Pharmacognosy
Sherif S. Ebada, Ph.D.
Contact information:Assoc. Prof. Dr. Sherif S. EbadaPharmaceutical Chemistry Dept.Office hours:
Tuesdays and Thuresdays: 10:00 am–12:00 pmE-mail: [email protected]
Lecture 9AB
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Introduction to Unorganized Drugs
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Definition of Unorganized Drugs• They are either mixtures of chemical substances or
decomposition products of substances originally present in thebiological source of the drug.
• They are derived from parts of plant or animals.
• Either normally or pathologically.
• Obtained by some process of extraction such as incision,decoction & expression.
• No cellular or definite structures.
• They are mostly solids, but some are liquids such as oils &balsams.
• Morphological terms are unapplicable so we use various physicalcharacters of form as color, solubility in common solvents;chemical tests.
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Classification of Unorganized Drugs1. Resin & Resin Combinations:
A. Resin: Colophony, Guaiacum, CannabisB. Oleoresin: MasticC. Oleogumresin: Myrrh, Galbanum, Olibanum.D. Gum resin: AmmoniacumE. Balsams: Benzoin, Peru, Tolu, Prepared storax
2. Gums: Acacia, Tracaganth, Karaya, Manna, Guar, Pectin3. Dried Extracts: Agar, Gelatin, Catechu.4. Dried Juice: Aloes.5. Dried Latex: Opium.6. Lipids.7. Proteins.8. Oils: Evening primrose, Theobroma, Olive, Castor.9. Waxes: Beeswax, Carnuba wax10. Saccharine Substances: Honey, Royal jelly, Bee propolis
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1- Resins & Resin Combinations
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1- Resins & Resin Combinations
General Characters:
1. Obtained by distillation, plant punctures &extraction.
2. Present in oleoresin cells, whole tissue, ducts &glands produced on injury or naturally
3. Hard, solid or semisolid, amorphous organicsubstances of complex nature.
4. Insoluble in water, partially soluble in petroleumether, soluble in alcohol, chloroform, ether and inmany organic solvents as well as fixed & volatileoils.
5. Upon heating, soften & melt with a smoky flame
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How can we obtain resin alone?1. Distillation of the volatile oil from the oleoresin e.g.
Colophony from Turpentine.
2. Heating the plant part e.g. Guaiacum from Guaiacumwood.
3. Plant punctures (naturally or artificially).
4. Extraction with ethanol then precipitating withwater e.g. Jalap.
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Resin constituents
1. Resin acids e.g. abietic, benzoic, cinnamic orcommiphoric acids.
2. Resin esters & their degradation products; resinalcohols (resinols) & resin phenols (resinotannol).
3. Resenes; inert hydrocarbon.
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1-Resin & resin combination
A- Resin
Colophony
Cannabis
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Colophony (Rosin)
• Syn.: Resina Terebinthinae,Rosin.
• Origin: It is the residue leftafter distilling the volatileoil from the oleoresinobtained from Pinus palustrisFamily Pinaceae
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Colophony (cont’d.)Occurrence & description:• It occurs as large compact, shiny, angular,
brittle, glassy pale amber masses frequentlyconverted into a yellowish white powder
• The colophony oleoresin is produced by thetrees in schizogenous ducts & is greatlyincreased by injury
• Soluble in alcohol, insoluble in water.
• Fracture: glassy.
• Odor: Faintly terebinthinate.
• Taste: bitter.
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Colophony (cont’d.)• Active constituent:
Abietic acid is the major constituent of colophony.
• Uses:
1. Used as diuretic.
2. Ingredient of ointments & plasters in chronic gout & rheumatism.
3. Paints dryer & floor paintings.
Chemical Test
Shake an amount of freshly powdered colophony in petroleum ether and filter. Shake the filtrate with an equal volume of Copper acetate, a emerald green colour is produced in the organic layer (Test for abietic acid).
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Cannabis القنب،الحشيش
• Collection and preparation:Hashish (or Charas) is the crude resinThe resin is secreted by numerous glandular hairs
found on the bracts and bracteoles that encloses the ovary of the flowering tops.
