Quality Assurance of Herbal Formulations

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Quality Assurance of Herbal Formulations INTRODUCTION Herbal drugs have been used since ancient times as medicines for the treatment of a range of diseases. Medicinal plants have played a key role in world health. In spite of the great advances observed in modern medicine in recent decades, plants still make an important contribution to health care. Over the past decade, interest in drugs derived from higher plants, especially the phytotherapeutic ones, has increased expressively. 1 Herbs have created in interest among the people by its clinically proven effects like immunomodulation, adaptogenic and antimutagenic etc. 2 it is estimated that about 25% of all modern medicines are directly or indirectly derived from higher plant. According to the World Health Organization (WHO), because of poverty and lack of access to modern medicine, about 65-80% of the world's population which lives in developing countries depends essentially on plants for primary health care. 1 Also the overuse of synthetic drugs which results in higher incidence of adverse drug reactions, have motivated the humans to go back to nature for safer remedies. 2 India is the 8 th largest country having a total of around 47,000 plant species, out of which more than 7,500 species have medicinal values. Among these medicinal plants only 800 species are claimed to be in use and around 120 species are used in large quantities. 3 Currently the major pharmaceutical companies have demonstrated renewed interest in 1

Transcript of Quality Assurance of Herbal Formulations

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Quality Assurance of Herbal Formulations

INTRODUCTION

Herbal drugs have been used since ancient times as medicines for the treatment of a range of

diseases. Medicinal plants have played a key role in world health. In spite of the great advances

observed in modern medicine in recent decades, plants still make an important contribution to

health care. Over the past decade, interest in drugs derived from higher plants, especially the

phytotherapeutic ones, has increased expressively.1 Herbs have created in interest among the

people by its clinically proven effects like immunomodulation, adaptogenic and antimutagenic

etc.2 it is estimated that about 25% of all modern medicines are directly or indirectly derived

from higher plant.

According to the World Health Organization (WHO), because of poverty and lack of access to

modern medicine, about 65-80% of the world's population which lives in developing countries

depends essentially on plants for primary health care.1 Also the overuse of synthetic drugs which

results in higher incidence of adverse drug reactions, have motivated the humans to go back to

nature for safer remedies.2 India is the 8th largest country having a total of around 47,000 plant

species, out of which more than 7,500 species have medicinal values. Among these medicinal

plants only 800 species are claimed to be in use and around 120 species are used in large

quantities.3 Currently the major pharmaceutical companies have demonstrated renewed interest

in investigating higher plants as a source for new lead structures and also for the development of

standardized phytotherapeutic agents with proved efficacy, safety and quality.1 It is now

increasingly accepted worldwide that screening natural products is a more effective strategy for

discovering new chemical entities as natural product libraries have a broader distribution of

molecular properties such as molecular mass, octanol-water coefficient and diversity of ring

systems when compared to synthetic and combinatorial counter parts.3

The expanded use of herbal medicines worldwide has led to concerns relating to its safety,

quality and effectiveness. The quality control of herbal crude drugs and there formulations is of

paramount importance in justifying their acceptability in modern system of medicine. One of the

major problem faced by user industry is non- availability of rigid quality control profiles and

evaluationparametersforherbalformulations.4

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HISTORY

Herbal medicine is the oldest form of healthcare known to mankind. Herbs had been used by all

cultures throughout history. It was an integral part of the development of modern civilization.

The plants provided food, clothing, shelter, and medicine. Much of the medicinal use of plants

seems to have been developed through observations of wild animals, and by trial and error. They

methodically collected information on herbs and developed well-defined herbal pharmacopoeias.

Indeed, well into the 20th century much of the pharmacopoeia of scientific medicine was derived

from the herbal lore of native peoples. Many drugs commonly used today are of herbal origin.

Indeed, about 25% of the prescription drugs dispensed in the United States contain at least one

active ingredient derived from plant material. Some are made from plant extracts; others are

synthesized to mimic a natural plant compound.

The use of plants as medicine is older than recorded history. As mute witness to this fact

marshmallow root, hyacinth, and yarrow have been found carefully tucked around the bones of a

Stone Age man in Iraq. These three medicinal herbs continue to be used today. Marshmallow

root is a demulcent herb, soothing to inflamed or irritated mucous membranes, such as a sore

throat or irritated digestive tract. Hyacinth is a diuretic that encourages tissues to give up excess

water.

The first U.S. Pharmacopoeia was published in 1820. This volume included an authoritative

listing of herbal drugs, with descriptions of their properties, uses, dosages, and tests of purity. It

was periodically revised and became the legal standard for medical compounds in 1906. But as

Western medicine evolved from an art to a science in the nineteenth century, information that

had at one time been widely available became the domain of comparatively few. Once scientific

methods were developed to extract and synthesize the active ingredients in plants,

pharmaceutical laboratories took over from providers of medicinal herbs as the producers of

drugs. The use of herbs, which for most of history had been mainstream medical practice, began

to be considered unscientific, or at least unconventional, and to fall into relative obscurity.

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Early humans recognized their dependence on nature in both health and illness. Led by instinct,

taste, and experience, primitive men and women treated illness by using plants, animal parts, and

minerals that were not part of their usual diet. Physical evidence of use of herbal remedies goes

back some 60,000 years to a burial site of a Neanderthal man uncovered in 1960 .4 In a cave in

northern Iraq, scientists found what appeared to be ordinary human bones. An analysis of the soil

around the bones revealed extraordinary quantities of plant pollen that could not have been

introduced accidentally at the burial site. Someone in the small cave community had consciously

gathered eight species of plants to surround the dead man. Seven of these are medicinal plants

still used throughout the herbal world.4 All cultures have long folk medicine histories that

include the use of plants. Even in ancient cultures, people methodically and scientifically

collected information on herbs and developed well-defined herbal pharmacopoeias. Indeed, well

into the 20th century much of the pharmacopoeia of scientific medicine was derived from the

herbal lore of native peoples. Many drugs, including strychnine, aspirin, vincristine, taxol,

curare, and ergot, are of herbal origin. About one-quarter of the prescription drugs dispensed by

community pharmacies in the United States contain at least one active ingredient derived from

plant material. 5

Middle East medicine. The invention of writing was a focus around which herbal knowledge

could accumulate and grow. The first written records detailing the use of herbs in the treatment

of illness are the Mesopotamian clay tablet writings and the Egyptian papyrus. About 2000 B.C.,

King Assurbanipal of Sumeria ordered the compilation of the first known materia medica--an

ancient form of today's United States Pharmacopoeia--containing 250 herbal drugs (including

garlic, still a favorite of herbal doctors). The Ebers Papyrus, the most important of the preserved

Egyptian manuscripts, was written around 1500 B.C. and includes much earlier information. It

contains 876 prescriptions made up of more than 500 different substances, including many

herbs.5Greece and Rome. One of the earliest materia medica was the Rhizotomikon, written by

Diocles of Caryotos, a pupil of Aristotle. Unfortunately, the book is now lost. Other Greek and

Roman compilations followed, but none was as important or influential as that written by

Dioscorides in the 1st century A.D., better known by its Latin name De Materia Medica. This

text contains 950 curative substances, of which 600 are plant products and the rest are of animal

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or mineral origin.5 Each entry includes a drawing, a description of the plant, an account of its

medicinal qualities and method of preparation, and warnings about undesirable effects.

