Preparation method of crude drugs

1. PREPARATION OF CRUDE
DRUGS FOR
COMMERCIAL MARKET

2. 1. COLLECTION
 Crude drugs may be collected from:
• Cultivated plants
• Wild plants
 Collection of drugs from natural source is always reliable which
may or may not be the case when collected from wild source.
The most advantageous time of collection is during the that
period when the plant part containing constituting the drug is
highest in its content of active principles and when material
will dry to give the maximum quality and appearance.

3. Crude Drug Time of Collection
Flowers Should be collected prior to/ at time
of pollination
Fruits When fully grown, either fully ripe or
unripe
Roots and Rhizomes In the fall after the vegetative
process have ceased
Seed When fully matured .e. when most of
them have ripened and before the
fruits have opened
Barks In the spring before the vegetative
process have begun
Leaves or flowering tops When photosynthesis is most active,
time of flowering and before the
maturing of fruit and seed
Rules for Collecting Crude Drugs

4. 2. HARVESTING
 The mode of harvesting varies
with the drug being produced
and with the pharmaceutical
requirements of the drug.
 Tools for harvesting :
• Hand labour
• Mechanical devices: Pickers,
Mowers, Binders
3.DRYING
 It is a process by which
excessive moisture is removed
from any product which ensures
its good keeping quality.
 Advantages
• Bulk of drug is lost due to loss of
moisture
• Handling & transportation
becomes easy
• Cost of transportation becomes
less
• Packaging is easier
• Drying fixes the constituents and
facilitates grinding and milling

5. TYPES OF DRYING
1. Natural Drying
 Shade drying : employed when it is desired to retain
natural color of the drug.
 Sun drying : is adaptable to such drugs that are
favorably not affected by sunlight.
2. Artificial drying Most acceptable method when
temperature control and ventilation can be
monitored.

6. Crude Drug Method
Flowers Usually air dried or dried in
mechanical dryer at very low
temperature
Fruits or seeds Usually sun or shed dried
Roots and Rhizomes Usually sun dried and process takes
several weeks
Barks Based on constituents nature one of
any three methods (shade, sun or
artificial drying)
Leaves and other ground parts Dried at moderate temperature i.e.
40-60 provided that the active
principles are not destroyed at
elevated temperature
Rules in Drying Crude Drugs

7. 3.GARBLING
Removal of extraneous matter (undesired material)
from the collected plant parts is called as garbling In
some cases particles of irons are removed by using magnets
before it is grinded. Dirt and sand can be removed by
shifting / air current. In leaf drugs an excess of stem should
be removed.
4.PACKAGING
Packaging of drug depends upon final disposition if the drug.
Packaging of crude drug is necessary. It is not the part
of preparation of crude drug though. Packaging of a
crude drug depends upon the plant part or the active
constituents present inside in it.

8.  Precautions while packaging
 If the crude drug is hygroscopic in nature then it is packed in an air
tight container with a dehydrating agent.
 If fixed or volatile oil is to be packed, then air tight containers should
be used because air can recodification of volatile oils or of fixed oils.
 Herbs should be pressed by applying pressure converted into hand and
compact mass packed in burlap (jute) covering and properly sewn.
 Moisture proof containers with dehydrating agent packed in boxes and
barrel tin cans.
 Volatile oils should be sealed in well filled container. Air should be
replaced by some inert gas otherwise oxygen present in air can cause
oxidation of oil.
 Old packing is still in use for certain crude drugs. For example; Aloe
is packed in 55 gallon steel drums. Rose oil is packed in lead flasks.
Sarsaparilla roots are packed in large bales covered with cow hides.

9. Factors causing deterioration
Deterioration is majorly caused by two factors.
1. Primary factors
The detail of primary factors are given below;
Moisture
 Excessive moisture increases the weight of the crude drugs which decreases the percentage of active
constituents of crude drugs. It also causes fungal growth and enzymatic activity.
 In case of gums and resins and mucilage they are due to presence of moisture becomes sticky and
slimy because they reabsorb water very fast as compared to the bark and wood drugs which
reabsorbs little moisture.
 Leaves, herbs and root drugs if not properly packed reabsorb moisture up to 10 – 15% or even up to
30% of weight of drug.
 In certain drugs for example glycosides containing drugs such as digitalis, the drugs become
ineffective due to hydrolysis of glycosides.
 Excess of moisture is considered adulterant.
 Leaves and herb, these are bailed into solid compact mass.
 In order to save drug from moisture, for this it should be packed in air tight container with
dehydrating agent and periodically the agent is replaced with new when moistened.

