CLASSIFICATION OF ALKALOIDS EXTRACTION OF ALKALOIDS FUNCTIONS OF ALKALOIDS APPLICATIONS OF ALKALOIDS

1. (CLASSIFICATION,EXTRACTION,FUNCTIONS ,APPLICATIONS)
FACULTY NAME:SWATHI GARIGANTI
ASSISTANT PROFESSOR
SREE DATTHA INSTITUTE OF PHARMACY
SUBJECT:PHARMACOGNOSY&PHYTOCHEMISTRY-II
B.PHARMACY III-I SEMESTER

2.  CLASSIFICATION OF ALKALOIDS
 EXTRACTION OF ALKALOIDS
 FUNCTIONS OF ALKALOIDS
 APPLICATIONS OF ALKALOIDS

3. 3

4. CLASSIFICATION OF ALKALOIDS:
I. PHARMACOLOGICAL CLASSIFICATION:
Depending on the physiological response,the alkaloids are classified
under various pharmacological categories like
E.g.Narcotic analgesic: Morphine
Vasodilatation : Ephedrine, Ergonovine
Local anesthetic : Cocaine
Hallucinating : Mescaline, Psilocybin
II.TAXONOMIC CLASSIFICATION:
This method classifies the vast number of alkaloids based on their
distribution in various plant families,like solanaceous or
papillionaceous alkaloids.Preferably,they are grouped as per the name
of the genus in which they occur.
e.g.Ephedra,Cinchona.etc
4
Cinchona
Quinine

5. III-BIOSYNTHETIC CLASSIFICATION:
This method gives significance to the precursor from which the alkaloids
are biosythesized in the plant.
E.g.Ornithine- Tropane, Pyrrolidine, Pyrrolizidine.
Tyrosine-Benzyl isoquinoline.
Tryptophane- Indole alkaloids, Quinoline.
IV- CHEMICAL CLASSIFICATION :
This is the most accepted way of classification of alkaloids.The main
criteria for chemical classification is the type of fundamental (normally
heterocyclic)ring structure present in alkaloid.
Heterocyclic (True) alkaloids that are derived from amino acids and have
nitrogen in a heterocyclic ring. e.g Atropine.
Non-Heterocyclic(Proto) alkaloids that are derived from amino acids and
do not have nitrogen in a heterocyclic ring. e.g Ephedrine. 5
vinca Indole alkaloid
Atropine

6. NAME STRUCTURE
BIOLOGICAL
SIGNIFICANCE
Ephedrine Adrenergic agent- used for
asthma and hay fever
Colchicine
Relieves gout
Erythromycin
Antibiotic
(PROTO)ALKALOIDS:

7. No. HETEROCYCLE EXAMPLE
1. Pyrroleand Pyrrolidine
Hygrine, Stachydrine
2. Pyrrolizidine
Senecionine, Symphitine, Echimidine,
Seneciphylline

8. 3.
Pyridine and Piperidine
Lobeline, Nicotine, Piperine, Conine,
Trigonelline
4.
Tropane(piperidine/N-methyl-
pyrrolidine)
Cocaine, Atropine, Hyoscyamine, Hyoscine
5.
Quinoline
Quinine, Quinidine, Cinchonine,
Cinchonidine

9. 9. Indole or Benzopyrole Ergometrine, Vinblastine, Vincristine, Strychnine,
Brucine, Ergotamine, Yohimbine, Reserpine,
Serpentine, Physostigmine
10. Indolizidine Castanospermine, Swainsonine
11. Imidazole or glyoxaline Pilocarpine, Pilosine

10. 1 2 . P u r i n e
( p y r i m i d i n e / i m i d a z o l e )
C a f f e i n e , T h e o b r o m i n e
1 3 .
S t e r o i d a l ( s o m e
c o m b i n e d a s
g l y c o s i d e s ) *
C o n e s s i n e , S o l a n i d i n e
1 4 . T e r p e n o i d *
A c o n i t i n e , l y c a c o n i t i n e , A c o n i n e

11. 11

12. EXTRACTION OF ALKALOIDS:
 Extraction is based on the basicity of alkaloids and on the fact that they
normally occur in plants as salts (i.e.: on the solubility of bases and salts in
water and organic solvents).
 Herbs often contain other materials which can interfere with extraction
such as large amounts of fat, waxes, terpenes, pigments and other lipophilic
substances (e.g by forming emulsions) –avoided by defatting the crushed
herb (using petroleum ether and hexane.
 Extraction method normally depends on the raw material, the purpose of
extraction & the scale on which is to be performed.
 For research purposes: chromatography allows for quick and reliable results.
 If larger amounts of alkaloids need to be extracted, one of the following
methods can be used.
12
STAS OTTO PROCESS