Muslim world. The Arabs preserved and built on the body of knowledge of the Greco-Roman

period as they learned of new remedies from remote places. They even introduced to the West

the Chinese technique of chemically preparing minerals. The principal storehouse of the Muslim

materia medica is the text of Jami of Ibn Baiar (died 1248 A.D.), which lists more than 2,000

substances, including many plant products. Eventually this entire body of knowledge was

reintroduced to Europe by Christian doctors traveling with the Crusaders. Indeed, during the

middle Ages, trade in herbs became a vast international commerce.

East India. India, located between China and the West, underwent a similar process in the

development of its medicine. The healing that took place before India's Ayurvedic medical

corpus was similar to that of ancient Egypt or China (i.e., sickness was viewed as a punishment

from the gods for a particular sin). Ayurvedic medicine emerged during the rise of the

philosophies of the Upanishads, Buddhism, and other schools of thought in India. Herbs played

an important role in Ayurvedic medicine. The principal Ayurvedic book on internal medicine,

the Characka Samhita, describes 582 herbs.8

By the Later Han Dynasty (25-220 A.D.), medicine had changed dramatically in China. People

grew more confident of their ability to observe and understand the natural world and believed

that health and disease were subject to the principles of natural order. However, herbs still played

an important part in successive systems of medicine. The Classic of the Materia Medica,

compiled no earlier than the 1st century A.D. by unknown authors, was the first Chinese book to

focus on the description of individual herbs. It includes 252 botanical substances, 45 mineral

substances, and 67 animal-derived substances. For each herb there is a description of its

medicinal effect, usually in terms of symptoms. Reference is made to the proper method of

preparation, and toxicities are noted.8

Since the writing of the Classic of the Materia Medica almost 2,000 years ago, the traditional

Chinese materia medica has been steadily increasing in number. This increase has resulted from

the integration into the official tradition of substances from China's folk medicine as well as from

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other parts of the world. Many substances now used in traditional Chinese medicine originate in

places such as Southeast Asia, India, the Middle East, and the Americas. The most recent

compilation of Chinese materia medica was published in 1977. The Encyclopedia of Traditional

Chinese Medicine Substances (Zhong Yao da ci dian), the culmination of a 25-year research

project conducted by the Jiangsu College of New Medicine, contains 5,767 entries.

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Here is a brief history of key dates in the development of herbal medicines: (8)

   

2800BC   First written record of herbal medicines, the Pen Ts'ao by Shen Nung

 

   

c400BC   First Greek herbal written; Hippocrates develops principles of diet, exercise and

happiness as the cornerstones of health

 

   

c100BC   First illustrated herbal produced in Greece

 

   

c50AD   Roman Empire spreads herbal medicine and commerce of plants around the

Empire

 

   

c200AD   Herbal practitioner, Galen, creates system for classifying illnesses and remedies

 

   

c500AD   Hippocrates' principles followed in Britain by Myddfai practitioners throughout

Saxon times

 

   

c800AD   Monks now pioneer herbal medicine with infirmaries and physic gardens at every

monastery

 

   

1100sAD   Arab world now major influence on medicine and healing practices.

Physician Avicenna writes the Canon of Medicine

 

   

1200sAD   Black Death spreads across Europe; 'qualified' apothecaries try bleeding,

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purging, mercury and arsenic to stem the epidemic with no more success than

traditional herbalists

 

   

1500sAD   Henry VII promotes herbal medicine in the face of the growing number of

untrained apothecaries and other 'medical practitioners' flourishing in London

Various Acts of Parliament passed to introduce some regulation of medical

practices including protection for 'simple herbalists' to practice without fear of

prosecution

 

   

1600sAD   Society sees the first two-tier health system emerge - herbs for the poor and

exotics (plant, animal or mineral extracts) or 'drugs' for the rich

Nicholas Culpepper writes his famous herbal: The English Physician, explaining

in simple terms the practice of herbal medicine

 

   

1700sAD   Preacher Charles Wesley advocates a sensible diet, good hygiene and herbal

medicine as the keys to a healthy life

 

   

1800sAD   Herbal medicines begin to be eclipsed by mineral-drug based treatments. With

powerful drugs such as calomel (mercury) and laudanum available over the

counter serious side effects begin to be documented.

Albert Coffin pioneers low-cost herbal remedies using plants from his native

America as well as European ones helping hundreds of working class people at

his north of England practice.

Burgeoning pharmaceuticals industry makes herbal medicine seem outdated.

National Association of Medical Herbalists founded to defend the practice. Later

to become the National Institute of Medical Herbalists

 

   

1900sAD   Medicinal herbals used extensively during World War I as drugs are in short

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supply.

Post war period sees enormous expansion in the international pharmaceuticals

industry and the discovery of penicillin

A handful of dedicated herbalists keep the tradition alive.

A Modern Herbal by Hilda Level is published.

Pharmacy & Medicines Act 1941 withdraws herbal practitioner’s rights to supply

patients with medicines. Public outcry ensures the Act is never enforced.

After much campaigning by the NIMH, the Medicines Act in 1968 reinstates

practitioners' rights and the British Herbal Medicine Association is founded.

The BHMA produce the British Herbal Pharmacopoeia.

Revised edition is published in 1990. Public concern starts to grow over the side

effects of the 'wonder drugs' of the 1950s and their impact on the environment.

 

   

2000AD    EU legislation advocates all herbal medicines should be subject to compulsory

clinical testing comparable to that undertaken for conventional drugs. Thus all

herbal medicines would be licensed.

UK government currently considering the possible impact and public perception

of this legislation.

 

Chapter - 2

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QUALITY

ASSURANCE

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Quality Assurance

Quality of a product is a very hot topic nowadays, and especially in the pharmaceutical

industry.Indeed, the regulatory authorities have paid special attention to quality in this

particular industry, due to the high risk of damage of life and health of patients possible, and

developed many guidelines to insure a sufficient level of quality. Quality is not any more

considered achieve able by strict adherence to, and verification of, specifications of

measurable parameters but has to be generated by a systematically planned and guided

process. Quality is not any more the sole responsibility of a central quality department but

requires the engaged participation of the entire work force.12

It is defined as the fulfillment all the requirements, legal and experience based, connected

with all aspects of manufacturing of high quality herbal medicinal products. It starts from the

beginning, the specification, processing and procurement of herbal starting material, follows

the procedure and quality considerations surrounding the intermediates and ends with

devising and monitoring the final production steps towards the final medicinal product.12

Quality assurance is therefore defined as a network. It encompasses the control and

documentation mechanism, which insure, that the multitude of regulations pertaining to and

used in practice of the pharmaceutical industry.

