Practical Pharmacognosy prelab. Bark: Introduction - Cinchona, Cinnamon & Cassia.

1. Dr. Mahmoud Sallam
Assistant lecturer of Pharmacognosy,
Faculty of Pharmacy (Boys), Al-Azhar
University Cairo (Egypt).
Pre-lab. 1
BARK
▪ Introduction
▪ Cinchona – Cassia - Cinnamon

2. THE BARK
All tissues of the stem or the root outside the vascular cambium.

5. Young Stem:

6. VASCULAR CAMBIUM
CORK CAMBIUM
pith
Epidermis
Cortex
phloem
xylem
Young Stem:

7. Ph
Cortex
Xy
CORK CAMBIUM
VASCULAR CAMBIUM
Young Stem:

8. Ph
Cortex
Xy
CORK CAMBIUM
VASCULAR CAMBIUM
Old Stem:

9. Xy
Ph
Cortex
CORK CAMBIUM
VASCULAR CAMBIUM
1ry
2ry
Old Stem:

10. Ph
Cortex
Xy
CORK CAMBIUM
VASCULAR CAMBIUM
1ry
2ry
2ry
1ry
Old Stem:

11. Cortex
Ph
Xy
CORK CAMBIUM
VASCULAR CAMBIUM
1ry
2ry
2ry
1ry
1ry
2ry
Old Stem:

12. Cortex
Cork
Ph
Xy
1ry
CORK CAMBIUM
VASCULAR CAMBIUM
2ry
2ry
1ry
1ry
2ry
Old Stem:

13. CORK CAMBIUM
VASCULAR CAMBIUM
CORK
2ry CORTEX
1ry CORTEX
1ry PHLOEM
2ry PHLOEM
phelloderm
phellogen
phellem
PRECYCLE
BARK All the tissues outside the vascular cambium
2ry XYLEM
1ry XYLEM
Outer
Middle
Inner
BARK
Old Stem:

14.  SHAPES:
1. Flat: Quite flat and very thick (e.g., Quillaia).
2. Curved: Slightly concave on the inner side (e.g., Wild cherry).
3. Recurved: The concave side is the outer one (e.g., Pomegranate).
4. Channeled: Deeply concave on the inner side (e.g., Cassia).

15.  SHAPES:
5. Single Quill: One edge of bark covers the other (e.g., Cascara & Cinchona).
6. Double Quill: Both edges curved inward (e.g., Frangula ).
7. Compound Quill: Smaller quills are packed into bigger ones (Cinnamon).

16.  SURFACE:
1) Epiphytes
Lichens Liverwort Mosses
2) Lenticles:
Lenticles
3) Cracks & Fissures:
Cracks & Fissures
4) Wrinkles & Furrows:
Wrinkles & Furrows
5) Smooth:
Smooth

17. The Main Differences Between The Stem and Root Barks:
Item Stem bark Root bark
Outer surface:
Color: o Lighter than inner surface (due to
discoloration by sun light).
o Both inner and outer
surfaces have the same
color.
Epiphytes: o May be present. o Absent
Lenticels: o May be present. o Absent
o May be smooth, cracked, fissured or
furrowed.
o Scaly
Shape: o Thicker and may be flat, curved, or
quilled.
o Irregularly quilled or
twisted.

18. Decortication of Bark :
o Definition: Removal of the outer layers of the bark (cork, secondary cortex or whole
tissues outside the secondary phloem).
o Reasons of decortication:
1) Presence of low percentage of or no
active constituents.
2) Presence of undesirable constituents
or high percentage of tannins.

19. Stracture of the bark:
o The commercial bark may consist of all or some of the following tissues starting
from outside inward:
CORK CAMBIUM
CORK
SECONDARY CORTEX
3. PRIMARYCORTEX
5. PRIMARY PHLOEM
6. SECONDARY PHLOEM
phelloderm
phellogen
phellem
4. PRECYCLE
1. Rhytidoma
2. Periderm:
1, Rhytidoma
2, cork
3, cork cambium or phellogen;
4, phelloderm or secondary cortex;
5, periderm;
6, inner part of primary cortex;
7, groups of cortical sclerenchyma;
8, endodermis;
9, pericycle;
10, primary phloem;
11, secondary phloem;
12, cambium;
13, band of lignified fibers; 14, sieve
elements;
15, medullary rays.

20. CINCHONA BARK
‫الكينا‬ ‫قشر‬
Cinchona bark, Jesuit’s bark, Cardinal’s bark, Peruvian bark, Fever tree, Kina

21. o Dried root & stem barks of Cinchona succirubra (known as red Cinchona),
C. ledgeriana (known as grey cinchona) , C. calisaya (known as yellow cinchona)
& C. officinalis (known as pale cinchona).
o Family: Rubiaceae.
CINCHONA BARK
Origin
 Cinchona: o for the Countess of Chinchon, wife of the Viceroy of Peru.
 Quina: o from from Quechua word “kina = bark”.
 Succirubra: o with reddish-amber sap.
 Ledgeriana: o named after alpaca farmer Charles Ledger .
 Calisaya: o name of a member of a Bolivian tribe who told the Spanish about the
medicinal values of cinchona bark.
 Officinalis: o of the apothecaries, officinal medicines, sold in shops, officina.

