This document provides information about alkaloids, including their definition, nomenclature, physiological action, occurrence, and isolation. It defines alkaloids as basic, nitrogen-containing organic compounds produced by various organisms. Alkaloids have diverse physiological effects and are commonly found in plants, where they serve protective and metabolic functions. Methods for isolating alkaloids from plant materials involve extraction with organic solvents followed by acid/base treatments and chromatographic separation to obtain pure alkaloids.

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2. Table of contents
i. Definition
ii. Nomenclature
iii. Physiological action
iv. Occurrence
v. isolation
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3. DEFINITION
Alkaloids are a class of basic , naturally occurring organic
compounds contains atleast one nitrogen atom
includes some related compounds with neutral and even
weakly acidic properties
are produced by large varieties of organisms including
bacteria, fungi , plants and animals
Example: quinine morphine ephedrine
Quinine Morphine Ephedrine
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4. nomenclature
 no unique method for naming alkaloids
 Trivial names should end by ‘ine’. These names may refer to :
• The genus of the plant , such as Atropine from Atropa belladonna
• The plants species , such as Cocaine from Erythroxylon coca
• The comman name of drug , such as Ergotamine from ergot
• The name of the discoverer , such as Pelletierine that was discovered
by Pelletier
• The physiological action , such as Emetine that act as emetic,
Morphine means God of Dreams act as narcotic.
• A Prominent physical character , such as Hygrine that is hygroscopic
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5. Prefixes and Suffixes
 Prefixes:-
 “Nor-” designates N-demethylation or N-demethoxylation , eg;-
Norpseudoephedrine and Nornicotine
 “Apo-” designates dehydration, eg;- Apomorphine
 “Iso-, pseudo-, neo-, and epi-” indicates different types of Isomers
Suffixes:-
 “-dine” designates Isomerism as quinidine and cinchonidine
 “-ine” indicates, in case of ergot alkaloids, a lower pharmacological
activity , eg:- Ergotaminine is less potent than ergotamine
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6. Physiological Action
 Alkaloids has a multifarious physiological activity profile. Some of the
recognized alkaloids with their typical physiological actions are :
 CNS activities :eg- caffeine, morphine
 ANS activities : eg- ephedrine, nicotine
 Antimalarial activity: eg- quinine
 Local anaesthetics: eg- cocaine
 Antibacterials: eg- berbrine
 Antipsychotics: eg- reserpine
 Antineoplastics: eg- vinblastine
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7. In plants :
 act as protective against insects and herbivores due to their bitterness and
toxicity
 are the final products of detoxification (waste product)
 Source of nitrogen in case of nitrogen deficiency
 act as growth regulators in certain metabolic systems
 utilized as a source of energy in case of deficiency in carbon dioxide
assimilation
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8. Occurrence
• Alkaloids are found;
 in certain types of fungi , such as psilocybin
 in animals, such as bufotenine in the skins of some toad
 in a number of insects, markedly ants
 many marine organisms also contain alkaloids
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9. occur in various parts of plants such as
 Nicotine is produce in the roots of tobacco plant which is then translocated to the leaves
 Morphine is obtained from the latex of opium poppy and also collected from fresh fruits
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 Quinine is the produced the from the bark of cinchona tree
 Colchicine is obtained from the seed and corm of colchicum.
Alkaloids are also found in the form of salts of some plant acids such as;
 Aconite alkaloids – with aconitic acid
 Cinchona Alkaloids – with quininic acid
 Opium Alkaloids – with neconic acid
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10. isolation
 We have two simple method;-
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Powdered material moistened with water
Separate organic layer containing alkaloid
Filter it
Extract with Organic solvent (Benzene, chloroform or acatone)
Collect the filtrate
Add water
Treated with lime
Pure alkaloid are separated by chromatographic techniques
Collect aqueous layer containing the alkaloid
Convert it into salt form
Add acid and water alkaloid
Reject Organic layer
Reject the aqueous layer containing impurities
Discard the powder material
Method - 1

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Reject aqueous layer
Treat with alkali and add organic solvent
Reject the organic layer containing impurities
Separate aqueous layer containing alkaloid
Add Acetone
Discard the powder material
Collect the filtrate
Filter it
Extract with water or Alcohol
Powdered material moistened with water
Treated with Acid
Pure alkaloid are separated by chromatographic techniques
Collect organic layer containing the alkaloid
Convert it into base form
Method - 2

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