Assurance of product quality depends on more than just proper sampling and adequate

testing of various components and the finished dosage form. Prime responsibility of

maintaining product quality during production rests with the manufacturing department.

Removal of responsibility from manufacturing for producing a quality product can result in

imperfect composition, such as ingredients missing , sub potent or super potent addition of

ingredients , or mix up of ingredients ; mistakes in packaging or filling , such as product

contamination , mislabeling , or deficient package ; and lack of conformance to product

registration .Quality assurance personnel must establish control or checkpoints to monitor the

quality of the product as it is processed and upon completion of the manufacture .These begin

with raw materials and the component testing and include in-process , packaging ,labeling ,

and finished product testing as well as batch auditing and stability monitoring.13

In context with pharmaceutical industry quality assurance can be represented as:

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Quality assurance = GAP + GHP + GMP + GLP + other measures

GAP = Good agriculture practices.

GHP = Good harvesting practices.

GMP = Good manufacturing practices.

GLP = Good laboratory practices.

Good agriculture practices:

The guidelines for GAP of medicinal herbs is intended to apply to the growing and primary

processing of such plants traded and used in therapy . Hence, it applies to the production of

all plants materials used in the food, feed, medicinal, flavoring and perfume industries.

The main aim in this GAP is to ensure that the plant raw material meets the demand of the

consumer and the standards of the highest quality.11

Good harvesting practices:

The starting materials for all phyto medicines are plant drugs. Mostly parts or plant organs of

medicinally used species and usually in the dried form. According to WHO, there are 21,000

plant species as being medicinally used as plant drugs. Between 70%-90% of these are

commercially obtained by collecting the drugs in the natural habit. Among these only about

50 – 100 species are cultured by PTC technique.11

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Good manufacturing practices:

To deliver to the public life saving drugs of the highest quality and purity , the

pharmaceutical industry traditional has cooperate with FDA, even in recent years, when the

regulatory agencies have become increasingly restrictive.

This is a wide ranging concept concerning all matter that individually or collectively

influence the quality of product. It is the totally of the arrangement made with the object of

ensuring that product are of the quality required for their intended use.

The system quality assurance appropriate to the manufacturer of the pharmaceutical product

shall ensure that:

(a) The pharmaceutical are designed and developed in a way that takes account of the

requirements of GMP and other associated codes such as those of GLP and GCP.

(b) Adequate arrangements are made for manufacturer, supply and use of correct starting

and packaging materials.

(c) Adequate control on starting materials, intermediate products and bulk products and

other in process controls, calibration and validation are carried out.

(d) The finished product is correctly processed and checked in accordance with

established procedure.

(e) The pharmaceutical products are not released for sale product supplied before

authorized persons have certified that each production batch have been produced and

controlled in accordance with the requirements of the label claim and any other

provisions relevant to production, controlled and release of the pharmaceutical

products.11,20

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Good laboratory practices:

It is a quality system for testing laboratory. Implementation of GLP will result in reliable

data. Although US FDA GLP are applicable to non clinical laboratory studies that support or

are intended to support application for research or marketing permits for

Products regulated by the Food and Drug administration, but many elements of these GLP

are of universal application. These are two important functions every testing laboratory will

involve in via:-

Inspection and test

Sampling 12

Quality assurance of herbal drugs:-

Quality assurance of herbal products may be assured by proper control of the herbal

ingredients and by means of GMP.Some herbal products have many herbal ingredients with

only small amount of individual herbs being present. Chemical and chromatographic

tests are useful for developing finished products specifications. Stability and shelf life of

herbal products should be established by the manufacture .There should be no difference in

standard set for the quality of different dosage forms; such as tablet and capsule of herbal

remedies as well as from those of other pharmaceutical preparation.

In UK, for the licensed herbal remedies the European scientific cooperative for phytotherapy

(Escop) monographs are an important development. In India the majority of the herbal

remedies available are being marketed for a long time, in fact, for many products it may be

before D and C act 1948.The condition, in other developing countries for the sale and

production of herbal products are similar to UK.

Quality, safety and efficacy of herbal drugs have to ensure to provide sound scientific footing

to enhance consumer confidence and to improve business prospects for herbal medicines.11

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Quality assurance and quality control confusion

Quality Assurance: A set of activities designed to ensure that the development

and/or maintenance process is adequate to ensure a system will meet its

objectives.

Quality Control: A set of activities designed to evaluate a developed work

product.

QA activities ensure that the process is defined and appropriate. Methodology and standards

development are examples of QA activities. A QA review would focus on the process

elements of a project - e.g., are requirements being defined at the proper level of detail.

QC activities focus on finding defects in specific deliverables - e.g., are the defined

requirements the right requirements

Testing is one example of a QC activity, but there are others such as inspectionsThe

difference is that QA is process oriented and QC is product oriented. Testing therefore is

product oriented and thus is in the QC domain. Testing for quality isn't assuring quality, it's

controlling it.

Quality Assurance makes sure you are doing the right things, the right way.Quality Control

makes sure the results of what you've done are what you expected.

The term “quality assurance” and “quality control” is sometimes used

interchangeably, but there is an important difference. Quality control generally refers

to testing of raw material, packaging components, and final product for conformance

to established requirements .quality assurance is a term that includes quality control,

but has broader meaning to include procedures, personnel training, record keeping

and facility design and monitoring. The philosophy of a quality assurance program is

to build quality into the product, rather than to rely only on final product testingto cull

out defective product.16

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Chapter – 3

GENERAL CONCEPT

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GENERAL CONCEPT

The following concepts are important in the development and setting of specifications. They

are not universally applicable, but each should be considered in particular circumstances.

1) Characterization:-

Consistent quality for products of herbal origin can only be assured if the starting plant

materials are defined in a rigorous and detailed manner. Characterization of a herbal

substance/preparation or herbal medicinal product is therefore essential to allow

specifications to be established, which are both comprehensive and relevant.

a) Macroscopic/microscopic characterization:

Macroscopic characterizations of medicinal plant material are based on the shape, size,

color, surface characteristics, texture, fracture and appearance.

Color :-

The color is of use in indicating the general origin of the drug, e.g. material derived

from the aerial part of the plant is usually green and the underground plant materials

is usually devoid of green color.

Size :-

The length, width and thickness of the crude materials is of great importance while

evaluating a crude drug. A graduate ruler in millimeter is adequate for this

measurement.