Obtained by rubbing the tops between the hands, beating them in clothes or carpets .
The resin is scraped off.The Indian cannabis contains 20% or more resin In temperate region, hemp produces 6 % or less.
•Origin:The resin obtained from the dried flowering topsof pistillate (female) plants of Cannabis sativa,family Cannabinaceae.
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Cannabis (cont’d.)• Active constituents:Cannabinoids: the main constituent is 9∆ tetrahydrocannabinol (9∆ THC).
Cannabinol, cannabidiolic acid and 8∆ THC
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• Chemical tests:
Modified Beam’s test:• Methanol extract ETD extract the residue with Pet. ether filter wash the
filterate with Na2CO3 followed by dil H2SO4 and H2O ETD residue + few drops of N/10 alc KOH A purple colour
• Uses:1. Indian Hemp: sedative and hypnotic
2. 9∆ THC : antiemetic, used orally in ttt of nausea and vomiting associated with cytotoxic drugs in cancer chemotherapy.
3. Cannabis oil is very effective in reducing pain, inflammation and as an anticancer.
1-Resin & resin combination
B- Oleogum resinMyrrh
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Myrrh Name
Gummiresina Myrrha;
Bola; Myrrh; Gum Myrrh
Syn.
Oleogum resin from the
stems & branches of
Commiphora molmol
Family Burseraceae
Origin
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Myrrh Name
V.O.; (cumminaldehyde &
eugenol).
Resin (β & γ commiphoric
acid).
Gum (acacia type containing
oxidase enzyme).
Expectorant.
Sore throats & gingivitis.
Hemmorrhoids, bed sores &
wounds.
Bilharziasis.
Analgesic.
A.C.
Uses
Myrrh المر
2-Gums •Gum Acacia.
•Gum Tragacanth
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Gums• Gum are amorphous, translucent or transparent solids;
insoluble in alcohol & in most organic solvents butsoluble in water yielding viscous, usually adhesivecolloidal solutions.
• Produced either by injury or by unfavorable growthconditions or changes in existing cell walls.
• Chemically, gums consist of Ca, Mg & K salts ofpolyuronoides that are hydrolyzed by boiling withdilute acids into monosaccharide sugars & uronicacid.
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Gum Acacia
• Syn.: Gum Arabic; Acacia.
• Origin: Dried gummyexudation from the stem &branches of Acacia senegal,family Leguminoseae
(Fabaceae).
Gum Tragacanth
• Syn.: Gum Tragacanth
• Origin: Dried gummy exudationobtained from the incision ofAstragalus gummifera, familyLeguminoseae (Fabaceae).
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Gum Acacia
• Occurrence: roundedovoid tears; whitish oryellowish white; opaquefrom numerous fissurespresent in the tears.
• Odor: odorless.
• Taste: mucilaginous.
Gum Tragacanth
• Occurrence: thin, curved,ribbon flakes, spirallytwisted linear pieces;white to pale yellowishwhite.
• Odor: odorless.
• Taste: mucilaginous.
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Active Constituents & UsesGum Acacia
• Arabin (complex mixture of Ca, Mg & K salts of arabic acid
• Oxidase enzyme******.
Gum Tragacanth
• Bassorin (60-70%), a complex of polymethoxylatedacids; swells in water
• Tragacanthin (30%); demethoxylated bassorin; water soluble.
• Starch******.
Uses:
1. Emulsifying agent.
2. Suspending agent.
3. Demulcent & emollient in cosmetics & hand lotion.
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Chemical TestsGum Acacia
1. Oxidase enzyme test:aq. soln. of gum, add few drops H2O2 & few drops tincture benzidine, shake then allow to stand, a deep blue color is formed
2. To an aq. Soln. of gum, add 1 ml of lead subacetate[Pb(Ch3COO)2], a flocculent white ppt is formed
3. To 1g of powder, add 1 ml of N/50 Iodine, a yellow brown color is produced
Gum Tragacanth
1. Oxidase enzyme test: Negative.
2. To an aq. Soln. of gum, add 1 ml of lead subacetate[Pb(Ch3COO)2/Pb(OH)2], a flocculent white ppt is formed.
3. To 1g of powder, add 1 ml of N/50 Iodine, a yellow color is produced with few blue spots.
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3- Dried Extracts
•Agar.
