Transcript Factor affecting Herb Quality

Factor affecting Herb Quality
 Comparing with conventional preparations, herbal
product represent a number of unique problems
when quality aspects are considered, these are
because of the nature of the herbal ingredients
present there in, which are complex mixtures of
secondary metabolites that can vary depending on
environment and genetic factor.
 The constituents responsible for the claimed
therapeutic effect are unknown or partly explained.
 Further complication use of combinations of herbal
ingredients as are use traditionally.
Quality standards of Herbal Products
1. Structural standard: comprises the structure
form of the crude drug which limits amount
of certain parts of organism concern
2. Analytical standards: constituents of material
3. Standards relating to physical constant, e.g.
density, refractive index ….. etc.
Factors relating to quality of Herbal drug
 To ensure reproducible quality of the herbal remedy, proper control of starting
material is almost essential.
 To control the quality of starting material, the following aspects
need to be considered:
1. Authentication and reproducibility of herbal ingredients by
macroscopic & microscopic characters and comparison with
authentic herb.
2. Inter/Intra species variation in plants.
3. Environmental factors.
4. Plant part used.
5. Time of harvesting.
6. Post harvesting factors
7. Contaminants of herbal ingredients.
8. Pesticides, fumigants and other toxic materials
Sampling procedures
1. Assessment of the quality of herbal drugs is
directly dependent on the selection of sample for
examination, the sample must be truly
representative of material undergoing analysis.
2. Because herbal materials are an aggregate of
individual plants and/or different parts of the
same plant and thus have an element of
heterogeneity, sampling should be carried out
with special care by personnel with the necessary
expertise.
3. Number of sample according to number of
package in shipment.
4. Sampling
material in bulk:
 Inspection each container for conformity
with pharmacopoeia monographs or other
requirements regarding packaging and
labeling
 Check integrity of outer package and note
any defect
 Damaged container sample d separately
 After opening container inspect the
follwing:
1. Organoleptic character (color, texture
& odor)
2. Presentation of material
3. Presence of admixtures, forign
matter, moulds or sign of decay
4. Presence of insects
5. Presence of packaging material
Morphological Examinations
1. Organoleptic evaluation
2. Macromorphological Evaluation
3. Cytomorpholgical evaluation
1. Organoleptic Evaluation
• Evaluation of drug by color, odor, size, shape,
taste, and special features including surface
characteristic (touch, texture,etc).
• Since the majority of information on the
identity, purity and quality of material can be
drawn from these observations, they are of
primary importance before any further
testing can be carried out
2. Macromorphological Evaluation
 Morphology is the study of the form of an object, whilst
morphography is the description of that form
 Interpretations of the morphological characteristics based
on different parameters, for all the plant organs give us a
first hand tool to know the features of whole or powdered
drugs and adulteration of commercial significance.
 It is most useful for only a part of plant to be used either
because the active constituent is found in a particular part
or because of economic consideration.
e.g. anthraquinone in bark of cascara
sagrada so there is little point in collecting
material other than bark
3. Cytomorphological Evaluation
 Examination of the cell form and arrangement of
different cells in a drug
 Cytomorphological characters play a major role in
drug identification
 The plant drugs contain some basic cell types e.g.
Parenchyma, collenchymas, sclarenchema …..etc
along with some cell inclusion characteristics i.e.
the presence of ergastic substances like starch,
calcium oxalate, silica ….etc.
 Analysis of the plant drugs based on the
distribution of these various cell types within
different organs is important to ensure the
identity and quality of herbal drugs.
Microscopical Evaluation
 Microscopical technique provide detailed
information about the crude drugs by virtue
of its main analytical uses.
 Used to visualize fine structure of minute
objects and thereby confirm the structural
details of the plant drugs under evaluation.
 These techniques can be used in the
determination of the optical as well as microchemical properties of the crude drug
specimens under study.
 Microscopical inspection of crude drugs from
plant origin is essential for identification of
the grounded on powdered material.