Odor and Taste :-

Odor and taste of a crude material are extremely sensitive criteria based on

individual’s perceptions. The strength of the odor like weak, distinct, strong is first

determined and then odor sensation like musty, moldy, rancid, fruity, aromatic etc.are

determined.

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Surface characteristic – Texture and Fracture:-

The texture is best examined by taking a small quantity of material and rubbing it

between the thumb and forefinger, it is usually described as ‘smooth’, ‘rough’ ,

‘gritty’ . Touch of the material determines its softness or hardness. Bend and rupture

caused to the sample provides information of the brittleness and appearance of the

fractured plane as fibrous, smooth, rough, granular, etc.All this characteristic are

valuable in indicating the general type of material and the presence of more than one

component.11

Microscopic characterization is mainly depends on the parts of the plants such as

leaves, stems, flowers, fruits, seeds, barks, woods, underground drugs , entire

organisms, unorganized drugs.15

Leaf Constants

Palisade Ratio: It is defined as average number of palisade cells

beneath each epidermal cell. It can be determined with powdered

drugs.

Vein – islet number: It is defined as the number of vein –islets per

sq.mm of the leaf surface midway between the midrib and the margin.

Levin in 1929 determined vein- islet number of several dicot leaves.

Vein- termination number: It is defined as the number of vein let

termination per sq.mm of the leaf surface midway between the midrib

and the margin.

Stomatal number: It is average number of stomata per sq.mm of

epidermis of the leaf.5

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Stomatal index: It is the percentage which the number of stomata

forms to the total number of epidermal cells; each stoma being counted

as one cell. It is calculated by using the following equation:-

S.I. = S / E + S x 100

Where, S.I. = Stomatal index

S = Number of stomata per unit area

E = Number of epidermal cells in the same unit area 15

Trichomes:

These are another important diagnostic characters helpful in the identification of

drugs and detection of adulterants.Trichomes(fig1) are the tubular elongated or

glandular outgrowth of the epidermal cell.Trichomes is also called plant hairs.

Depending upon the structure and the number of cells present in trichomes, they

are classified as:15

Covering trichomes or non-globular trichomes or Clothing trichomes

Glandular trichomes

Hydathodes or special type of trichomes.15

Fig.1 Trichomes

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Stomata:

The primary and most important function of stomata(fig2)is gaseous exchange

and the secondary function is transpiration. However, it is generally observed

that stomata are abundantly present in dicot leaves. Dicotyledons stomata are

classified into following types depending upon the form and arrangement of

subsidiary cells.15

Paracytic or rubiaceos or parallel- celled stomata

Diacytic or caryophyllaceous or cross-celled stomata

Anisocytic or cruciferous or unequal-celled stomata

Anomocytic or ranunculaceous or irregular-celled stomata

Fig.2 Stomata

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Quantitative Microscopy:

Lycopodium spore method

It is an important analytical technique for powered drugs, especially when

chemical and other methods of evaluation of crude drugs fail as accurate measure

of quality. It is inexpensive technique with official status. Lycopodium spores are

very characteristics in shape and appearance and exceptionally uniform in size

(25µm). On an average, 94,000 spores per mg of powdered lycopodium are

present.15

N x W x 94,000x 100 / S x M x P = % Purity of Drug

Where,

N = number of characteristic structures (e.g. starch grains)in 26 fields

W =weight in mg of lycopodium taken

S = no. of lycopodium spores in the same 25 fields

M =weight in mg of the sample, calculated on basis of sample dried at 105 °C

P =2, 86,000 incase of ginger starch grains powder

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b) Phytochemical characterization:

Analytical data on constituents including constituents with known therapeutic activity as well

as compounds suitable as active markers or analytical markers include chromatographic

fingerprinting.

A chromatographic finger print profile represents qualitative/ quantitative determination of

various components present in a complex plant extract irrespective whether or not their exact

identity is known. In view of the enormous progress made during the four decades,

standardization of botanical raw material in respect of active ingredient or marker substance

poses no problem. The advances made in the separation science have given clear advantage

to the chromatographic methods over the conventional trimetric and spetrophotometric

methods. Thin layer chromatographic technique, the simplest least expensive, provides of

wealth of information on the composition of medicinal plant drugs and its preparations, thus

it is the technique of choice for the positive identification of the raw material. In view of the

TLC’s limitations in quantitative analysis, liquid chromatography, which provides

simultaneous separation and detection, is the technique of choice for quantitative

determination of active ingredients or marker substances. The HPTLC technique combines

selectivity and sensitivity thus providing stability indicating features.

Non-chromatographic Assays (Gravimetric, Titrimetric, and Spectrophotometric) Simpler

techniques that give a broader idea of different classes of compounds present in the herb or

the polyherbal product being tested. Example: Total Tannins, Total glycosides, etc. Hence

some of these assays are non-specific in their results yet valuable quantitative tools in the

absence of marker compounds.

Chromatographic Techniques (TLC, HPTLC, HPLC, GC): More specific, accurate and

versatile techniques for analysing phytoconstituents present in single herbs or mixtures

thereof. Usually require "marker compounds" or "reference standards" which can be

procured from specialized companies or generated by us.

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Depending on the availability of test methods, marker compounds and budget of the client, a

suitable technique or mix of methods can be employed to develop a standard testing method

for the study sample. This analytical protocol is then transferred to the client so that

subsequent tests can be performed at any other competent and equipped lab of their choice.11

c) Impurities:

Impurities can be classified as follows:

-impurities arising from starting materials (active substances, excipients) and containers

-process related impurities arising from the manufacturing process.

Contaminants, which are impurities such as heavy metals, pesticides, mycotoxins,

fumigants as well as microbial contamination, including those arising extraneous

sources, and radioactive substances, if relevant.

Degradation products, due to the particular nature of herbal medicinal product,

should primarily address toxicologically relevant impurities arising from

degradation of herbal substances/preparations.

Residual solvents, which are impurities arising from manufacturing processes.

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2) Design and development considerations:

The experience and data accumulated during the development of a herbal

substance/preparation or herbal medicinal product should form the basis for the setting of

specifications. In general, it is only necessary to test the herbal medicinal product for quality

attributes uniquely associated with the particular dosage form and the herbal substance or

herbal preparation present. For e.g. it may be possible to propose excluding or replacing

certain test on this basis some example is:

-reduced testing for pesticides residues where a herbal substance is grown under strict

organic cultivation without pesticides etc and potential contamination from adjacent

plantations has been eliminated,

-excluding or reducing tests for microbial limit in herbal preparations such as extracts or

tinctures depending on the ethanol content if justified by scientific evidence.