•Gelatin.
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Dried Extracts
• These are drugs prepared by theevaporation of the aqueous decoctionfrom parts of certain plants or animals.
• Examples include:A.Agar-Agar
B.Gelatin
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Agar-Agar
• Syn.: Japanese Isinglass.
• Origin: Dried mucilagenous substance prepared from bleached and dried species of red algae mainly Gelidium species (Gelidium corneum & Gelidiumcartilagineum), family Gelidiaeae and other closely related allied red algae of Japan.
• Occurrence & description: translucent, yellowish white masses.
• Odor: odorless.
• Taste: mucilaginous.
• Solubility: insoluble in cold water but soluble in hot water. 1% solution in hot water, forms stiff jelly upon cooling.
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Agar-Agar (cont’d.)
• Active constituents:– Ca salt of polysaccharide.
– The 2 principal constituents:• Agarose (the neutral galactose polymer freefrom sulphate ion), responsible for the gelstrength of agar.
• Agaropectin (the sulphonated polysaccharide),responsible for giving agar its viscosity.
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Agar-Agar (cont’d.) Tests for identity:
Positive test with Molish.
Boil with dil HCl and filter
On the filtrate carry out the following tests:
Fehling’s reduction test ------------ Positive
On powder carry out the following tests:
Boil 1g in 100 ml water, cool------------------- stiff gel.
Uses:
1. Used in the preparation of culture media.
2. An emulsifying & suspending agent.
3. Bulk laxative.
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Origin: The gel-forming proteins obtained by partial
hydrolysis of insoluble collagenous byproducts from meat industry as
skin, bones, and tendons of cattle, sheep by treating with hot water.
The solution is then purified & concentrated to a solid
form.
Physical Characters:
Shape: Sheets or strips or powder
Color: Colorless or pale yellow translucent.
Odor: Odorless.
Taste: Tasteless.
Gelatin
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Gelatin (cont’d.)
Solubility:
Insoluble in cold water but absorbs a considerable volume ofliquid (swells).
It dissolves on heating, yielding a jelly on cooling. Its gelatinizingpower is reduced by long heating.
• Active Constituents:
– protein glutin.
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Gelatin (cont’d.)• Uses: Pharmacy:
Used widely in the pharmaceutical industry: in hard, soft gelatin capsules, emulsions.
Combined with glycerin to form glycerinated gelatin, employed as a vehicle and in manufacture of suppositories.
Suspending, stabilizing and thickening agent.
Microencapsulation.
Bacteriological culture medium.
Clinically:
Plasma substitute, homeostatic dressing, protective drugs for stomach
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Gelatin (cont’d.)Chemical Tests:
Shows positive tests for protein but should not precipitate with diluteacids (characteristic of chondrin).
Test for identity:
When heated with soda lime----------Ammonia odor.
Solution + Picric acid -----------------Canary yellow ppt.
Solution + Tannic acid --------------- White ppt.
Biuret’s Test:
To a solution of gelatin, add drops of CuSO4 soln. & excess NaOH, a
violet color is produced
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4- Dried Juices
•Aloes
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Dried Juices
• Juices are fluidly plant saps containing
dissolved substances & usually present
in special structures within the plant.
• Example: Dried Juices of Aloe
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• Origin: Aloes is the solid residueobtained by the evaporation of theliquid which drains from transverselycut leaves of Aloe ferox (Cape Aloe) &Aloe vera or Aloe barbadensis(Curacao Aloe), family Liliaceae.
• Solubility: Aloes are partly soluble inwater but entirely soluble in alcohol.
Aloes
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Aloe (cont’d.)ALOE DRIED JUICE
Active Conistituents
Anthraquione glycosides:
Anthracene derivatives (Aloins):
• Called Aloins mainly pale yellow crystalline substance
“Barbaloin” which is anthrone C-glycoside.
