Pharmacognosy and phytochemistry of Vinca Alkaloids.

1. Vinca Alkaloids / Madagascar Periwinkle

2. Synonyms and Regional name:
• Vinca rosea
• Lochnera rosea
• Periwinkle
• Baramasi
• Madagascer periwinkle
• Sadaphuli
• Rattanjot Billaganneru
• Hindi- Sadabahar
• Beng.-Nayantara.

3. Introduction:
• Vinca alkaloids are obtained mainly from a
species of periwinkle known as Madagascar
Periwinkle. It is also known as “Sadabahar” or
“Sadaphuli”.
• Other species of periwinkle are also known to
contain vinca alkaloids.
• There are at least 150 alkaloids known to be
extracted from Vinca.
• Vinca alkaloids are chemically indole alkaloids
and are known to possess anti-cancer, anti-
hypertensive and anti-diabetic roles.

4. • Earlier this plant was used for antidiabetic action but
unable to confirm it.
• 1955-60 Canadian co worker reported its leucopenic
action in rat. It promotes discovery for anticancer
activity.
• Eli lilly company takes intensive investigation for
isolation of anticancer alkaloids.
• About 6 alkaloids has been found active but only 2
are commercially available( vincristine and
vinblastine).
• 1 gram of vinblastine from 500kg crude drug.
• 50 mg of vincristine from 1 tone of crude drug.

5. Biological Source
• Aerial parts of Catharanthus roseus formerly
known as Vinca rosea.
• Family: Apocynaceae

6. Geographical Source
• It is indigenous to Madagascar
and India.
• This plant is cultivated as an
ornamental plant.
• found in tropical and
subtropical regions like Africa,
Australia, Eastern Europe,
South Florida, India, Taiwan
and Thailand.

7. Morphology/Macroscopical
Characters
• A herbaceous subshrub, approximately 40-80
cm high.
• The leaves are oppositely arranged, oblong
with petiolate acute base.
• The flowers are produced throughout the
year, and are simple, generally 2-7 cm broad
with usually 5 petals joined together at the
base to form a tubule.
• The fruit is a divergent follicle.

8. Macroscopical characters:
(i) Type – Annular or perennial herb;
(ii) Size – 0.5 to 1 meter length;
(iii) Leaves – Ovate, oblong, glossy above glaucous
below;
(iv) Flowers – 2 to 3 in cymes, axillary and terminal
clusters. Bases on flower colour, three varieties are
known namely – alba-white, ocillata-white with pink
or carmine red eyes and roseus -with rose coloured
flowers.
(v) Fruit- a follicle, cylindrical and many seeded.
(vi) Taste – Bitter;
(vii) Odour – slight.

9. Microscopic Characters
Microscopical characters:
The transverse section of Vinca leaf
Lamina:
Upper epidermis:
Single layered with more or less rectangular cells, the outer walls of
which are circularized. Only covering trichomes are unicellular, long and
dagger shaped, warty and with a bulbous base. Sometimes very short
trichomes are also seen. A few stomata are seen on the upper
epidermis.
Mesophyll:
Mesophyll is differentiated into palisade and spongy parenchyma.
Palisade:
Single layered cells elongated and compact.
Spongy parenchyma:
5-9 layered, loosely arranged with intercellular spaces. Calcium oxalate
crystals of any kind are totally absent. Vascular strands are seen here at
times

10. Microscopic Characters
• Lower epidermis:
• Same as upper epidermis but the number of stomata
are more
• Midrib:
• Epidermal layers of lamina are continuous in the
midrib region also. Strips of collenchyma appear
below the upper epidermis and above the lower
epidermis. This is followed by cortical parenchyma. A
well developed vascular bundle is seen in the centre
of midrib.