 It can provide supporting evidence which in
combination with other analytical parameters
can used to obtain full evidence for
standardization and evaluation of herbal drug
Instruments for microscopical study
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Camera-Lucida
Photomicrography
Modified light microscope
Polarizing microscopy
Phase contrast microscopy
Electron microscopy
Ultraviolet microscopy
Microscopical Methods
1. Microchemical testing of herbal drug: use different
chemical reagents, known as cleaning reagents or
bleaching agent,
e.g. phlorglucinol, Iodine water
2. Micro-chemical precipitation: when amount available
material is strictly limited, with a view to obtain
precipitate of characteristically formed microscope
crystals, used for alkaloid.
3. Microsublimation: applied to crude drugs that contain any
volatile crystalline principle, crude drug under study is
kept in small thin glass tube and sealed, the tube is
incorporate in a method of heating sample is sublimed
Development of Standardization
parameters
 Out of the numerous practical applications of
pharmacognosy, the great importance for the
pharmaceutical industry is in the evaluation of the crude
drug.
 This involve the determination of identity, purity and
quality.
 Purity depends upon the absence of foreign matter
whether organic or inorganic.
 Quality refers essentially to the concentration of the active
constituents in the drugs that make it valuable to medicine.
 By virtue of these constituents or components, the product
is used and it’s economic and commercial value is essential.
 Based on concentration and nature of the
constituents, a crude drug may conform to all
official standards of purity and be of good
quality.
 Naturally occurring inorganic or contaminants,
beside other contaminants affect purity of
crude drug which need proper assessment
and detection of different parameters indicate
their acceptability by criteria determined.
 Standardization involves adjusting the
herbal drug preparation to a defined
content of a constituent or a group of
substances with known therapeutic
activity by adding excipients or by mixing herbal
drugs or herbal drug preparations.
 Botanical extracts made directly from crude plant
material show substantial variation in composition,
quality, and therapeutic effects.
• Standardized extracts are highquality extracts containing consistent
levels of specified compounds, and
they are subjected to rigorous
quality controls during all phases of
the growing, harvesting, and
manufacturing processes.
 No regulatory definition exists for
standardization of dietary supplements. As a
result, the term “standardization” may mean
many different things.
 Some manufacturers use the term standardization
incorrectly to refer to uniform manufacturing practices;
following a recipe is not sufficient for a product to be
called standardized.
 Therefore, the presence of the word
“standardized” on a supplement label does not
necessarily indicate product quality. When the
active principles are unknown, marker
substance(s) should be established for analytical
purposes and standardization.
 Marker substances are chemically defined
constituents of a herbal drug that are
important for the quality of the finished
product.
 Ideally, the chemical markers chosen would
also be the compounds that are responsible
for the botanical’s effects in the body.
Types of standardization
• There are two types of standardization , In the first category,
“true” standardization, a definite phytochemical or group of
constituents is known to have activity.
Ex. Ginkgo with its 26% ginkgo flavones and 6%
terpenes is a classic example. These products are
highly concentrated and no longer represent the whole
herb, and are now considered as
phytopharmaceuticals. In many cases they are vastly
more effective than the whole herb.
• The other type of standardization is based
on manufacturers guaranteeing the
presence of a certain percentage of
marker compounds; these are not
indicators of therapeutic activity or
quality of the herb.
Standardization of Herbal drug
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Determination of solvent extraction values
Determination of Ash values
Determination of Total solids
Determination of Crude fiber
Determination of Moisture content
Determination of Essential oil in crude drug
Microbial infestations and their determination
Determination of Bitterness value
Determination of Hemolytic activity
Determination of Swelling index
Determination of Foaming index
Determination of Tannins
Determination of Arsenic & Heavy metals
Determination of Pesticides
Radioactive contamination
1. Determination of solvent extraction values
 Determine the amount of active constituents in a
given amount of medicinal plant material when
extracted with solvent.
 It is employed for that material for which no
chemical or biological assay method exist.
 As mentioned in different official books (BP).
