Lecture 1 quality control of herbal medicine 5th year

1. Manufacturing and Quality of Natural
Medicinal Products
Course code 557
Dr. Mohamed Said
Lecturer of Pharmacognosy, Faculty of Pharmacy
Helwan University, Egypt

2. Method of evaluation
•Total degree (200 marks)
•100 (Final exam)
•40 (20 oral, 20 theoretical sheet)
•(60 practical "10 Lab book, 10 attendance,
40 Practical)

3. Quality Control Methods for Herbal
Medicines

4. Herbal drugs:
The term herbal drugs refers to the plant or the plant part that have been
converted into phytopharmaceuticals by means of simple processes involving
harvesting, drying and storage
Quality:
Defined as the status of a drug that is determined by identity, purity, content and
other chemical, physical or biological properties or by the manufacturing
processes
Quality control of herbal medicine:
Is a term that involves processes used in ensuring and maintaining the quality
and validity of manufactured herbal product

5. In order to use a plant drug as a herbal medicinal product or as a source of
a medicine i.e. an isolated purified compound, it is important to ensure that
[a] Correct plant is used
[b] The plant contains the required chemical constituents
[c] The constituents are present at the required level
[d] The type and level of constituents are reproducible from batch to batch of the
drug plant.
The term “Herbal quality" is used to denote a
combination of high percentage concentration of desired
compound [s] and a high total yield of that compound.

6. The factors which influence the quality of medicinal plants are:
❖ Identity of the plants
❖ Genetic factors
❖ Ecological factors
❖ Post harvest handling
❖ Methods of storage
❖ Environmental contamination

7. 1-Identity of the plants
• Botanical identification involves both macroscopically and microscopical inspection of the
raw materials.
Macroscopical
• According to the WHO , the macroscopical identity of the plant material is based on the
shape , size, color , surface, characteristic , texture , fractures , appearance of the out surface
of leaves, herbs , seeds, fruits , barks , stolon's , rhizomes and roots.
Literature report of poisoning and death resulting from the consumption of digitalis collected
by mistake for Comfery (Symphytum) plant, which highlights the importance of this simple
basic procedure of the quality procedure.

8. Microscopical
• Microscopic identification is based on the presence or absence certain key tissues, cells
and cell inclusions (eg. Trichomes, stomata, fibers, starch grains, calcium oxalate
crystals) which are diagnostic for a particular plant.
There have been numerous case reports of atropine poisoning arising from contamination of
herbal teas supposedly containing nettles or Burdock with deadly night shade (Atropa
belladonna ) leaves or roots.

9. 2- Genetic Factors:
• There are factors which relate to the inherent variability of individual organisms.
• Example:- in the opium poppy where the morphine content can vary from 3-12%. It is
possible to improve the quality of the plant by altering its genetic structure.

10. 3-Ecological factors:
• A variety of ecological factors can influence the quality of a medicinal plant by influencing
the Phyto mass or the amount of dry matter produced,
• Factors such as light which could increase or decrease the amount of flowers produced by
each plant could be significant.
• The others include temperature and water levels

11. 4- Post harvest handling:
• Post harvest enzyme activity: After harvesting
various biochemical processes continue for some
time, as the enzyme of the cell continue to function
normally and abnormally. The cells die slowly and
enzyme activity is no longer under any control.
• In drug plants where enzyme activity is damaging
the activity can be prevented by drying because
many of the most damaging enzymes are
hydrolysable requiring moisture for activity.

12. 5- Method of storage:
• Generally speaking, storage of medicinal plants is undesirable but largely
unavoidable Why? This is because dried drugs are extremely hygroscopic
and can absorb up to 15% by weight of moisture from the atmosphere.
Stabilization ?????????
6- Environmental contamination:
• Such contamination can take a number of forms e.g. microbial, insect or
heavy metal contaminations.

