content Deterioration of Herbal Drugs Primary Factors (Light, Moisture/ Humidity, Temperature and Air Oxidation) Secondary Factors Control Measures for Deterioration Adulteration of Crude Drugs Detection of Adulterants

1. DETERIORATION AND ADULTERATION
Assoc. Prof. Dr. Mostafa Mahmoud Hegazy PH.D

2.  content
 Deterioration of Herbal Drugs
 Primary Factors (Light, Moisture/ Humidity, Temperature and Air
Oxidation)
 Secondary Factors
 Control Measures for Deterioration
 Adulteration of Crude Drugs
 Detection of Adulterants

3. Medicinal plants Dr. Mostafa Hegazy
Deterioration of Herbal Drugs
- Several factors affect shelf-life of stored
crude drugs.
Secondary Factors for Deterioration
(living organism)
Primary Factors for Deterioration
(Physicochemical Factors)
1- Bacteria and Moulds
1- Light
2- Mites and Nematode Worms
2- Moisture/ Humidity
3-Insects/Moths
3- Temperature
4-Rodents
4- Air Oxidation

4. Medicinal plants Dr. Mostafa Hegazy
Primary Factors for Deterioration
1- Light:
In general, drugs should be protected by suitable light-
proof wrapping, by the use of amber ‫عسلي‬ colour glass
containers and/or stored in a dark place to prevent
photochemical reactions.
A- Light affect drug color:
1- Rose petals are red when fresh and changing to
brown on exposure to light.
2- Powdered rhubarb ‫الراوند‬ stored in clear glass jars
rapidly changes as the exposed surfaces turning from
yellow to more reddish colour.

5. Medicinal plants Dr. Mostafa Hegazy
B- Light affect drug activity and active
constituents :
1- Digitalis ‫اصبع‬
‫العذراء‬ leaves lose its
activity more rapidly in sun light.
2- Photo-decomposition occurs with
santonin, the principal constituents of
wormseed, which on exposure to light
darkens and eventually becomes black.

6. Medicinal plants Dr. Mostafa Hegazy
2- Moisture/ Humidity:
This amount of water is sufficient to activate the
enzymes present in some dried plant materials.
1- Digitalis ‫اصبع‬
‫العذراء‬ and bring about the
decomposition of the active glycosides.
2- Squill ‫بصل‬
‫العنصل‬ contains hygroscopic
mucilage and the powder therefore, if exposed to
the atmosphere, will pickup moisture and become
a sticky mass.

7. Medicinal plants Dr. Mostafa Hegazy
To overcome the effect of moisture/Humidity
1- drugs stored in airtight containers.
2- Stabilization of drug may be carried out:
a- Temporary stabilization: By storing the
drug in containers enclosing dehydrating agent
such as quick lime or calcium chloride.
b- Complete stabilization: By destroying
enzymes by subjecting the fresh drug to
alcohol vapour or immersing in alcohol.

8. Medicinal plants Dr. Mostafa Hegazy
3- Temperature
1- Many enzymatic changes more rapidly at the slightly
raised temperature up to about 45°C.
2- drugs containing volatile constituents in unprotected
structures, loose oil with an increase in temperature.
4- Air Oxidation
- Powered drugs are more liable to oxidative effects than
entire drugs?? as diffusion of oxygen is faster.
1- Fixed oils may be rancid e.g. Linseed oil ‫او‬
‫الزيت‬
‫الحار‬
‫الكتان‬and cod-liver ‫سمكة‬
‫القد‬ .

9. Medicinal plants Dr. Mostafa Hegazy
2- Volatile oils may be resinified e.g.
Turpentine ‫زيت‬
‫التربنتينه‬
‫او‬
‫الصنوبر‬ and oil of
Lemon.
3- Expecionally In some cases oxidative
changes are required, e.g. Frangula bark.
-these materials require storage in a well-
filled and airtight container.

10. Medicinal plants Dr. Mostafa Hegazy
Secondary Factors for Deterioration
- Living organisms usually develop in stored drugs where the
conditions are satisfactory for them.
1- Bacteria and Moulds
2- Mites and Nematode Worms
3- Insects/Moths
4- Rodents

11. Medicinal plants Dr. Mostafa Hegazy
Insect destroyed before storage by one
of the following methods:
1- Heat treatment: Exposing the drug to
temperature of 60-65 °C. This treatment
kills the insect eggs.
2- Fumigation: It includes use of volatile
insecticides in closed areas such as carbon
disulphide or T- gas (a mixture of 90%
Ethylene oxide and 10% carbon dioxide). It
has to repeat fumigation at intervals as it
dose not kill eggs.