10. Temperature
 Increase in temperature means increase in enzymatic activity and loss of
volatile component. Therefore, to prevent these warehouse should be cool
and drug must be stored at low temperature as possible.
 Sera, vaccine, hormonal precautions must be refrigerated at 6 ̊C.
Light
 Direct sunlight may cause decomposition of certain constituents for example
vitamins. Decolorization of drug or bleaching of crude drug for example leaf
and flower drug, cod liver oil.
 Polarize light produce degeneration rapidly and light reflected from plant
part is polarize to some extent. Therefore the drugs should be packed in light
resistant containers and warehouses should be dark.
Oxygen
 Presence of oxygen in the air causes oxidation, especially the enzyme oxidase
present inside is responsible.
 In case of fixed oil rancidity may occur. In case of drug having volatile oils,
they should be stored in sealed containers and air must be replaced by an
inert gas inside the cane. Warehouses should be dark

11. 2. Secondary factors
The detail of secondary factors are given below;
Microorganisms
 Wherever there is moisture there will be chance of microbial contamination.
To avoid from microbial contamination the crude drugs must be dried
immediately and use of antimicrobials.
Insects
 Insects those attack on the crude drugs belongs to three groups;
 Lepedoptera
 Coleoptera
 Dptera
 Most destructive insects such as moths which even in larval stage attack on
crude drugs and fruit drug material. They attack mainly on species i.e.
cinnamon, clove etc. the insects mainly attack on floral drugs.

12.  Methods to control deterioration
It can be controlled by managing;
 As low temperature as possible
 By storing the crude drugs at warehouses
 By protecting the drug from direct sunlight.
 By controlling over humidity and proper ventilation of air.
 There should be no hole in the walls, roofs and floor.
Deterioration & Adulteration of Crude drugs
 The drugs loses their quality either by deficiency of knowledge or carelessness of the
collector degrades the drug. Similarly, due to carelessness in drying and garbling.
Carelessness in drying and improper preservation may leads to accidental contamination.
 Moreover, odor or taste from other nearby stored drugs may contaminate, thus lowers the
quality of crude drugs.

13. Contamination vs. Adulteration
Contamination
 Contamination means impurity left by collector of admitted accidentally or by
carelessness.
Adulteration
 It means either addition of impurity or removal of all active constituents or a
part of active constituents. It also indicate the low grade drug or spoiled drug
with a definite intention of fraud. In legal sense the adulteration is
debasement of any article food or any other substance.
Example:
 Loss of caffeine by over roasting of coffee beans.
 Hardening of powdered squill due to absorption of moisture.
 Ergot contaminated by mold or any drug infested by insects.

14. Types of Adulteration
 The different types of adulteration are discussed below;
1. Inferiority
 It refers to a substandard drug or any other substance regardless to the cost. Any
substandard drug produce naturally.
 Example: Dried seeds of Nux-vomica containing less than 1.15% strychnine would
be of inferior quality and substandard drug.
2. Spoilage
 It is a condition of a food or a drug (crude) in which quality of the usefulness of the
materials has been destroyed by fungus or bacteria or molds to such an extent that
it is not fit for human use such drugs are legally considered as adulterated drugs.
3. Admixture
 Addition of one material to another either accidently or carelessly or ignorance. If
done intentionally then considered adulteration and specifically admixture.
Example: Addition of rodent feed matter into cardamom seeds.

15. 4. Substitution
 It can be defined as complete replacement of one article with another article,
is referred to as substitution.
Example: Replacement of fructose with glucose is a substitution adulteration.
5. Deterioration
 It means any impairment of quality either by removing (abduction) or by
destruction of valuable constituents by different means e.g. distillation, fungus,
insects, heat, moisture, aging etc.
6. Sophistication
 Addition of inferior material to another article with a definite intention of
fraud, is referred to as sophistication.
Example: Addition of wheat flour to ginger powder.
7. True adulteration
 Sometimes the adulteration is done intentionally for beneficial consequences,
such type of adulteration is called “True adulteration.”
Example: capsicum and turmeric are mixed together for pungency.