22. Morphological Description
֎ Taste: bitter astringent.
ROOT STEM
Reddish brown
with grayish
lichens and
epiphytes.
Scaly, lichens
and other
epiphytes
are absent.

23. Phellogen
Phloem fibre
Medullary ray
Ideoblast
Secretory cell
Cortex
Phelloderm
Cork
Histological Description

24. Phellogen
Phloem fibre
Medullary ray
Ideoblast
Secretory cell
Cortex
Phelloderm
Cork
Histological Description

25. Microscopical Identification
2. Idioblasts containing microcrystals
of calcium oxalate
1. Spindle-shaped phloem fibres with
thick conspicuously striated walls
traversed by funnel-shaped pits.
3. Thin-walled cork cells.
4. Few small starch granules, simple
or rarely compound.

26. Microscopical Identification
2. Idioblasts containing microcrystals
of calcium oxalate
1. Spindle-shaped phloem fibres with
thick conspicuously striated walls
traversed by funnel-shaped pits.
3. Thin-walled cork cells.
4. Few small starch granules, simple
or rarely compound.

27. ACTIVE CONSTITUENTS
1. Quinoline Alkaloids: Cinchona contains about 20 alkaloids; the most important
alkaloids are:
a) Quinine. b) Quinidine. c) Cinchonine. d) Cinchonidine
2. Tannin (Condensed).
3. Bitter glycoside (Glycoside of Quinovic acid and quinovose sugar).

28. TESTS FOR IDENTITY
1. For alkaloids:
o Shake 0.1g powdered cinchona with 2 ml dil HCl, filter. Add to the filtrate a drop of
Potassium mercuric iodide (Mayer’s reagent) where a white precipitate is formed
immediately.
2. For tannins:
o Add 5% FeCl3 solution drop by drop and note the color produced. Condensed tannins
usually give a green Color.
o The test is best carried out by diluting 1ml of tannin extract in a test tube full of water
and then adding the FeCl3 solution.

29. TESTS FOR IDENTITY
3. Purified extract produces a strong blue fluorescence when dissolved in
oxygenated acids, e.g., sulfuric acid or acetic acid. The blue fluorescence is very
marked in extremely dilute solutions.
4. If powdered cinchona is slightly moistened with glacial acetic acid and heated in an
ignition tube, blood-red drops condense on the sides of the tube.

30. ACTION & USES
1. Bitter stomachic.
2. Tonic and astringent.
3. Quinine: anti-malarial.
4. Quinidine: antiarrhythmic.
5. Cinchonine & Cinchonidine: antirheumatic.

33. CASSIA
‫قرفة‬ ،‫دارسين‬ ،‫صيني‬ ‫دار‬
‫سيالني‬
‫ة‬
Chinese cinnamon
False cinnamon
CINNAMON
‫كاسيا‬ ‫قرفة‬ ،‫صيني‬ ‫قرفة‬
Ceylon cinnamon

34. Origin
CASSIA BARK CINNAMON BARK
Origin: o Dried bark of Cinnamomum
cassia.
o Dried inner bark of the shoots grown
on cut stock of Cinnamomum verum
(Cinnamomum zeylanicum) (Deprived
of most of its cortex).
Family o Lauraceae o Lauraceae
G.S.: o Vietnam, Indonesia and south
china, cultivated in other parts
of eastern China and Asia.
o It exist wild in Sri Lanka (Ceylon) and
southern India.
o The tree is also cultivated in
Madagascar, Jamaica and Brazil.

35. Morphological Description
CASSIA BARK CINNAMON BARK
Shape: o channeled, single quill. o Single, double or compound quill.

36. Decortication of Cinnamon Bark :
1. Harvesting 2. Processing 3. Decortication 4. Peeling & drying

37. Phloem
Cortex
Cork
Histological Description
Pericycle
CASSIA BARK CINNAMON BARK

38. Microscopical Identification
CASSIA BARK CINNAMON BARK
Cork
Starch
Sclereids
Starch
Sclereids
Fiber Fiber

39. Geographical origin: South of China Ceylon (Sri Lanka)
Cork & cortex: present absent
Fibers: Longer & Wider Shorter & thinner
Starch diameter: >10 m <10 m
Volatile oils: Up to 1.5% 0.5-1.2%
Eugenol: - Present
Cinnamic aldehyde
(irritant):
80% 65%
Coumarins: High amount Small amount
Taste: Pungent sweat
Chemical test: - Powder + KOH → needle
crystals of Potasium eugenate
CASSIA CINNAMON

40. $ 2099
/59g
$ 2048
/226g