The document discusses the standardization and preservation of herbal drugs, emphasizing the identification and quality assessment methods necessary for ensuring consistent herbal products. It details various standardization techniques, including macroscopic, microscopic, physical, chemical, and biological methods, along with specific tests for authenticity and potency. Additionally, it covers preservation techniques to maintain the integrity of herbal drugs during storage.

1. STANDARDIZATION AND
PRESERVATION
OF HERBAL DRUGS
BY
BOOBASH RAJ S
III M. Tech
Department of Biotechnology

2. HERBS:
Crude plant material such as leaves, flowers, fruit, seed, stems,
wood, bark, roots, rhizomes or other plant parts, which may be entire,
fragmented or powdered.
HERBAL DRUGS:
Finished labeled products that contain active ingredients such
as aerial or underground parts of plant or other plant material or
combinations thereof, whether in the crude state or as plant preparations

3. STANDARDIZATION OF HERBAL DRUGS :
Standardization of drug means confirmation of its identity and
determination of its quality and purity and detection of nature of
adulterant by various parameters like morphological, microscopical,
physical, chemical and biological observations.
HERBAL FORMULATION :
Obtained by subjecting herbal substances to treatments such as extraction,
distillation, expression, fractionation, purification, concentration or
fermentation. These includes powdered herbal substances extracts,
essential oils and expressed juices.

4. IDENTIFICATION OF MEDICINAL PLANTS

6. PROCEDURES FOR STANDARDIZATION OF HERBAL DRUGS:
In order to assure a consistent and acceptable quality herbal
product, care should be taken right from the identification and
authentication of herbal raw materials to the verification process of final
products.
The following parameters are recommended:
• Authentication.
• Physical parameters.
•Quantitative and qualitative analysis.
• Microbiological Contamination.
•Pesticide residue.
• Heavy Metal analysis.

7. DIFFERENT TECHNIQUES INVOLVED IN STANDARDIZATION
OF CRUDE DRUGS:
Macroscopic methods
Microscopic methods
Physical methods
Chemical methods
Biological methods

8. MACROSCOPIC METHODS:
The macroscopic study is the morphological
description of the plant parts which was carried out by a naked
eye placing the plant material on a white paper surface.
Organoleptic features such as shape, size, colour, odour, taste of
leaves, flowers, and fruits were evaluated.
MICROSCOPIC METHODS:
Microscopic techniques examine structural and
cellular features of herbs to determine their botanical origin. It
includes study of stomatal number, index, vein islets number,
types of trichomes, starch, grains and calcium oxalate crystals.

9. PHYSICAL METHODS:
It includes various parameterlike
Viscosity
 Melting point
 Solubility
Moisture content and volatile
matter
Specific gravity
 Density
Optical rotation
Refractive index
Bitterness value
 Hemolytic activity
 Swelling index
 Foaming index
Ash value
Astringency.

10. VISCOSITY:
Viscosity of a liquid is constant at a given
temperature and is an index of its composition. Hence it
can be used as a means of standardizing liquid drugs.
MELTING POINT:
In case of pure photochemical, melting points are
very important. The purity can be ascertained by the
melting point range. For example: colophony-75-800 c
SOLUBILITY :
The presence of adulterant could be indicated by
solubility studies. E.g. Asofoetida is soluble in carbon
dislphide.

11. MOISTURE CONTENT:
The moisture content of the drug should be minimized in order to prevent the
decomposition of crude drug either due to chemical change or microbial contamination.
The moisture is determined by heating drug at 1050 c in an oven. E.g. Aloe should have
the moisture content not more than 10%
OPTICAL ROTATION :
Optically active compound have the property of rotating the plane of polarized light.
Normally it’s determined by at 250 c using sodium lamp as light source. E.g. castor oil has
optical rotation from +3.5-60 c
REFRACTIVE INDEX:
When ray of light passes from one medium to another of different density then the ratio
of velocity of light in vacuum to its velocity in substance. It is constant for pure drug and
varied with wave length of incident of light, temperature and pressure. E.g. Castor oil has
refractive index 1.4-1.5

12. ASH VALUES AND EXTRACTIVES:
The residues remaining after
incineration is the ash content of drug. Total ash method is
used to measure the total amount of material remaining after
incineration. It is done by two ways- ACID insoluble ash,
WATER soluble ash. The total ash value, acid insoluble ash,
water soluble ash was found to be 11.75%, 7.45% and
7.85%. This percentage clearly indicates that the root is best
for drug action and effects.