3) Pharmacopoeial tests and acceptance criteria:

The Indian Herbal pharmacopoeia contains important requirements pertaining to certain

analytical procedures and acceptance criteria that are relevant to herbal substances, herbal

preparation and their herbal medicinal products. Whenever they are appropriate,

pharmacopoeial methods should be utilized.

Drying and Storage of Plant Drugs

Drying

Drying consists of removal of sufficient moisture content of the crude drug so as to improve

its quality and make it resistant to growth of microorganisms. The process adopted for drying

is one of the parameters which affect the final quality of the drug. If enzyme action is to be

encouraged, slow drying at a moderate temperature is necessary. If enzymatic action is not

desired, drying should take place as soon as possible after collection. Drugs containing

volatile oils are liable to lose their aroma if not dried or if the oil is not distilled from them

immediately and all moist drugs are liable to develop mould. For these reasons, drying

apparatus and stills should be3 situated as near to the growing plants as possible. This has the

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further advantage that freightage is much reduced, as many fresh drugs contain a

considerable amount of water.

The duration of the drying process varies from a few hours to many weeks and in the case of

open- air drying depends largely on the weather.

Drying by artificial heat is more rapid than open-air drying and is often necessary in places

where humidity is high. Artificial heating may be done by continuous belt driers or by means

of open fires stoves or hot-water pipes. In all drying sheds there must be a space of at least 15

cm between superimposed trays and air must circulate freely17,18,19.

Storage:-

Preservation of the plant drugs needs sound knowledge of their physical and chemical

properties. Quality of drugs can be maintained, if these are preserved properly. All the drugs

should be preserved in well closed and, preferably in the completely filled containers. The

premises which are water-proof, fire-proof and preferably rodent-proof are ideal for storage.

Radiation due to direct sun-light also causes destruction of active chemical constituents,e.g.

ergot, cod liver oil and digitalis. Squill, when stored in powdered form becomes very much

hygroscopic and forms rubbery mass on prolonged exposure to air. Atmospheric oxygen is

also destructive to several drugs and hence these are filled completely in well closed

containers, or the air in the container is replaced by inert gas like nitrogen; e.g. shark liver

oil, papain, etc.17,18,19

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PESTICIDE RESIDUES AND MICROBIAL COUNT

Pesticide residue

The use of pesticide in the agricultural sector has greatly reduced the presence of insects,

fungi, and moulds in the plants. However, prolonged or excessive usage of pesticides on the

crop ultimately toxicants the entire plant material causing several health hazards. Limits for

pesticide residue should be established based on the recommendations of the Food and

Agriculture Organization (FAO) and the World Health Organization (WHO). These

recommended guidelines for food and animal feed provide the analytical methodology of

pesticide residues.17,18

Classification of pesticide

A classification based on the chemical composition and structure of the pesticide can be

made as follows:

Chlorinated hydrocarbons and related pesticides: Aldrin, benzene hexachloride(BHC)

or hexachlorocyclohesane(HCH) , chlordane, dieldrin, endrin, heptachlor

Chlorinated phenoxyalkanoic acid herbicides: 2,4-D; 2,4,5-T

Organophosphorus pesticides: Carbophenothion , chlorthion coumaphos, demeton,

dichlorvos, dimethoate, ethion, fenchlorphos.

Carbamate insecticides: Carbaryl

Dithiocarbamate fungicides: Ferbam, maneb, nabam, thiram.

Inorganic pesticides: Aluminium phosphide, calcium arsenate, lead arsenate

Pesticides of plant origin: Tobacco leaf and nicotine; pyrethrumflower, extract

Miscellaneous: Bromopropylate. Chloropicrin, ethylene dibromide.

Methods for the determination of pesticide residues

Chromatography and other procedures are the most successful when determining pesticide

residues. Samples are extracted by a standard procedure, impurities are removed by partition

and adsorption and the presence of a moderately-broad spectrum of pesticides is measured in

a single determination. However, these techniques are not universally applicable. As a result

of limitations in the analytical technique and incomplete knowledge of pesticide interaction

with the environment, it is not yet possible to apply an integrated set of methods which will

satisfy all situations.17,18

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Maximum limit of residues for medicinal plant materials:

The maximum residue limit(MRL) for medicinal plant materials, including their preparations

such as tinctures, extracts, oils etc. should be defined within the limits of pesticide residue set

by the FAO/WHO Codex. Since the medicinal plant materials are usually taken in much

smaller quantities than other food products, the MRL can be calculated based on the

maximum acceptable daily intake (ADI) of pesticides for humans and the maximum daily

dose (MDD) of the medicinal plant material.

Where the nature of the pesticide to which the plant material has been exposed is unknown ,

it is necessary to determine only the content of total chlorine and to base the calculation on

the MRL of the most toxic chlorine- containing pesticide.18,19

4) Periodic/Skip testing:

Periodic or skip testing is the performance of specified tests at release on pre-selected batches

and/or at predetermined intervals, rather than on batch to batch basis. This represents a less

than full schedule of testing and should therefore be justified and presented to the regulatory

authority prior to implementation .This concept may be applicable to , for

example ,dissolution ,residual solvents, and microbiological testing,e.g.,for solid dosage

forms. This concept may therefore sometimes be implemented post approval in accordance

with GMP and approval by the regulatory authority.

5) Release versus shelf life acceptance criteria: The concept of different

acceptance criteria for release versus shelf life specifications applies to herbal medicinal

products. This concept can also apply in exceptional cases to herbal substances and herbal

preparations, if justified. It pertains to the establishment of more restrictive criteria for the

release of a herbal medicinal product than are applied to the shelf life .Example where they

are applicable include assay or impurity (degradation product) levels.

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6) In process tests:

In-process tests are tests, which may be performed during the manufacturing of either the

herbal preparation or herbal medicinal product, rather than as part of the formal battery of

tests which are conducted prior to product release. In-process tests, which are used for the

purpose of adjusting process parameters within an operating range, e.g., hardness and

friability of tablet cores, which will be coated, are not included in the specification. Certain

tests conducted during the manufacturing process, where the acceptance criteria are identical

to or tighter than the release requirement, (e.g. of a solution) may be used to satisfy

specification requirements when the tests is included in the specification.

7) Reference standard:

A reference standard, or reference material, is a substance prepared for use as the standard in

an assay, identification, or purity test. In the case of herbal medicinal products, the reference

standard may be a botanical sample of the herbal substance, a sample preparation e.g. extract

or tincture or a chemically defined substance e.g. a constituents with known therapeutic, an

active marker or an analytical marker or a known impurity. The composition of reference

standards of herbal substance and herbal preparations intended for use in assays should be

adequately controlled and the purity of a standard should be measured by validated

quantitative procedures.

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Herbal samples

If the herbal substance is not described in the European pharmacopoeia or in another

pharmacopoeia of a member state , a herbarium sample of the whole plant or part of

the plant, if the whole plant is a tree etc.,must be available.