12. Medicinal plants Dr. Mostafa Hegazy
3- Liming
- The drug is dipped in freshly
slacked lime or sprinkled with quick
lime.
- It is used for few drugs such as
Ginger and Nutmeg.
4- Freezing: By subjecting the drug
in refrigerator.

13. Medicinal plants Dr. Mostafa Hegazy
Control Measures for Deterioration
I- The container used for storage and its closure
1- must not interact physically or chemically
with the material within.
2- A well closed container
II- Storage area should be kept clean, dry and
prevent entrance of insect and rodent.
III- Periodic spraying with approved
insecticides will help to prevent the spread of
infestation.
- The material found to be contaminated is best
to be destroyed by burning.

14. Medicinal plants Dr. Mostafa Hegazy
Adulteration of Crude Drugs
Adulteration is substitution of the original crude drugs partially or fully with other
substances which is either free from or inferior in therapeutic and chemical
properties.This usually happens to rare or high priced drugs
- An adulterated drug does not comply with the official requirements of the
Pharmacopoeias
- Adulterant: The added substances used or adulteration
- Types of adulteration:
6. Inferiority.
1. Sophistication
7. Addition of worthless heavy materials
2. Substitution
8. Usage of Vegetative Matter from the Same Plant
3. Admixture.
9. Addition of powdered materials
4. Deterioration.
10. Addition of Synthetic Principles
5. Spoilage

15. Medicinal plants Dr. Mostafa Hegazy
1. Sophistication ‫التكلف‬ ‫الغش‬ ‫او‬ ‫المحاكاة‬
‫او‬ ‫الحقيقي‬
The addition of a material to any article
with intend to defraud
- Adulteration of ginger with starch,
capsicum for pungency and curcuma
for color
- Adulteration of beeswax with yellow
colored paraffin wax.
- Artificial invert sugar to adulterate
honey.

16. Medicinal plants Dr. Mostafa Hegazy
2. Substitution ‫االستبدال‬
The complete replacement of the genuine drug with a
different article.
Different methods used for adulteration may be
grouped as follows:
a) Substitution with Inferior Commercial Varieties
b) Substitution with Exhausted Drugs
c) Substitution by Superficially Similar but Cheaper
Natural Substances
d) Adulteration by Artificially Manufactured
Substitutes

17. Medicinal plants Dr. Mostafa Hegazy
a) Substitution with Inferior Commercial
Varieties
- Dog Senna (Cassia obovata) has been used to
adulterate Senna ‫السنامكي‬ (Cassia acutifolia).
- Japanese ginger (Zingiber mioga) to adulterate
medicinal ginger ‫الزنجبيل‬ (Zingiber officinale).
b) Substitution with Exhausted Drugs
- This practice is most common in case of volatile
oil containing materials like clove, fennel etc.,

18. Medicinal plants Dr. Mostafa Hegazy
c) Substitution by Superficially Similar but Cheaper
Natural Substances
- Peach and Apricot ‫مشمش‬ kernels for Almonds
- Dandelion ‫البرية‬ ‫الهندباء‬ for henbane ‫السكران‬ .
- Indian dill (Anetheum sowa)‫شبت‬ for European dill
(Anethum graveolens).
d) Adulteration by Artificially Manufactured Substitutes
- Artificial invert sugar for honey.
- Paraffin wax after yellow for bees wax
3. Inferiority
The same crude drug (not substituted) has low percentage
of active constituents e.g. Nux Vomica ‫المقئ‬ ‫الجوز‬ seeds
containing less than the official percentage of strychnine.,

19. Medicinal plants Dr. Mostafa Hegazy
4. Admixture ‫الخلط‬
Admixture is the addition of one article to another through
accident, ignorance or carelessness,
1- Adding other unwanted parts of the same plant as stems,
stalk and other aerial parts to the leaf drug or Inclusion of soil
on an underground organ.
2- the co-collection of two similar species, Collection of other
plants by mistake and ignorance of collection (Argel instead of
Senna leaves).
5. Intended Addition
I- Addition of worthless heavy materials
II. Addition of powdered materials
III. Addition of Synthetic Principles

20. Medicinal plants Dr. Mostafa Hegazy
I- Addition of worthless heavy materials:
- A large mass of stone has been found in the center of liquorice bales.,
- Pieces of limestone in Asafetida.
- Lead shots in Opium.
II. Addition of powdered materials:
These are powdered waste products of suitable color and density to adulterate
powder drug. e.g. powdered Olive stone are added to drugs like liquorices and
gentian or Hazel nut shells to Cinnamon,
III. Addition of Synthetic Principles
Sometimes to fortify inferior natural products, synthetic principles are added
Adding citral to oil of lemon; benzyl benzoate to balsam of Peru.