 The determination of water soluble and alcohol
soluble extractives, is used as a mean of
evaluating crude drugs which are not readily
estimated by other means.
Method used
1. Determination of water soluble extraction.
2. Determination of alcohol soluble extraction
3. Solvent Hexane soluble extraction
4. Volatile ether soluble extraction
5. Nonvolatile ether soluble extraction
2. Determination of Ash values
 The ash of any material is composed of
their non-volatile inorganic components.
 Controlled incineration of crude drugs
result in an ash residue consisting of an
inorganic material (metallic salt and silica).
 The value varies within fairly wide limits
and therefore important parameter for the
purpose of evaluation of crude drugs.
 In certain drug, the percentage variation of the
weight of ash from sample to sample is very
small and any marked difference indicates a
change in quality.
 Unwanted parts of drugs, sometimes posses a
character that will raise the ash value.
 Direct contamination, such as by sand or earth, is
immediately detected by the ash value.
 Determined by 3 method:
Total Ash, Acid insoluble Ash , Water soluble ash
3. Determination of total solids
• Total solid is the residue obtained when the
prescribed amount of the preparation is dried
to constant weight under the condition
specified in method.
4. Determination of crude fiber
• Estimation of crude fiber denotes the
measurement of the content of cellulose,
lignin and cork cell in the plant tissue.
• Material is de-fatted and boiled with dilute
acid to eliminate the soluble material, dried
and weighed, excess of the crude fiber indirect
adulteration with woody tissue like kernels.
5. Determination of moisture content
 Moisture is an inevitable component of crude drugs, which
must be eliminated as far as practicable.
 The drying process should reduce the moisture content of
the drug below this critical, or threshold level.
 It is difficult to state a precise upper limit of moisture that
can be permitted in crude drug.
 USP and NF make no commitment in this regard in most
cases.
 Not only is the ultimate dryness of the drug is important,
equally important is the rate at which the moisture is
removed and the conditions under which it is removed.
 Method of determination:
Loss on drying, Azeotropic distillation, Karl Fischer
Azeotropic volumetric method
 Measurement of water or other volatile
constituents present in crude drug.
 Sample is distilled together with immiscible
solvent such as toluene, xylene.
 Water present in the sample is absorbed by the
solvent.
 Water and solvent is distilled together and
separated in the receiving tube on cooling.
 It is based on the fact that water and benzene,
toluene will form azeotropic mixture.
Apparatus used to determine water content by the
azeotropic method (dimensions in mm)
7. Determination essential oil in crude drug
 Volatile oils are characterized by their odor, oil-like
appearance and ability to volatilize at room
temperature.
 Because they are considered to be the "essence" of the
plant material, and are
often biologically active, they are also known as
"essential oils". The term
"volatile oil" is preferred because it is more specific
and describes the physical
properties.
 Only 2000 species are characterized by the volatile oil .
e.g. citrus family, parsley family and mints.
 Volatile oil comprise a diverse group of compounds,
embodying principally terpene, sesquiterpene and
diterpene.
 The terpene skeleton structure is subjected to many
modification, alcohol,aldhyde,ketone,phenol,ether,lactone
and ester structures are all found among different volatile
oils.
 Most volatile oil are isoprenoid compounds formed
through fusion of isoprene units.
 in order to determine the volume of oil, the plant material
is distilled with water and distillate is collected in graduated
tube, the aqueous portion separates automatically and
returned to distillation flask, volatile oil will float on top of
aqueous phase.
 Quality of oil determined by other analytical procedures.
Apparatus used to determine volatile oils
(dimensions in mm)
8. Microbial infestation and its determination
 Medicinal plant materials normally carry a
great number of bacteria and moulds, often
originating in soil and environment.
 While a large range of bacteria and fungi form
the naturally occurring microflora of herbs,
aerobic spore-forming bacteria frequently
predominate.
 Current practices of harvesting, handling and
production may cause additional
contamination and microbial growth. The
 Determination of Escherichia coli and moulds
may indicate the quality of production and
harvesting practices.