To prepare a pooled sample for herbal drugs is very difficult as most of the foreign matters

are adhered to the medicinal plant material, which are intrinsically non-uniform. That is why

it is crucial that the size of the sample should be sufficiently large to be considered as a true

representative. In the case of whole drug, a weighed quantity (50-500gm) according to the

type of the drug is taken as sample.11

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Chapter 4

HERBAL SUBSTANCES

AND

HERBAL PREPARATIONS

Herbal Substances

These are all mainly whole, fragmented or cut plants, plant parts, algae, fungi, lichen, in an

unprocessed, usually dried form but sometimes fresh. Certain exudates that have not been

subjected to a specific treatment are also considered to a herbal substance. Herbal substances

are precisely defined by the plant part used and the botanical name according to the binomial

system (genus, species, variety and author).

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Herbal substances are a diverse range of botanical materials including leaves, herbs, roots,

flowers, seeds, bark etc.A comprehensive specification must be developed for each herbal

substance even if the starting material for the manufacture of the herbal preparation . In the

case of fatty or essential oils used as active substances of herbal medicinal products a

specification for the herbal is required unless justified. 25

Identification Tests:

Foreign matter:

Foreign matter in herbal drugs consists of either parts of medicinal plant other than those

named with specified limit; or it may be any organism, part or product or an organism. It may

also include mineral admixtures not adhering to the medicinal plant material e.g. soil, stones,

dust etc.Medicinal plant material should be entirely free from visible sign of any

contamination.11

o Sampling :

To prepare a pooled sample for herbal drugs is very difficult as most of the foreign matters

are adhered to the medicinal plant material, which are intrinsically non-uniform. That is why

it is crucial that the size of the sample should be sufficiently large to be considered as a true

representative. In the case of whole drug, a weighed quantity (50-500gm) according to the

type of the drug is taken as sample.

o

oProcedure:

The specific quantity of plant material as mentioned below is spread on a thin layer of paper.

To sort onto different groups of foreign matter it has to be examined either by visual

inspection or by using magnifying lenses (6x or 10x) and the foreign matter are picked out

and the percentage is recorded. The remainder of herbal drug sample is passed through 250

mesh sieve to make it free from dust, which is regarded as mineral admixture. The content of

each group of foreign matter should be calculated in gram per 100gm of air dried sample.

Unless otherwise specified the quantities of samples to be taken into account to determine the

foreign matters of any herbal drugs as specified WHO are as follows:

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Leaves, flowers, seeds and fruits - 250 gm

Roots, rhizomes and barks - 500 gm

Cut medicinal plant material - 50 gm

Total ash:

Ashing involves an oxidation of the components of the product. A high ash value is

indicative of contamination, substitution, adulteration or carelessness in preparing the crude

drug for marketing. Total ash is designed to measure the total amount of material produced

after complete incineration of the ground drug at as low temperature as possible (about

450°C) to remove all the carbons. At higher temperature, the alkali chloride may be volatile

and may be lost by this process. The total ash usually consists of carbonates, phosphates,

silicates and silica which include both physiological ash - which is derived from the plant

tissue itself and non-physiological ash - which is the residue of the adhering material to the

plant surface, e.g., sand and soil.11

While determining the total ash very high temperature (>600°C) may result in the conversion

of carbonates to oxides. I n that cases re-carbonation may be done by treatment of the ash

with a solution of ammonium carbonate and further re drying to constant weight which give

the carbonated ash. The similar treatment with dilute H2SO4 results in sulphated as where the

oxides are converted to sulphates. When the same treatment is done by dilute HN03 results in

nitrated ash. As recommended by the World Health Organization the total ash can be

determined by the following procedure:

Place about 2-4 g of ground air dried material, accurately weighed in a previously ignited and

tared crucible of platinum or silica. Spread the material in an even layer and ignite it by

gradually increasing the heat to 500-600°C until it is white, indicating the absence of

carbon.11

Cool in a dessicator and weigh. If carbon free ash cannot be obtained in this manner, cool;

the crucible and moisten the residue with about 2 ml of water or a saturated solution of

ammonium nitrate. Dry on a water bath, then on a hot plate and ignite to constant weight.

Allow the residue to cool in a suitable dessicator for 30 minutes, and then weigh without

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delay. Calculate the content of total ash in mg/g of the air dried material. Indian

Pharmacopoeia 1996 prescribes suitable method for the determination of ash values. Method

I is for crude vegetable drugs and Method II for other substances:

oMethod I

Unless otherwise stated in the individual monographs, weigh accurately 2 to 3 g of the air

dried crude drug in the tared platinum or silica dish and incinerate at a temperature not

exceeding 450°C until free from carbon, cool and weigh. If a carbon-free ash cannot be

obtained in this way, exhaust the charred mass with hot water, collect the residue on an ash

less filter paper, incinerate the residue and filter paper until the ash is white or nearly so.

Calculate the percentage of ash with reference to the air-dried drug.

oMethod II

Heat a silica or platinum crucible to red heat for 30 minutes; allow cooling in a dessicator

and weighing. Unless otherwise specified in the individual monograph, weigh accurately

about 1g of the substance being examined and evenly distribute it in the crucible. Dry at

100°C to 105°C for 1 hour and ignite to constant weight in a muffle furnace at 600° +

25°C. Allow the crucible to cool in a dessicator after each ignition. The material should not

catch fire at any time during the procedure. If after prolonged ignition a carbon free ash

cannot be obtained, proceed as directed in method I. Ignite to constant weight. Calculate

the percentage of ash with reference to the air-dried substance.

Acid Insoluble Ash

Boil the ash obtained for 5 minutes with 25 ml of dilute hydrochloric acid, collect the

insoluble matter in a Gooch crucible or on an ashless filter paper, wash with hot water and

ignite to constant weight. Calculate the percentage of acid insoluble ash with reference to the

air dried drug.11

Water Soluble Ash

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Boil the ash for 5 minutes with 25 ml of water, collect insoluble matter in a Gooch crucible

or on an ashless filter paper, wash with hot water, and ignite for 15 minutes at a temperature

not exceeding 450°c. Subs tract the weight of the insoluble matter from the weight of the ash,

the difference in weight represents the water soluble ash. Calculate the percentage of water

soluble ash with reference to the air dry.11

Water Soluble Extractive

This method determines the amount of active constituents in a given amount of medicinal

plant material when extracted with solvents. It is employed for that material for which no

chemical or biological assay method exist. As mentioned in different official books (Indian

Pharmacopoeia 1996, British Pharmacopoeia 1980, British Herbal Pharmacopoeia.1990 etc.),

the determination-of water soluble and alcohol soluble extractives, is used as a means of

evaluating crude drugs which are not readily estimated by other means.11

Method I

5 g of the air-dried drug, coarsely powdered have to be macerated with 100 ml of water

closed flask for 24 hours, shaking frequently during the first 6 hours and allowing to stand

for 18 hours. Thereafter, filter rapidly taking precautions against loss of water, evaporate 25

ml of the filtrate to dryness in a tared flat-bottomed shallow dish, dry at 105°C and weigh.

