
HCl. To this solution 0.5 g of magnesium turnings were
added. Observance of pink coloration indicated the presence
of flavonoids.
With Lead Acetate: To the small quantity of test solution lead
acetate solution was added. Formation of yellow precipitate
showed the presence of flavonoid.
With Sodium Hydroxide: On addition of an increasing
amount of sodium
hydroxide, the ethanolic extract showed yellow coloration,
this decolorized after addition of acid.
58. Tests of protein
Biuret test
On adding 1% copper sulphite to alkaline solution (4% NaOH solution) of
protein, a violet colour is developed. This test is due to the presence of peptide
linkage.
Xanthoproteic Test:
To 5ml test solution add 1ml of Con.HNO3 and boil, yellow ppt is formed.
On addition of NH4OH, yellow ppt. turned orange.
Nihydrin test
When protein is boiled with a dilute solution of ninhydrin, a violet colour is
produced.
63. The traditional methods
for essential oil extraction
• Water distillation,
• Water and steam distillation,
• Steam distillation,
• Cohobation,
• Maceration,
• Enfleurage.
64.
65. methods
1. Distillation: Originally introduced by Von Rechenberg.
•water distillation.
•water and steam distillation.
•direct steam distillation.
2. Hydrolytic maceration distillation.
3. Expression.
4. Cold fat extraction / Enfleurage.
66. • Distillation methodsaregood for powdered
almonds, rosepetalsand roseblossoms.
• Maceration isadaptablewhen oil yield from
distillation ispoor.
• Solvent extraction issuitablefor expensive,
delicate& thermally unstablematerialslike
jasmine, tuberose, and hyacinth.
• Water distillation isthemost favored method of
production of citronellaoil from plant material.
68. Concrete
• Thisisan extract of fresh flowers, herbs, leavesand the
flowering topsof plantsobtained by theuseof ahydrocarbon
solvent such asbutane, pentane, hexaneand petroleum ether.
• Concreteisrich in hydrocarbon solublematerial & devoid of
water-solublecomponents.
• It isgenerally awaxy, semisolid, dark-colored material free
from theoriginal solvent.
• concretesareproduced in
static extractors.
• It isanormal practiceto circulatefresh
solvent through abattery of extractors.
• The enriched solvent from the extractor is pumped into an
evaporator for solvent recovery & the solvent content is reduced
to about 1/10th
the original volume.
69. Absolutes
• To makean absolute, theconcreteismixed with absolutealcohol
& agitated thoroughly in avessel with an agitator.
• During agitation, thetemperatureiskept at 40°-60° C and the
concreteisimmersed in thesolution.
• Thesolution iscooled down to -5° to -10° C to precipitateout the
wax, sincewaxesarenormally insolublein alcohol below -1° C.
• Theprecipitated wax isremoved by passing thesolution through a
rotary filter.
• Thefiltratefrom therotary filter ispumped into aprimary
evaporator, whereit isconcentrated to about 10% alcohol content.
• Finally, theconcentrated extract ispumped into an
agitating-typeevaporator, wherethealcohol
iscarefully removed under high vacuum.
70. Resinoids
• Resinoid isan extract of naturally resinousmaterial,
madewith ahydrocarbon solvent.
• Resinoidsareusually obtained from dry materials.
• Theextraction processissameasthat of concrete
production, except that perforated discsarenot used
for stacking thematerial;
• instead powder from dry plant
material isfed into theextractor.
71. Pomades
• Pomadesareobtained by aprocessknown as
enfleurage, which isacold fat extraction method.
• Thefat isspread out on glassplatescontained in wooden
frames, leaving aclear margin near theedges.
• Theabsorptivesurfaceof thefat isincreased by surface
groovesmadewith awooden spatula.
• Fresh flowersarespread out on thesurfaceof thefat and the
framesarestacked in piles.
• After theperfumeoilshavebeen absorbed from theflowers,
thespent flowersareremoved by hand.
• Fresh flowersareagain spread on thefat surface.
• Thisisrepeated until thefat surfaceiscompletely enriched
with perfumeoils.
• Thepomadeso obtained isready for cold alcoholic extraction
72.
73. major constraints in sustainable industrial
exploitation
• Poor agricultural practicesfor MAPs,
• Unscientific and indiscriminategathering practicesfrom thewild, poor
postharvest & post-gathering practicesleading to poor quality raw
material,
• Lack of research for thedevelopment of high-yielding varietiesof
medicinal and aromatic plants-MAP’s.
• Poor propagation methods.
• Inefficient processing techniques.
• Poor quality control procedures.
• Lack of research on process
& product development.
• Difficulty in marketing.
• Non-availability of trained personnel.
• Lack of facilities& toolsto fabricateequipment locally.
• Finally lack of accessto thelatest technologies& market information.
74. Conclusion
• Theprocessof extracting MAP’sdetermineshow
efficiently weadd valueto MAPbio-resources.
• In thecaseof essential oils, theextraction process
affectsthephysical aswell asinternal composition.
• Variationsin thechemical constituentsof theextractsof
medicinal plantsmay result by using non-standardized
proceduresof extraction.
• Effortsshould bemadeto produce
batcheswith quality asconsistent
aspossible.
77. • PROPERTIES:
• Atropine is optically inactive levorotatory isomer of
Hyoscyamine.
• It consist of colorless needle like crystals or white crystalline,
colorless, odorless powder.
• It is a strong poison with a sharp bitter taste.
• It is Sublimes in high vaccum at 93°C to 110°C.
• Sparingly soluble in water but freely dissolve in alcohol,
benzene & dil. acids.
• USE:
• Due to its dilating action on pupils of the eye it is used in
Ophthalmology.
• Atropine: water (1:1,30,000) ratio use to cause dilation of the
pupils of cat’s eye.
• When taken internally, 1st
stimulate & than depresses the CNS.
78. • ISOLATION:
• It is isolated from juice or powdered drug of Hyoscymus muticus
(Egyptian)
Powder drug
Moistened with ↓ aq. Sol. Of Na2CO3
extracted with ↓ ether or benzene
Free bases are found
extracted with ↓ water & acidified with acetic acid
shaken with ↓ ether to remove coloring matter
Alkaloids are precipitated with Na2CO3, filtered off, washed & dried.
Dissolve in ether or acetone & ↓ dehydrated with anhydrous sulphate
filtration ↓ Concentration & cooling
Crude crystals of hyoscymine & atropine
dissolved in ↓ alcohol & mixed with NaOH
Allow to stand till hyoscymine is completely racemised to atropine
crude atropine purified by crystallization from acetone.
79. • Identification:
• Vitali-Morin Test:
• Dilute solution of atropine treated with conc. HNO3 this
mixture evaporated to dryness on steam bath produce pale
yellow residue.
• This residue gives violate color when a drop of freshly
prepared KOH is added.
• TLC of Atropine:
• 1 % sol. Of atropine prepared in 2N acetic Acid is spotted
on plate & eluted in solvent system of strong ammonia
solution: methanol (1.5:100).
• Than plate spraying with iodoplatinate solution shows Rf
value 0.18.
• Atropine sulphate showes Rf value 0.70, in the solvent
system acetone: 0.5 M NaCl spraying with dragendorff’s
reagent.