 Methods for decontamination are restricted. For
example, the use of ethylene oxide has been
forbidden within countries of the European
Union. Treatment with ionizing irradiation is also
forbidden or requires a special registration
procedure in some countries.
 In addition, the presence of aflatoxins in plant
material can be hazardous to health if absorbed
even in very small amounts. They should
therefore be determined after using a suitable
clean-up procedure.
Test for specific microorganisms
 The conditions of the test for microbial contamination
are designed to minimize accidental contamination of
the material being examined; the precautions taken
must not adversely affect any microorganisms that could
be revealed.
 Main contaminate are E.coli, Salmonella, Pseudomonas
aeruginosa, staphylococcus tested by different
subcultures method
 The total viable aerobic count of the material being
examined is determined, as specified in the test
procedure, for the plant material concerned using one
of the following methods: membrane-filtration, plate
count or serial dilution.
 The test procedure have to be validated on the microbial
strain as specified by WHO.
8. Microbial infestation and its determination
 Medicinal plant materials normally carry a
great number of bacteria and moulds, often
originating in soil and environment.
 While a large range of bacteria and fungi form
the naturally occurring microflora of herbs,
aerobic spore-forming bacteria frequently
predominate.
 Current practices of harvesting, handling and
production may cause additional
contamination and microbial growth. The
 Determination of Escherichia coli and moulds
may indicate the quality of production and
harvesting practices.
 Methods for decontamination are restricted. For
example, the use of ethylene oxide has been
forbidden within countries of the European
Union. Treatment with ionizing irradiation is also
forbidden or requires a special registration
procedure in some countries.
 In addition, the presence of aflatoxins in plant
material can be hazardous to health if absorbed
even in very small amounts. They should
therefore be determined after using a suitable
clean-up procedure.
Test for specific microorganisms
 The conditions of the test for microbial contamination
are designed to minimize accidental contamination of
the material being examined; the precautions taken
must not adversely affect any microorganisms that could
be revealed.
 Main contaminate are E.coli, Salmonella, Pseudomonas
aeruginosa, staphylococcus tested by different
subcultures method
 The total viable aerobic count of the material being
examined is determined, as specified in the test
procedure, for the plant material concerned using one
of the following methods: membrane-filtration, plate
count or serial dilution.
 The test procedure have to be validated on the microbial
strain as specified by WHO.
Limit specified by WHO for the microbial
contamination in Herbal drugs
 The WHO has specified total microbial contamination
limits for the medicinal plant materials.
 Different limits are set according to the use of the
material and the material itself.
 For contamination of "crude" plant material intended for
further processing
(including additional decontamination by a physical or
chemical process) the
limits, adapted from the provisional guidelines
established by an
international consultative group , are given for
untreated plant material
harvested under acceptable hygienic conditions:
- Escherichia coli, maximum 104 per gram;
- mould propagules, maximum 105 per gram.
•
For plant materials that have been pretreated (e.g. with boiling water as
used
for herbal teas and infusions) or that are used as topical dosage forms:
- aerobic bacteria, maximum 107 per gram;
- Yeasts and moulds, maximum 104 per gram;
- Escherichia coli, maximum 102 per gram;
- other enterobacteria, maximum 104 per gram;
- salmonellae, none.
• For other plant materials for internal use:
- aerobic bacteria, maximum 105 per gram;
- yeasts and moulds, maximum 103 per gram;
- Escherichia coli, maximum 10 per gram;
- other enterobacteria, maximum 103, per gram;
- salmonellae, none.
Presence and detection of Aflatoxin
 Aflatoxin is a toxin from Aspergillus flavus and
Aspergillus parasiticus having the chemical
formula C17H12O6, which may cause hepatic
carcinoma in human beings.
 The plant species may be contaminated with
this toxin.
 The test for aflatoxin as prescribed by WHO for
the herbal drugs is designed to detect the
possible presence of B1,B2,G1&G2 which are
dangerous contaminants in any plant material
of plant origin.
Detection of aflatoxin by TLC method