13. STEP-II
 Organic solvent containing alkaloids (bases) is separated from
residue & concentrated by distillation under pressure if
needed.
 Solvent is stirred with an acidic aqueous solution: alkaloids go
into the solution as salts. Impurities remain in the organic phase.
 Aqueous solution of alkaloid salts is washed with an apolar
solvent (hexane).
 Alkalinized with a base using an organic solvent not miscible
with water.
13

14.  Alkaloids precipitate and dissolve in the
organicphase.
 Extraction of aqueous phase continues till all
alkaloids have moved into the organic phase
(tested when Mayer’s reaction on the aqueous
phase becomes negative).
 This purification step may be carried out in a
separation funnel or in centrifugal extractors.
STEP III:
 Organic solvent containing alkaloid bases is
decanted, freed from water traces (drying over
anhydrous salt e.g. sodium sulphate) and
evaporated under reduced pressure.
 A dry residue remains: total basicalkaloids.
14

15. EXTRACTION OF LIQUID ALKALOIDS:
II Methods possible:
 Plant powder is extracted directlywith acidified
water.
 Plant powder is extracted with acidified alcoholic or
a hydroalcoholic solution. This is then followed by
distillation under vacuum (eliminates that alcohol,
leaving behind and acidic aqueous solution of
alkaloid salts).

16. 16
PURIFICATION OF CRUDE EXTRACT
OF ALKALOIDS

17.  DIRECT CRYSTALLIZATION FROM SOLVENT: It is a very simple method of
isolation.
 STEAM DISTILLATION:-volatile liquid alkaloids-coniine,nicotine.
 CHROMATOGRAPHIC TECHNIQUES:TLC,HPTLC,COLUMN,GAS ION
EXCHANGE.
 GRADIENT pH TECHNIQUE:
1. crude drug +2%tartaric acid solution and extracted in benzene.-neutral/basic.
2. pH increased by 0.5 increments upto pH9.
3. Strongly basic Alkaloids.

18. FUNCTIONS OF ALKALOIDS:
 Protective against insect and herbivores due to their bitterness and toxicity.
 They are ,in certain cases,the final products of detoxification(waste product).
 Source of nitrogen in case of nitrogen deficiency.
 They some times act as a growth regulators,in certain metabolic systems.
 They may be utilized as a source of energy in case of deficiency in carbon dioxide assimilation.
18

19. APPLICATION OF ALKALOIDS:
In medicine
Medical use of alkaloid-containing plants has a long history, and, thus, when the first alkaloids were isolated
in the 19th century, they immediately found application in clinical practice. Many alkaloids are still used in
medicine, usually in the form of salts widely used including the following
E.g. Ajamaline(Alkaloid)-Anti-arrhythmic.
Reserpine-Anti-hypertensive.
Many synthetic and semisynthetic drugs are structural modifications of the alkaloids, which were designed to
enhance or change the primary effect of the drug and reduce unwanted side-effects.
For example, naloxone, an opioid receptor antagonist, is a derivative of thebaine that is present in opium.
19

20. In agriculture
Prior to the development of a wide range of relatively low-toxic synthetic pesticides, some alkaloids, such as salts
of nicotine and anabasine, were used as insecticides. Their use was limited by their high toxicity to humans.
Use as psychoactive drugs
Preparations of plants containing alkaloids and their extracts, and later pure alkaloids, have long been used as
psychoactive substances. e.g.Cocaine, caffeine, and cathinone are stimulants of the central nervous system.
Mescaline and many indole alkaloids (such as psilocybin, dimethyltryptamine and ibogaine) have hallucinogenic
effect.
Morphine and codeine are strong narcotic pain killers.
There are alkaloids that do not have strong psychoactive effect themselves, but are precursors for semi-synthetic
psychoactive drugs. For example, ephedrine and pseudoephedrine are used to produce methcathinone and
methamphetamine. Thebaine is used in the synthesis of many painkillers such as oxycodone.
20

21. REFERENCES
 C.K KOKATE :ALKALOIDS (VOLUME II )CHAPTER-
3:PAGE NO-3.1
 https://www.slideshare.net/Aschhipa/alkaloids-71239138
 https://www.slideshare.net/alexmpharm/alkaloids-134426257
 https://www.slideshare.net/priyankagoswami/alkaloids-27405638

22. THANK YOU