21. Medicinal plants Dr. Mostafa Hegazy
6. Usage of Vegetative Matter from the
Same Plant
This is done by mixing adventitious matters or
naturally occurring with the drug in excessive
amount or parts of plant other than that which
constitutes the drugs. e.g. Epiphytes,
Liverworts and lichens growing in bark
portion are mixed with Cascara or Cinchona or
Excessive amounts of stems in drugs like
Lobelia, Stramonium and buchu are
sometimes cut into short lengths and added to
the drug.

22. Medicinal plants Dr. Mostafa Hegazy
7. Deterioration (chemical and microbial)
I- Chemical deterioration is an impairment of the
quality of an article due to destruction of valuable
constituents by bad treatment or aging.
- Powdered Squill, hardened through absorption of
moisture.
II- Microbial deterioration This is a form of
deterioration in which the quality of the drug is
impaired or destroyed by the action of fungi,
bacteria, insects or rodents
e.g. Moldy Ergot and wormy Rhubarb.,

23. Medicinal plants Dr. Mostafa Hegazy
Detection of Adulterants
Procedures for detection of adulteration.
1- Establishing the Identity of the adulterant drug or substance.
2- Determination of the quality of the drug (Official specifications,
Pharmacopoeial or other).
Determination of the Adulterant Identity
6. Ultra Violet Light
1. Inspection of morphology
7. Processes of Assay
2. Histology and Microscopic Examination
8. Quantitative Microscopy
3. Microscopic Linear Measurements
9. Other Constants
4. Solubility and Physical Constants
10. Detection of Filth
5. Qualitative Chemical Tests

24. Medicinal plants Dr. Mostafa Hegazy
1. Inspection of morphology: Dog Senna
(Cassia obovata) has been used to adulterate
Senna (Cassia acutifolia).
2. Histology and Microscopic Examination:
Using various measurements as the Vein Islet
Number and Palisade Ratio for leaf drugs.
- inspection of type of trichomes and stomata
or Stomatal Index.
3. Microscopic Linear Measurements
The diameter of starch granules as well as the
diameter of Phloem fibres will assist to
differentiate between Cassia and Cinnamon
barks.

25. Medicinal plants Dr. Mostafa Hegazy
4. Solubility and Physical Constants:
in different organic solvents aids in the
examination of many oils and oleo-resins. Many
physical constants including Specific gravity,
Optical Rotation, Viscosity and Refractive
Index measured using specific instruments and
indicate adulteration especially for oils and fats.
5. Qualitative Chemical Tests: Many color tests
are specific for certain substances. e.g. Ammi
visnaga will give Rose Red color with KOH
while Ammi majus will not.

26. Medicinal plants Dr. Mostafa Hegazy
6. UV light: For identification of
Rhapontic which may be used to
adulterate Chinese Rhubarb.
7. Processes of Assay
Assays are conducted to determine
active constituents e.g. Alkaloidal
assays of belladonna or Volatile oil
estimation. The results obtained will
detect whether the drugs are
exhausted and or inferior quality.

27. Medicinal plants Dr. Mostafa Hegazy
8. Quantitative Microscopy
This includes
- counting the number of starch grains per
milligram, for detection of starches as adulterants.
- counting the number of characteristic Scleraids
per milligram, e.g., Olive stones and clove stalks,
- counting epidermal area per grams of powdered
leaf or measuring the total length of fiber per
gram,
All these quantitative methods are used if
chemical and physical methods are inapplicable.
Calculations of results are done by referring to
known constants or standards.

28. Medicinal plants Dr. Mostafa Hegazy
9. Other Constants
- Water Soluble Extractives, e.g. Liquorice and
Gentian; the water yield provide an easy assay
- Ash for determination of foreign inorganic matter:
The Acid insoluble ash gives an indication of
excessive earthy matter (consists mainly of silica).
- Crude fibers: Is used to detect excessive woody
materials, e.g., detection of Clove stalk in Cloves.
10. Detection of Filth
Filth consists of rodent feces and hairs as well as
insects and their parts. If present in a drug, render it
unfit for human use.

29. Herbal medicine Dr. Mostafa Hegazy