‫بسم هللا الرحمن الرحيم‬
Mai Mohammed Al-Oqail
‫مي محمد العقيّل‬
Email: maioqail@hotmail.com
Site: faculty.ksu.edu.sa/11982
Crud drugs :
Vegetable or animal drugs that consist of natural substances
that have undergone only the processes of collection and
drying.
Natural substances:
1- Plant origin: leaves, flowers, seeds and barks. Or
vegetable saps, extracts and secretions.
2- Animal origin: whole animals, glands or organs, extracts
and secretions.
To evaluate a crude drug:
Importance of evaluation of crude drugs:
1- Biochemical variation in the drugs
2- Deterioration due treatment and storage
3- Substitution and adulteration, as result of carelessness,
ignorance and fraud
Can be established by actual collection of the drug
from plants → +ve identified.
How to determine the origin of the samples:
1- "Drug gardens' established by institutions engaged in
pharmacognostical research.
2- Comparing unknown sample with
A- Published description drug
B- Authentic drug samples.
It is refers to the intrinsic value of the drug, i.e.,
the amount of medicinal principle or active constituents present.
How obtain high grade of quality?
I- Collection of the drug from the correct natural source at
the proper time and in proper manner.
e.g1., Opium
e.g 2., clove
II- Preparation of the collected drug by proper cleaning, drying
and garbling
III- Proper preservation of the cleaned, dried, pure drugs against
contamination with dirt, moisture, fungi, filth and insects.
Several problems not applicable to synthetic drugs
influence the quality of herbal drugs:
1-Herbal drugs are usually mixtures of many constituents.
2-The active principle(s) is (are), in most cases unknown
3-Selective analytical methods or reference compounds may
not be available commercially.
4-Plant materials are chemically and naturally variable
5-The source and quality of the raw material are variable.
6- The methods of harvesting, drying, storage, transportation,
and processing (for example, mode of extraction and
polarity of the extracting solvent, instability of constituents,
etc.) have an effect
The evaluation of a drug involves a number of methods:
Definition: The entire description of official crude drug monographs.
= Organs of sense = Macroscopic appearance of drug.
The majority of information on the identity, purity and quality of the
material can be drawn from these observations, they are of primary
importance before any further testing can be carried out
Authentic specimen of the material under study and samples of
pharmacopoeial quality should be available to serve as a reference.
This evaluation procedure provides the simplest and quickest means to
establish the identity and purity and thereby ensure quality of a
particular sample
1- Shape and size (for entire drugs not powdered).
Flowers:
Floral parts: stigmas, corollas, anther, ovary, receptacle.
Leaves and leaflets:
Length, width, apex, margin, base, venation,
the texture of the leaf and the hairs in upper and lower
surface.
The feel of the surface described as soft, hairy smooth.
.
The bark:
i- The barks occur in three shapes:
•Flat or curved pieces.
• Single quill.
•Double quills.
ii- Barks have two surfaces, an outer and inner.
iii- The inner surface is usually lighter in color than the outer surface
2- Odor and taste.
Odor:
1- distinct
2- indistinct
[Depend on the amount of volatile constituents present in drug].
General terms used in describing odor are:
1-aromatic,
2-balsamic,
3- spicy
Taste:
General terms used in describing taste are:
1- Acid (sour)
2- Saccharine (sweet): indicates sugar or sugar like substances
e.g., liquorice.
3- Saline (salty)
4- Alkaline
5- Bitter: indicates presence of substances such as bitter principle
e.g., glycoside, alkaloids.
6- Tasteless (all substances insoluble in the salive).
7- Distinctive sensations to the tongue:
a- mucilaginous and oily (soft feeling) e.g., linseed.
b- astringent (contraction of the tissues of the mouth) indicates
presence of tannin.
c- pungent (warm biting sensation) e.g., ginger.
d- acrid (irritant sensation) e.g., Aconite, coca.
e- nauseous (those tending to excite vomiting), Ipeca.
3- Color and external markings.
May help in revealing the nature of the herb.
1- White: e.g., starch, flours, gums)
2- Pale yellow (yellowish white) e.g., ginger, squill, white pepper.
3- Deep yellow: e.g., peeled liquorice, calumba, hydrastis.
4- Light pale brown e.g., nux vomica, fennel, coriander, anise.
5- Dark brown: e.g., cloves.
6- Dark reddish brown: cinchona, nutmeg.
7- Red: Kamala.
8- Pale green e.g., lobelia.
9- Greenish brown: most of the leaf herbs.
4- Fracture and internal color.
Dealing with microscopic
appearance of the herb in sectional
.view and in powdered form
Microscopical evaluation is useful in the study of:
1- Histologic elements of herbs.
2- Detection of adulterant.
3- Quantitative microanalysis of admixed or adulterated powders.
Histology:
refers to the character and arrangement of these tissues as
they are present in the herb.
Histologic studies :
1- Very thin transverse (radial) section
2- Longitudinal (tangential) sections (entire organ)
Powdered herbs posses very few macroscopic features of
identification outside of color, odor and taste.
For the identification of powdered crude drugs:
1- leaves:
a- Trichomes (glandular and nonglandular)
b- Crystals of calcium oxalate
c- Stomata
d- Epidermis cells, palisade,
e- Vessels
2- flower:
a- Trichomes (glandular and nonglandular)
b- Epidermis, stigma, anther.
c- Pollen grain
d- Volatile oil
3- Fruits and seeds:
Starch
Aleurone
Sclerenchyma
Vitta
Endocarp
Bark & wood:
Phloem, xylem
Trachedes, Parenchyma, wood
Parenchyma
Fibers, medullary rays, cork,
cambium.
In some cases, the drug may have
the same diagnostic element, they
are known as closely related
species. So, microscope is not the
method of choice
It is used to identify closely related species.
1-Microscopical linear measurement
Used only in Root Rhizomes Bark
E.g1., Different between Cinnamon ‫ القرفه السيالنيه‬as quill
and Cassia‫ القرفه الصينيه‬as flat
[Both have same diagnostic element].
So differentiate between both by:
Microscopical
measurement
1- Diameter
granules
linear
of
Cinnamon
starch < 8 μm
2- Width of phloem fiber
30 μm
Cassia
> 10μm
30-45 μm
Active constituent
Cinnamon
Cassia
Volatile oil
0.7-1% v/w
1-2%v/w
Cinnamic aldehyde
60-75%
Not less than 85%
Phenolics
4-10%
-
Eugenol
10%
-
Tast
Astringent
More astringent
Cost
Cheap
Cheaper
E.g2., Ipecacuanha
Starch granule
Rio Ipecacuanha
Cartagena Ipecacuanha
15 μm
17-20 μm
Why we need to differentiate between Rio and Cartagena Ipeca?
Because Rio Ipeca contains more emetine alkaloid.