The percentage of water-soluble extractive with reference to the air dried drug has to be

calculated.

oMethod II

Add 5 g of powdered drug to 50 ml of water at 80°C in a stoppered flask. Shake well and

allow to stand for 10 minutes. Cool, add 2 g of kieselguhr and filter. Transfer 5 ml of the

filtrate to a tared evaporating dish 7.5 cm in diameter. Evaporate the solvent on a water bath,

continue drying for 30 minutes, finally dry in a steam oven for 2 hours and weigh the residue.

Calculate the percentage of water-soluble extractive with reference to the air-dried drug.

Alcohol Soluble Extractive

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The alcohol soluble extractive value is also indicative for the same purpose as water soluble

extractive value. The solvent strength of alcohol varies from 20 - 95 % v/v. The solvent

strength has to be chosen depending on the nature of drugs to be extracted. The extractive

value varies depending on the strength of alcohol used for extraction, e.g. ginger when

extracted with 90% alcohol gives an alcohol soluble extractive value of approximately 4.5%

vlv, which-includes the oil and resins present in it. In case of rhubarb, 45% vlv alcohol

strength is suitable to extract the anthraquinone present in it. With reference to Indian

Pharmacopoeia 1996, the ethanol soluble extractive can be determined as follows:

Macerate 5 g of the air dried drug, coarsely powdered, with 100 ml of alcohol of the

specified strength in a closed flask for 24 hours, shaking frequently during six hours and

allowing standing for eighteen hours. Filter rapidly, taking precautions against loss of

solvent, evaporate 25 ml of filtrate to dryness in a tared flat bottomed shallow dish, and dry

at 105°, to constant weight and weigh. Calculate the percentage of alcohol soluble extractive

with reference to the air dried drug.11,25

Water Soluble Extractive

Proceed as directed for the determination of Alcohol soluble extractive, using chloroform

water instead of ethanol.

Ether Soluble Extractive (Fixed Oil Content)

Transfer the suitably weighed quantity of the air dried, crushed drug to an extraction thimble,

extract with solvent ether (or petroleum ether, b.p. 40° to 60°) in a continuous extraction

apparatus (Soxhlet) for 6 hours. Filter the extract quantitatively into a tared evaporating dish

and evaporate off the solvent on a water bath. Dry the residue at 105° to constant weight.

Calculate the percentage of ether soluble extractive with reference to the air dried drug.

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In the determination of all extractive values, the percentage has to be determined with respect

to the air-dried material where the determination of moisture content is important. This is in

contrast to some of the assay procedures on plant drugs, where, if the drug has to be dried

before extraction apparatus is made for the loss on drying and the constituent content is

calculated with reference to the un-dried or fresh drug. 11

Moisture content:

Moisture is an inevitable component of crude drugs, which must be eliminated as far as

practicable. The preparation of crude drug from the harvested drug plants involves cleaning

or garbling to remove soil or other extraneous material followed by drying which plays a

very important role in the quality as well as purity of the material. The objective of drying

fresh material is:

To aid in their preservation

To "fix" their constituents, i.e., to check enzymatic or hydrolytic reactions that might alter

the chemical composition of the drug

To facilitate subsequent comminution (grinding into a powder) and

To reduce their weight and bulk

Insufficient drying favors spoilage by molds and bacteria and makes possible the enzymatic

destruction of active principles. The moisture requirements for the active growth of some of

the common molds and bacteria that may be found in or on drugs are relatively low.

Therefore, the drying process should reduce the moisture content of the drug below this

critical, or threshold level. Since the moisture requirements for enzymatic activity and that

which microorganisms demand, vary not only with the species, but also with other

environmental factors (e.g., temperature, oxygen and carbon dioxide tension, light etc.). It is

difficult to state a precise upper limit of moisture that can be permitted in crude drugs. The

USP and the NF make no commitment in this regard in most cases. However, most drugs

may be stored safely if the moisture content is reduced to 6 per cent or less. A notable

exception is agar, for which USP permits as much as 20 per cent moisture.

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. If the rate is too

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slow, much spoilage may occur before the drying process is completed. Therefore, in

general, drying should be accomplished as rapidly as is possible with good practice. The

duration of the drying process varies from a few hours to several weeks, depending on the

water content and other features of the drugs. Consideration of the time during which an

elevated drying temperature is maintained is important, because destructive enzymatic

reactions are accelerated by increasing the temperature, although the net effect of most such

reactions commonly encountered in the preparation of crude drugs is accelerated only up to

approximately 45°C. But higher temperatures shorten the time required for drying, and thus

the time during which destructive reaction can occur also. The methods employed for drying

are variable in detail, but they may be classified as spontaneous or as artificial. Artificial

methods may be physical, which involves the use of elevated temperature and/or decreased

pressure (vacuum), or the use of radiation of infrared or radio-frequency wave lengths; or

they may be chemical, which involve use of the desiccants.

The extractive values as described under section 9.2 determine the presence of specific

component or group of specific components or contaminants in a plant drug. The moisture

content of many crude drugs may be ascertained by the simple physical process of

evaporation. A weighed sample of the crude herb is dried at 100°C and weighed periodical~

until no more than 0.25 percent is lost in one hour's drying. The total weight lost is expressed

as a percentage of the initial weight of the sample; this figure is the moisture content of the

sample. The residual moisture (if any) which cannot be driven off in this way is called

"bound" water. A high-speed mill or other devices that are likely to create excessive heat I

from friction should not be used for grinding or cutting samples intended for moisture

determination.

It is doubtful whether moisture can truly be classified with these types of constituents an

contaminants, but as the procedure for the determination of moisture is analogous with the

extraction methods described, it is included in this section. Excess moisture in a sample

suggests not only that the purchaser could be paying a high price for unwanted water, but

also that the drug has been incorrectly prepared, or, subsequent to preparation, has been

incorrectly stored. Excess moisture can result in the breakdown of important constituents by

enzymatic activity and may encourage the growth of -yeast and fungi during storage. The

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results in either case will be the eventual rejection of the drug as an unsuitable material.

Moisture content limits are stated in the pharmacopoeial monographs on many drugs. Other

drugs have no limit statement expressed, the limit, by inference, being that the drug should be

air-dried. This only requires that the drug has reached equilibrium with the surrounding

humidity, which will naturally vary according to the location of the material. The

significance of this standard is demonstrated in the exercises on the moisture content of

starch and digitalis.