13. BITTERNESS VALUE:
Medicinal plants having stronger bitter taste are therapeutically
used as appetizing agents. The bitterness is determined by
comparing the threshold bitter concentration of an extract
material with that of quinine hydrochloride.
Bitterness value in unit per gram = 2000*c
A*B
Where
A = concentration of stock solution
B = volume of test solution in tube with threshold bitter
concentration
C = quantity of quinine hydrochloride in the tube with
threshold bitter concentration

14. HAEMOLYTIC ACTIVITY:
Haemolytic activity of plant material is determined by comparison with that
of reference material, Saponin R, having haemolytic activity of 1000 units/g
Where haemolytic activity = 1000* a/b
1000 = defined haemolytic activity of saponin standard
a = quantity of saponin standard that produce total haemolysis (g)
b = quantity of plant material that produce total haemolysis (g)
SWELLING INDEX:
The swelling index is the volume of ml taken up by the swelling
of 1g of plant material under specified condition. It is
determined by addition of water in the test procedure of each
plant material

15. FOAMING INDEX:
Many medicinal plant material contain saponins that can cause a
persistent foam when an aqueous decoction is shaken.
Foaming index = 1000
a
Where a = the volume in ml of the decoction used for preparing
the dilution in the tube where foaming to a height of 1 cm is
observed.

16. CHEMICAL METHODS:
It comprises of different chemical tests and assays.
 The isolation, purification and identification of active constituents are chemical
methods of evaluation.
 Quantitative chemical tests shuchas acid vale, saponificationvalue etc., are also
coveredunderthis technique. Qualitative chemical tests are used in detection of
adulteration.
 The chemical evaluation also covers phytochemical screening carried out for
establishing chemical profile of a drug.

17. CHEMICAL EXAMINATION:
 Detection of alkaloids
Detection of carbohydrates and glycosides
 Detection of phytosterols
 Detection of fixed oils and fats
 Detection of saponins
 Detection of phenoliccompounds and tannins
Detection of protein and free amino acids
Detection of gums and mucilage
 Detection of volatile oils

18. BIOLOGICAL STANDRADIZATION:
Drug which cannot be assayed by chemical or physical means are evaluated by biological
methods. It is done by means of effect on living organism like Bacteria, Fungi or animal
tissues.
Types of Bioassay:
QUANTAL-It is all or none phenomenon.
GRADED - Based on observation that there is a proportionate increase in the observed
response with increase in concentration or dose.

19. PRESERVATION AND PROTECTION OF CRUDE DRUGS:
Storage represents the last stage of preparing crude drugs. drugs usually deteriorate along
the time of storage,
except in few cases e.g. Cascara and Frangula should not be used except after certain
period of storage.
Certain drugs as Nux vomica are hardly affected by storage.
Generally, changes that take place during storage of crude drugs are objectionable, e.g.
drugs containing volatile oils gradually lose their aroma.
Improper methods of storing and inadequate protection during storage can cause a
pronounced deterioration.
PRESERVATION CAN BE DONE BY FOLLOWING METHODS:
 Drying
 Lypholyzation (Freeze drying)
 Chemical drying using desiccators

20. DRYING:
Drying is a mass transfer process consisting of the removal of water or another
solvent by evaporation from a solid, semi-solid or liquid. This process is often used
as a final production step before selling or packaging products.
Drying is carried out either by
 NATURAL OR
 ARTIFICIAL METHODS.
1- Natural drying: this is accomplished by natural air in sun or shade.
2- Artificial drying: this is a rapid method done at well-controlled temperature
and is accomplished by:
• direct fire.
• Use of heated stones.
• Use of stoves.

21. Drying chambers:
This method provides a controlled process. Drying
chambers consist of closed space with several movable
screen trays, arranged so as to allow the circulation of
heated air. Its temperature and ventilation can be regulated
to suit drying of different organs.
REASONS FOR DRYING:
1. To help in their preservation.
2. To fix their constituents, by preventing reactions that
may occur in presence of water.
3. To prevent the growth of micro-organisms such as
bacteria and fungi.
4. To facilitate their grinding.
5. To reduce their size and weight.
6. Insufficient drying favors spoilage by microorganisms
and makes it possible for enzymatic destruction.