1. GPAT Discussion Center
PHARMACOGNOSY
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Guidelines and tips
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community
Ask the community for help and clear up your study doubts
University Rankings
Discover the best universities in your country according to Docsity users
Free resources
Our save-the-student-ebooks!
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
Pharmacognosy notes full chapter is covered, Study notes of Pharmacognosy
Full notes.......... All notes can easily find out
Typology: Study notes
2018/2019
1 / 9
This page cannot be seen from the preview
Don't miss anything!
Related documents
Partial preview of the text
Download Pharmacognosy notes full chapter is covered and more Study notes Pharmacognosy in PDF only on Docsity!
PHARMACOGNOSY
MICROSCOPY AND OTHER SOME IMPORTANT POINTS OF DRUGS
Volatile oil containing drugs
A. Eucalyptus oil:
- Trichomes are absent 2. Presence of Sunken stomata 3. Epidermis is polygonal 4. Presence of schizogenous oil glands, both prismatic and spharides calcium oxalate
B. Cardamom (Elettaria cardamom):
- Seeds are derived anatropous ovules. They are irregularly triangular shaped coverd with transverse wrinkles known as rugae. Korarima cardamom does not show presence of rugae. Transverse section of seed shows the presence of arillus.
- Epidermis of Pericarp made up of polygonal tubular cells.
- Mesocarp contains partially lignified fibrovascular bundles.
- Different variety of cardamom is distinguished by morphologically and sclerenchymatous cells present per square mm.
- Cardamom can be distinguished from crude drug by its ash value.
C. Cassia cinnamon / Chinese cinnamon: Chinese cinnamon
1. Stem bark is Single quill
- Complete stem bark and cork contains polygonal tubular cells
- Pericycle is made up of continuous band of stone cells and lignified pericyclic fibers are embedded in sheath of stone cells
- Acicular calcium oxalate crystals and starch grains are abundant
- It contains coumarin
- Cinnamic aldehyde is main chemical constituent while very small amount of eugenol
Indian cinnamon
1. Compound quill
- It is inner bark so it lacks cork and primary cortex. 3.Perocycle is prominent with sclerenchymatous cells
- Acicular calcium oxalate and starch grains
- It does not contain coumarin
- 5- 10 % eugenol
- Cassia oil only contains cinnamic aldehyde. So it only give brown colour
- Ferric chloride + cinnamic aldehyde Brown colour
- Orthospermic fruit
- Anomocytic stomata
- Trichomes and starch grains are absent.
- Rosette crystals of calcium oxalate
- Parquetry arrangement of cells on the inner epidermis of Pericarp.
H. Anise (Pimpinella anisum): a. Epidermis is fruit covered with unicellular conical thick walled warty trichomes, b. Rosette calcium oxalate crystals
I. Crocus / Kesar / Saffron (Dried style and stigma of crocus sativum)
Crocin + crocetin Red coloring principals
Picrocrocin Bitter principal
Protocrocin 2 Picrocrocin + 1 crocin
Crocetin
Glucose + Safranal
Crocin + H2SO4 Blue color
J. TAXUS (Taxus Brevifolia): give Taxol which is a diterpenoid that stimulate α and β tubulin which polymerise to give microtubules and for these process microtubules associated protein (MAP) and GTP is necessary. Taxol brings the polymerization in the absence of MAP and GTP. Due to enhanced microtubules can detrimental effects on dividing cells which leads to blockage of cell cycle. 10-deacetyl baccatin III is converted to Taxol by tissue culture.
K. FORSKOLIN: is a diterpenoid used as vasodilator and cardiac stimulant (positive ionotropic). It acts as vasodilator via activation of activation of adenyl cyclase. It is also used to lower the intraocular pressure.
ALKALOIDS
True alkaloids: contain heterocyclic Nitrogen which is derived from amino acid and always basic in nature due to presence of lone pair of electrons on nitrogen.
Proto alkaloids: are simple amines in which Nitrogen is not heterocyclic. E.g. ephedrine, Colchicine, mescaline
Pseudo alkaloids : they are not derived from amino acids but they show positive test for alkaloids. E.g. purines (caffeine), steroidal and terpenoidal alkaloids Conessine, solanidine, protoveratrine, aconine.
Volatile alkaloids: coniine, nicotine, sparteine
Colored alkaloids: Berberine (yellow), Betanidin (Red)
- Some of proto and pseudo alkaloids show higher solubility in water e.g. Colchicine, caffeine, quinine HCl are freely soluble in water. So solubility of alkaloid is also employed for extraction procedures.
