ALKALOID general introduction pharmacognosy

Pharmacognosy -II B pharmacy students help for understanding to easy with concept.

1. ALKALOID Mr. Raj D. thorat M.Pharm Assistant Professor Rajarshi shahu college of pharmacy, markhel .

2. Contents Introduction History Alkaloids Are Found In Properties Classification Of Alkaloids Chemical Tests For Alkaloids Alkaloids containing drugs References

3. Introduction Alkaloids are a group of naturally occurring chemical compounds, that contain mostly basic nitrogen atoms . Alkaloids are basic nitrogen – containing compounds obtained from plants, animals, bacteria & fungi . Alkaloids are the natural products are also called secondary metabolites products. Alkaloids are the role of secondary metabolites in plant defense system. The term alkaloids was coined by Meissner in 1819. The term alkaloids derived from Alkali like generally nitrogen is in heterocyclic rings ( Primary, secondary, tertiary or quaternary amines).

4. History Isolation Of Alkaloids Years Opium & Narcotine 1803 Emetine & Strychnine 1817 Caffeine & Colchicine 1819 Quinine 1820 Papaverine 1821 Thebaine 1835

5. Alkaloids Are Found In Plant Parts Plants Leaves Coca, Dhatura , Belladona Unripe capsule Opium Seeds Colchicum, Nuxvomica Stem bark Cinchona, Kurchi Flowering buds Hyoscyamus Rhizome & roots Rauwolfia , Ipecac Whole aerial part Ephedra, Lobelia 🌳 🌿 🌹

6. Properties 1) Condition Most alkaloids are crystalline solids . Few alkaloids are amorphous solids ex. Emetine. Some are liquids that are either; Volatile ex. Nicotine & coniine. Non-volatile ex. Hyoscine & pilocarpine. 2) Color The majority of alkaloids are colorless but some are colored ex. Colchicine. Barberine are yellow. 3) Solubility Both alkaloidal bases and their salts are soluble in alcohol . Exceptions bases soluble in water: caffeine, ephedrine, codeine, colchicine.

7. Classification Of Alkaloids Sr.no Types Examples 1. True alkaloids N- In heterocyclic ring & originate from amino acid. Ex. Morphine, Atropine. 2. Proto alkaloids Contains nitrogen but not in ring. Ex. Mascaline , Colchicine. 3. Pseudo alkaloids Do not originate from amino acid. Ex. Terpenes & Steroidal alkaloids. 4. Peptide and cyclopeptide Ex. Sativanine -N, Sativanine -O.

8. Chemical Tests For Alkaloids Reagents Observation Hagers R. (Picric acid) ) Yellow precipitate Mayer’s R. (Pot. Mercuric Iodide Solution) Creamy precipitate Wagner’s R. (Pot. Triiodide solution) Reddish brown precipitate Dragendroff’s R. ( Pot.bismuth iodide solution) Reddish brown precipitate

9. Alkaloids Containing Drugs Pyridine & Piperidine (Tobacco, Areca, Lobelia) Tropane (Belladonna, Datura , Coca) Quinoline (Cinchona) Isoquinoline (Opium, Ipecac)

10. Indole ( Rauwolfia , Vinca ) Imidazole ( Pilocarpus ) Steroidal

11. Refferences Pharmacognosy and phytochemistry nirali prakashan , gokhale , purohit , kokate . A science of natural products ebook , book saga publication, Patil , Pandya.