11. Introduction to indole alkaloids
• Indole alkaloids are a class of nitrogen-containing
secondary metabolites that have a bicyclic
structure consisting of a benzene ring fused to a
pyrrole ring.
• They are derived from tryptophan amino acid or its
decarboxylation product, tryptamine and are
classified into different groups based on their

12. • Biogenetic precursor of all indole alkaloids is
the amino acid tryptophan.
• Indole alkaloids are a class of alkaloids
containing a structural moiety of indole; many
indole alkaloids also include isoprene groups
and are thus called terpene indole or
secologanin tryptamine alkaloids.
• Indole alkaloids are distinguished depending
on their biosynthesis.

13. • The two types of indole alkaloids are
isoprenoids and non-isoprenoids.
• Non-isoprenoid indole alkaloids derivatives
are the biogenic amines tryptamine and 5-
hydroxytryptamine (serotonin).
• Isoprenoid indole alkaloids: Isoprenoid indole
alkaloids include residues of tryptophan or
tryptamine and isoprenoid building blocks
derived from the dimethylallyl pyrophosphate
and isopentenyl pyrophosphate.

14. Biological activities of indole
alkaloids.
• Indole alkaloids are often characterized by their
potent biological activities,
• These are relevant to the field of medicine,
including anticancer, antibacterial, antiviral,
• antimalarial, antifungal, anti-inflammatory,
antidepressant, analgesic, hypotensive,
anticholinesterase, antiplatelet, antidiarrheal,
spasmolytic, antileishmanial, lipid-lowering,
• antimycobacterial, and antidiabetic activities
etc.

15. chemical constituents/Chemistry
• Vinca is rich in indole alkaloids particularly vincristine
and vinblastine. About 150 alkaloids reported.
• Coupling of indole alkaloids such as catharanthine
(indole) and vindoline (dihydroindoline or indoline)
produces the ‘‘binary vinca alkaloids’’ also called
bisindoles.
• Bisindole alkaloids: They are produced in living
organisms through dimerization of monomeric indole
bases.It contain conplex indole alkaloids.
• Contain nontryptophan derived part supplied by
mevalonic acid (C10 geraniol)

16. Other alkaloids
• Ajmalicine (Hypotensive)
• Serpentine (Hypotensive)
• lochnerine
• Tetrahydroalstonine
Best known oncolytic agents:
• vincristine (leurocristine)
• vinblastine (vinca leukoblastine)
• Vinleurosine or leurosine
• Vinrosidine or leurosidine

17. Semi synthetic alkaloids
• Vindisine (anti leukemic for children)
• Vinorelbine (newer orally active drug)
Monomeric alkaloids (indole):
• Catharanthine
• Lochnerine
Monomeric alkaloids (indoline):
• Vincoline
• vindolinine

19. Chemical constituents:
• 1. Indole and indoline alkaloids:
• (i) Ajmalicine
• (ii) Lochnerine
• (iii) Serpentine and
• 2. Tetrahydroalstonine:
• (i) Dimeric Indole bases of monoterpene type
• (ii) Vinblastine
• (iii) Vincristine.

20. Antidiabetic Activity:
• Vindogentianine, Vindoline, vindolidine,
vindolicine, and vindolinine represent four
new indole type alkaloids isolated from leaves
of vinca.

21. chemical Tests
• all general tests for alkaloids

22. Adulterants/Allied drugs/ Substitutes
• Other Catharanthus species such as
• C. longifolius,
• C. trichophyllus and
• C. lanceus are known to contain vindoline
type alkaloids.

23. Uses
• Vinca is useful in the herbal treatment of
lymphomas.
• Vinblastine is used for the treatment of
Hodgkin’s disease and non-Hodgkin’s
lymphomas, given by i.v. Route, available as
vinblastine sulphate.
• vincristine is used principally in the treatment
of acute lymphocytic leukaemia, available as
vincristine sulphate, given by i.v. route.
• Vincristine is superior than vinblastine but
more neurotoxin.

24. Uses:
• Antineoplastic (antimitotic= Cytostatic =
anticancer antitumor), act by arresting mitosis
at metaphase or by inhibiting amino acid
metabolism.
• In the treatment of Hodgkin’s disease.
• In the treatment of leukaemia in children,
lung cancer, cervical and breast cancer.
• Vinca is also used in hypertension.