Alkaloids with Primary amine Nitrogen: Mescaline
Alkaloids with Secondary amine Nitrogen: Ephedrine
Alkaloids with Tertiary amine Nitrogen: Atropine
Alkaloids with Quaternary Nitrogen: Tubocurarine
Chemical test:
i. Mayer’s reagent test (K +^ mercuric iodide solution) Cream colored ppt ii. Dragendroff’s reagent (K +^ bismuth iodide solution) Red brown ppt iii. Wagner’s reagent (iodine K+^ iodide solution ) Red brown ppt iv. Hager’s reagent (Picric acid) Yellow colored ppt v. Picrolonic acid Yellow colored ppt
Classification:
a. Pyrrole and Pyrrolidine ring: Hygrine, Cocoa b. Pyridine and piperidine : Coniine, Arecoline, Lobeline c. Quinoline : Camptothecin (Anticancer) , Quinine, Cinchonine d. Isoquinoline: D-Tubocuarine (Skeletal muscle relaxant), Morphine, Berberine, Emetine e. Indole: Ergot, Reserpine, Vinca, Strychnine, Physostigmine f. Imidazole: Pilocarpine g. Quinazoline: Vasaka (antitussive & expectorant) h. Tropane: Datura
R. Densiflora contains Sclerenchyma which is absent in R. serpentina
R. Tetraphylla has uniform cork.
Reserpine + conc. Nitric acid Red color
Reserpine + vanillin in acetic acid Violet red color
D. Vinca (Catharanthus roseus ) a. Presence of Anisocytic stomata b. Calcium oxalate crystals are absent.
Vinblastine contains a indole alkaloid part called as cathranthine and dihydroindole alkaloid is called as vindoline.
Vinblastine is anti neoplastic drug and act by causing the mitosis arrest or by interfering with amino acid metabolism. It is mostly used in treatment of Hodgkin’s disease and lymphomas.
E. Opium: Dried latex obtained by incision from unripe capsules of Papaver somniferum. Largest production is in Afghanistan. In India its cultivation is restricted to M.P, U.P and Rajasthan. Narcotine / Noscapine was the first alkaloid reported in opium. Capsules incised vertically with ‘Nushtar’ which is needle like apparatus penetrates up to 2 mm in afternoon. Opium factor in India is at Ghazipur. The best climate conditions for opium is soil pH 7, rich in organic matter, cool whether without freezing temp.
Indian opium Cubical species Parisian opium Brick shaped Turkish opium Conical or rounded
Benzyl Isoquinoline derivatives: Noscapine, Papaverine , Narceine Phenanthrene derivatives: Morphine, Codeine, Thebaine
- Morphine, codeine, Narcotine are levorotatry while Paperverine is optically inactive.
- The opium alkaloids are present a strong monoacidic base as a salt of meconic acid.
Chemical test:
1. Opium extract + FeCl 3 Reddish purple color **(Due to presence of meconic acid )
- Morphine + HNO 3 Orange red color while codeine donot respond
- Morphine + K 3 Fe (CN 6 ) Bluish green while codeine do not respond
- Papaverine + HCl + K 3 Fe (CN 6 ) lemon yellow color**
Papaverine is used as smooth muscle relaxant
Narcotine / Noscapine and codeine are used as antitussive
Thebaine is convulsant
Morphine on removal of water molecule gives apomorphine which is a strong emetic and used to treat poisoning by giving subcutaneous route.
- The other varieties of opium / poppy that does not contain morphine are P.bracteatum, P. argemone. These are rich in Thebaine.
F. Curare: (South American arrow root poision) obtained from chondrodebdron tomentosum and main chemical constituent is benzylisoquinoline derivative (+) Tubocurarine used as neuromuscular blocker or skeletal muscle relaxant and in myasthenia gravis.
G. Ipecac (Cephaelis acuminita):
i. Characteristic feature is presence of opalescent parenchymatous cells ii. Presence of acicular raphides and polyhedral parenchyma. iii. Presence of mullar shaped starch grains iv. Brazilian ipecac has annulated roots and pith is absent while Indian ipecac or panama does not have annulated roots but have transverse ridges.
Emetine in smaller doses used as expectorant while in higher dose as emetic. Emetine is also used as antiprotozoal i.e. Entamoeba histolytica is sensitive in very low conc. 1 in 6 millions. Cephaeline has more emetic and less expectorant action as compared to emetine.
Chemical tests:
Powdered drug + HCl +H 2 O. Shake well and filter. To filtrate + KCLO4. Yellow color is obtained changing to Red due to presence of emetine. Emetine + H (^) 2SO 4 + Molybdic acid Green color
H. Tropane alkaloids (Pyrrolidine + Piperidine ring):
They are biosynthesized in root and then migrate to leaves. Atropine is racemic form of hyoscyamine. L- Hyoscine or scopolamine which has an epoxide ring is used in preanesthetic medication in surgery and motion sickness. Tropane alkaloids give + ve test to Vitali-Morin reaction.
a. Belladonna (Deadly night shade): Atropa belladonna is European belladonna