alkaloids chemical classification pharmacological classification Hegnaur's classification isolation of alkaloids purification of alkaloids

1. ALKALOIDS
Farman Ahmad
M.Pharm 1st Semester
Department of Pharmaceutical Sciences and Natural Products
Central University of Punjab, Bathinda

2. Content
 Introduction
Classification
Nomenclature
Extraction & Purification
References

3. Introduction
 The term alkaloid (alkali like) was coined by Carl F.W. Meissner in 1819, derived from the Arabic word “Al qualja” means
ashes of plants
 Group of natural occurring simple or complex nitrogen containing compounds
 Basic in nature
 Secondary metabolites abundantly found in plants and lesser extent in micro-organisms and animals
 Families rich in alkaloids are: Apocynaceae, Rubiaceae, Solanaceae, Papaveraceae
 In addition to carbon, hydrogen and nitrogen, may also contain oxygen,sulfur and other elements
 Usually derivatives of amino acids
 Produce various physiological function in organisms like- anti-bacterial, anti-inflammatory, analgesic, anti-neoplastic,
hypnotic, psychotropic, local anaesthetic etc

4. Classification
Classification of alkaloids may be:
 Hegnauer’s classification
 Chemical classification
 Pharmacological classification
 Taxonomical classification

5. Classification
Hegnauer’s classification
True Alkaloids:- They contain nitrogen atom in heterocyclic system and derived from amino acids
Example: Atropine, Morphine, Nicotine
Proto alkaloids:- They do not contain nitrogen atom in heterocyclic system but derived from amino acids
Example: Mescaline, Epinephrine, Ephedrine
Pseudo alkaloids:- They contain nitrogen atom in heterocyclic system but not the derivative of amino acids
Example: Caffeine, Theobromine, Coniine

6. Classification
 Chemical classification

7. Classification
Chemical classification

8. Classification
Pharmacological classification

9. Classification
Taxonomical classification
Alkaloids are classified based on biological sources. Examples: Quinine from the bark of Cinchona calisaya, Rauwolfia from
roots of Rauwolfia serpentina, Morphine from dried latex of Papaver somniferum, etc.

10. Nomenclature
There is no unique method for naming alkaloids
 Many individual names are formed by adding the suffix "ine" to the species or genus name For example, atropine is isolated
from the plant Atropa belladonna
 If several alkaloids are extracted from one plant then their names often contain suffixes "idine", "anine", "aline", "inine" etc.
 Naming alkaloids as the second Latin name the plant extract from him like Belladonine from belladonna
 Naming alkaloids according to the physiological effect (therapeutic) ex. Narcotic (Narcotine) , emetic ( emetine)
 Naming alkaloids according to the Discoverer ex. Pelletierine from Pelletier
 There are also at least 86 alkaloids whose names contain the root "vin" because they are extracted from vinca plants such
as Vinca rosea (Catharanthus roseus); these are called vinca alkaloids

11. Extraction & Purification
Stas-Otto method
Plant’s Material (Dried & Powdered)
Moist with water
Treat with lime
Extract with organic solvent
Filtration
Filtrate
Add water
Organic layer of alkali
Add water & Acid
Salt form in aqueous layer
Purification
Purified by chromatography

12. REFERENCES
1. Libretexts (2020) Alkaloids, Chemistry LibreTexts. Available at:
https://chem.libretexts.org/Courses/University_of_California_Davis/UCD_Chem_231A%3A_Methods_of_
Organic_Synthesis/Under_construction/1_Ideas/Alkaloids (Accessed: 05 October 2023).
2. (n.d.). Jiwaji University. http://www.jiwaji.edu/pdf/ecourse/pharmaceutical/Alkaloids-
Classification%20&%20Identification.pdf
3. Introductory Chapter: Alkaloids -Their Importance in Nature and for Human Life. (n.d.). IntechOpen -
Open Science Open Minds |IntechOpen. https://www.intechopen.com/chapters/66742
4. Classification of Alkaloids - Solution Parmacy. (n.d.). Solution
Parmacy. https://solutionpharmacy.in/classification-of-alkaloids/
5. Contributors to Wikimedia projects. (2001, October 24). Alkaloid - Wikipedia. Wikipedia, the free
encyclopedia. https://en.wikipedia.org/wiki/Alkaloid#In_medicine
6. Extraction Method of Alkaloids - Solution Parmacy. (n.d.). Solution
Parmacy. https://solutionpharmacy.in/extraction-method-of-alkaloids/

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