• Aloinosides A, B (Barbaloin + Sugar in an O-linkage);
• Free aglycones (Aloe-emodin, Chrysophanol);
Resins called “Alosin” which has a strong purgative action.
A polysaccharide with potent immunostimulatory activity.
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Aloe (cont’d.)Aloe gel
The mucilagenous gel obtained from the cells making up the inner portion (parenchyma) of the leaf of Aloe species, family Liliaceae.
The Aloe gel is composed of:
It is a mucilage of polysaccharide nature of three main categories:
1- Neutral polysaccharides.
2- Partially acetylated polysaccharides.
3- Acidic polysaccharides.
Vitamins.
Minerals
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• Uses:
Aloe juice
• Powerful purgative should be administered with an antispasmodic medication
• Anti-microbial (Tr. Benzoin Co).
• Anti-inflammatory.
• Effective against Herpes simplex virus
Aloe gel
• Used in cosmetic purposes for its emollient moisturizing & healing properties.
• Antiviral, antibacterial and antifungal activity
• Cancer preventive agent.
Aloe (cont’d.)
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Aloe (cont’d.)Chemical tests:
Prepare an aqueous soln. by boiling in water followed by filteration:
1. Borax Test for Anthranols: Add 0.2 g of borax to 5 ml of the aloesoln. and boil. Pour few drops of this soln. to a test tube of water, a greenfluorescence is produced. This test is general for all varieties of Aloe.
2. Modified Borntrager’s test for C-glycosides: Powder + 10 ml FeCl3+ 5 ml dil. HCl, heat for 10 minutes, filter, cool, Shake with benzene andallow to separate. Shake the benzene layer with NH3 ------> a rose redcolour is produced in the lower aqueous layer.
3. Nitric acid test: To differentiate between differentAloe varieties.
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5- Dried Latex
Opium
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Dried Latex
• Latex is the milky sap of many plants thatcoagulates on exposure to air. It is an emulsion orsuspension in which the aqueous phase is composed ofmineral salts, proteins, sugars, tannins & alkaloids.The oily phase is composed of oils, resins, etc.
• Latex is usually produced in:– Laticiferous cells
– Laticiferous tubes.
– Laticiferous vessels (originate from many cells): e.g.Opium
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Opium• Syn.: Poppy Latex , Gum opium.
• Origin: Raw opium is the dried milkyexudation obtained by incising the unripe butfully grown capsules of Papaver somniferum,family Papveraceae.
• The quality of opium is judged by morphinecontent which is required to be n. l. t. 9.5%by the USP.
• Commercial varieties include Turkish,Persian, Indian & Yugoslavian opium
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Opium (cont’d.)
Active constituents:
• Opium contains more than 19 alkaloids,
• some of which are combined with meconic acid, others with
sulfuric acid and some as free alkaloids.
Action & Uses:
• Morphine:
1. Most powerful analgesic used in cases of severe pain as post-operative pain, bone fractures, cancer patients & in cases of angina.
2. Precede the use of anesthetics to increase their efficacy
3. Used as an antagonists for poisonous effects of other alkaloids as strychnine, atropine, phytostigmine.
4. Opium is preferable to morphine in persistent summer diarrhea or cholertic diarrhea.
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Opium (cont’d.)
Action & Uses (cont’d.)
• Codeine:
1. It is weaker in intensity than morphine.
2. It produces less tendencies to addiction.
3. Codeine depresses the cough center in the brain.
4. It causes constipation & hypnosis.
• Heroin:
1. It is the synthetic diacetyl derivative of morphine.
2. It is 5 X more potent as morphine.
• Papaverine:
1. it is a smooth muscle relaxant
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Opium (Cont’d.)
• Important Terminology:
– Opiate: Narcotic analgesic from natural source.
– Opioid: Narcotic analgesic that is synthetic or
semisynthetic.
– Opioid peptides: Polypeptides secreted in the brain in
cases of pain and have morphine like action e.g. endorphins.
– Non-narcotic analgesic: only reduces pain e.g. NSAIDs.
Naloxane is a potent morphine antagonist used to treat
morphine overdose and addiction.
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