The presentation covers microscopic characteristics of Rauwolfia. The transverse section, powder microscopy, micro-chemical tests and chemical tests of Rauwolfia are discussed in video lecture. It is useful for preparation of competitive examinations like GPAT.

1. Mr. Vipul. A. Sansare
M.Pharm (Pharmaceutics)
Contact No. :8692930764
Email :avipulsansare@gmail.com
Microscopy of Rauwolfia

2. Synonym: Serpentina root, Sarpagandha,
Indian snake root, chhotachand
BS: Dried roots and rhizomes of the
Rauwolfia serpentina
Family: Apocynaceae.
Collected in autumn from plants of 3 to 4 years
old.

3. Chemical constituents: Contain alkaloids (0.8
to 1.3 %).
Alkaloids like Reserpine, Ajmaline,
serpentine and rescinnamine.
Uses: Antihypertensive and tranquillizing
agent

4. T.S. of Rauwolfia
Medullary rays
Xylem fibres
Xylem vessels
Secondary phloem
Phelloderm
Cork
Phellogen

5. Powder microscopy
• Cork cells: Stratified isodiametric cells,
sometimes lignified.

6. • Parenchyma: Lignified, pitted, xylem
parenchymatous cells.
Contains starch grains

7. • Xylem fibres: Thick, lignified with pointed
or bifurcated ends.

8. • Xylem vessels: Lignified, oblique end walls.

9. • Calcium oxalate crystals: Prismatic
• Starch grains: Simple, spherical,
star shaped hilum.
• Stone cells are absent

10. Micro-chemical tests
Reagent Observations Characteristics
Phloroglucinol +
conc. HCl
Pink colour Lignified cork and
vessels
Iodine solution Blue colour Starch
Dil acetic acid Insoluble Calcium oxalate crystals
Dil. Hydrochloric
acid
Crystal soluble Calcium oxalate crystals
Sulphuric acid (60%) Needles of calcium
sulphate crystals
form on standing
Calcium oxalate crystals

11. Chemical tests
General chemical tests for alkaloids

12. Substitute/Allied drugs
I. Rauwolfia vomitoria (African Rauwolfia)
Five discontinued bands of schlerenchyma
Large vessels
II. Rauwolfia densiflora
Contain sclerenchyma
III. Rauwolfia tetraphylla
Uniform cork
Abundant sclerides and fibres
Absence of rescinnamine

13. ????
1. Rauwolfia serpentina can be distinguisg from the
other adulterants/ substitute of Rauwolfia species
by:
A. Presence of starch grains
B. Presence of calcium oxalate crystals
C. Presence of tricomes
D. Presence of sclereides

14. ????
1. Reserpine is derived from:
A. Squalene
B. Homoserine
C. Aspargine
D. Tryptophan and tryptamine

15. ????
1. Presence of which of the following characteristics
show that Rouwolfia serpentine is adulterated
with other species of Rouwolfia?
A. Presence of starch grains
B. Presence of calcium oxalate crystals
C. Presence of tricomes
D. Presence of lignified sclereides

16. ????
1. Reserpine is derived from:
A. Squalene
B. Homoserine
C. Aspargine
D. Tryptophan and tryptamine