13. a. Organoleptic (sensory) characters.
• Macro and microscopical investigation
• There are certain numerical values which are used for identification purposes and
determining the purity and botanical sources.
• Also there are other microscopical counting techniques by which they can judge the quality
and the degree of its purity.
• Qualitative analysis of bioactive constituents including, qualitative chemical test and thin
layer chromatographic investigation of extracts of herbal drugs.
• The pharmacopoeias have set up the following procedures for detecting the quality
and uniformity of herbal drugs:

14. b. Proximate analysis including, ash values, extractive values, crude fiber, moisture content
and volatile oil content.
-Estimation of main active constituents including bitterness value, hemolytic activity,
foaming index, swelling index and tannins content.
-Potential contaminants including toxic botanicals, toxic botanicals microorganism and
microbial toxins, pesticides and fumigating agents, radioactivity, toxic metals, synthetic and
animal drug substances .

15. c. Physical identification of pure isolates such as, Melting point, , Boiling
point, Optical activity and Density.
d. Biological evaluation which helps in standardizing the strength of certain
drugs e.g. the cardiac effect of digitalis.
This procedure could be classified to the following standards or evaluation
methods:

16. Evaluation
methods
Structural
standards
Analytical
standards
Physical
standards
Biological
evaluation

17. Sampling
1. Powered drugs its components are 1 cm or less in any dimension
• If the total weight of the drug is less than 100 kg, the official sample should be at least
250g.
• If the total weight of the drug is more than 100 kg repeated samples not less than 110 of
packages were taken , mixed and quartered two quarters were rejected and the remaining
two quarters were combined , mixed and again subjected to quartering process in the same
manner until two of the quarters weigh at least 250g. which should constitute an official
sample

18. Sampling
2- Entire drugs which the component parts are over 1 cm in any dimension (taken by hand
from different parts of the container)
• If the total weight of the drug is less than 100kg the official sample should be at least 500 g.
• If the total weight is more than 100 kg repeated samples not less than 1/10 in number of
the packages are taken, mixed and quartered as before to get a sample 500 gm at least.
• When the total weight of the drug is less than 10 kg the final official sample should be at
least 125 gm.

19. Structural standards
 Organoleptic or sensory characters : It includes :
Color , Odor , which may be aromatic , rancid or characteristic , Taste
 Morphological characters
It is of diagnostic importance for the identification of entire drugs.
For example, Alexandrian senna pods could be differentiated from Indian Senna pods by
morphological means.

20. Structural standards
 Microscopical characters
They are very important for identification of drugs especially when they possess close
similarity with other drugs (e,g, other species of the same genus or substitutes having similar
external appearance .
 Microscopical numerical values:
These are numerical values used for determining the purity and botanical source of certain
powdered drugs. It includes:

21. Microscopical numerical values
Microscopical linear
measurements Ratio values
Palisade
Ratio
Stomatal
Number
Stomatal
Index
Veinlet
termination
Number
Vein-Islet
Number

23. Microscopical linear measurements
They are an important item in the total characters by which the drugs, especially powders,
are identified.

24. Ratio values
They are used for leaves only. They are fairly constant for the leaf of any particular plant.
Palisade Ratio
It is the number of palisade cells under one epidermal cell, using
4 contiguous epidermal cells for the count.

25. Stomatal index
Ratio values
Stomatal index = [S / S+E] x 100
Where S = number of stomatal cells in the same unit area
E = number of epidermal cells in the same unit area
It is the percentage which the number of stomata forms of the total number of
epidermal cells

26. Stomatal Number
Ratio values
It is the average number of stomata per square millimeter of
epidermis

27. Vein islet Number
Ratio values
• The small area of green tissues outlined by the veinlets is termed vein islets
• This value have been found to be constant for any given species and unaffected b the
age of the plant or the size of the leaves.
It the id number of vein islets square mm. This value
have been found to be

29. Veinlet termination Number
Ratio values
The number of Veinlet terminations per square mm
of leaf surface.
It can be used to distinguish between leaves of closely related species

30. Determination of cells per unit area:
It is a count of the number of cells of a certain type per unit area of a tissue.
It is applicable to layers of one cell thickness e.g. the sclerenchyma layer in different
cardamom varieties
Ratio values