Methods of determination of moisture content include the loss on drying, the volumetric

azeotropic distillation method and the titrimetric Karl Fischer method. Which method is to

be applied depends on the nature of the drug and its constituents.

The test for loss on drying determines both water and volatile matter in the crude drug. It can

be carried out either by heating at 1 00°C-1 05°C or in a desiccator’s over phosphorous pent

oxide under atmospheric or reduced pressure at room temperature for specific period of time.

The second method is especially useful for those materials that melt to a sticky mass at

elevated temperature.11

Particle size:

For some herbal substances intended for use in herbal teas or solid herbal medicinal products,

particle size can have a significant effect dissolution rates, bioavailability, and/or stability. In

such instances, testing for particle size distribution should be carried out using an appropriate

procedure, and acceptances criteria should be provided. Particle size can also be affected the

disintegration time of solid dosage forms.

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Contaminants:

i) Inorganic impurities /Toxic metals:

The need for inclusion of tests and acceptance criteria for inorganic impurities should be

studied during development and based on knowledge of the plant species, its cultivation and

the manufacturing process.11

ii) Determination of arsenic:

The medicinal plant materials can be contaminated with arsenic and heavy metals which can

be attributed to many causes including environmental pollution and traces of pesticides. As

these components even in trace amounts are dangerous, they have to be removed from the

herbal drugs. Limit tests for these materials have been prescribed in almost all the

Pharmacopoeia through out the world. As prescribed by WHO the following procedures have

been recommended for their respective limit tests 11

Limit Test for Arsenic:

The amount of arsenic in the medicinal plant material is estimated by matching the depth of

color with that of a standard stain. The limit test can be accomplished by using the following

procedures.

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Preparation of the sample by acid digestion:

Place 3S-70 g of coarsely ground material, accurately weighed, in a kjeldahl flask, capacity

800-1000 ml. Add 10-25 ml of water and 25-50 ml of nitric acid (-1000 g/l) and then

carefully add 20 ml of sulfuric acid (-1760g/l), drop by drop, until all the organic matter is

destroyed.

This is achieved when no further darkening of the solution is observed with continued

heating, and a clear solution with copious vapors of sulfur trioxide is obtained. Cool, and add

75 ml of water and 25 ml of ammonium oxalate (25g/l). Heat again until sulfur trioxide

vapors develop. Cool, transfer with the help of water to a 250 ml volumetric flask, and dilute

to volume with water(1).

Apparatus

A suitable type of apparatus is constructed as follows. A wide mouthed bottle of about 120ml

capacity is fitted with a rubber bung through which passes a glass tube. The latter, made from

ordinary glass tubing, has a total length of about 200 mm and an internal diameter 01 exactly

6.5 mm (external diameter about 8 mm). The lower end of -the tube is drawn out to an

internal diameter of about 1 mm, and there is a hole not less than 2 mm in diameter below the

side of the tube, near the constricted part. The tube is positioned so that when the bottle

contains 70 ml of liquid the constricted end is above the surface of the liquid and the hole in

the side is below the bottom of the tube, with slightly rounded-off edges. One of two rubber

bungs (about 25 mm x 25 mm), each with a central hole of exactly 6.5 mm diameter, is fitted

at the upper end of the tube. The other bung is fitted with a piece of glass tube about 3 mm

long and with an internal diameter of exactly 6.5 mm and with a similar ground surface. One

end of each of the tubes is flush with the larger end of the bungs, so that when these ends are

held tightly together with a rubber band or a spring clip, the openings of the two tubes meet

to form a true tube. Alternatively, the two bungs may be replaced by any suitable

construction satisfying the conditions described in the test.11

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Method

Moisten some cotton-wool with lead acetate (80 g/I), allow drying, and lightly packing into

the tube which fits into wide-mouthed bottle to not less than 25 mm from the top. Between

the flat surfaces of the tubes, place a piece of mercuric bromide paper that is large enough to

cover their openings \ -15 mm x 15 mm). The mercuric bromide paper can be fitted byan1

other means provided that:

The whole of the evolved gas passes through the paper

The portion of the paper in contact with the gas is a circle 6.5 mm in diameter The paper is

protected from sunlight during the test

Place an aliquot (25-50 ml) of the solution being tested, prepared as described above, in the

wide-mouthed bottle. Add 1 g of potassium iodide ASR and 10 g of granulated zinc ASR and

place the prepared glass tube assembly quickly in position. Allow the reaction to proceed for

40 minutes. Compare any yellow stain that is in a similar manner with a known quantity of

dilute arsenic As TS. Examine the test and standard stains without delay in daylight; the

stains fade with time.

The most suitable temperature for carrying out the test is generally about 40°C but, as the

rate of evolution of the gas varies somewhat with different batches of granulated zinc ASR,

the temperature may have to be adjusted to obtain an even evaluation of gas. The reaction

may be accelerated by placing the apparatus on a warm surface, care being taken to ensure

that the mercuric bromide paper remains dry throughout. Between successive tests, the tube

must be washed with hydrochloric acid (- 250g/l) As TS, rinsed with water and dried.(1)

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Limit Test for Cadmium and Lead

The method of determination is left to the analyst. Nevertheless the determination must be

consistent and sensitive enough to allow comparison with a reference material. The

procedure for the determination of the same as recommended by the WHO is as follows:11

Apparatus

The equipment consists of a digestion vessel, consisting of a vitreous silica crucible (DIN

12904), "tall form", height 62 mm, diameter 50 mm, capacity 75 ml, with a vitreous silica

cover.

Materials used are:

Digestion mixture: 2 parts by weight of nitric acid (-1 000g/1) TS and 1 part by weight of

perchloric acid (-1170g/I).

Reference materials: olive leaves (Olea europaea) and hay powder.

Clean scrupulously with nitric acid (-1000g/l) the digestion vessel and all other equipment to

be used for the determination, rinse thoroughly several times with water and dry at 120°C.

Preparation of the sample:

For the wet digestion method in an open system, place 200-250 mg of air-dried plant

material, accurately weighed, finally cut and homogeneously mixed, into a cleaned silica

crucible. Add 1 ml of the digestion mixture, cover the crucible without exerting pressure and

place it in an oven with a controlled temperature and time regulator (computer-controlled, if

available). Heat slowly to 1OQoC and maintain at this temperature for up to 3 hours, then

heat to 120°C and maintain at this temperature for 2 hours. Raise the temperature very slowly

to 240°C, avoiding losses due to possible violent reactions especially in the temperature

range of 160-200°C, and maintain at this temperature for 4 hours. Dissolve the remaining dry

inorganic residue in 2.5 ml of nitric acid (-1000g/l) and use for the determination of heavy

metals. Every sample should be tested in parallel with a blank.

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Method

The contents of lead and cadmium may be determined by inverse voltametry or by atomic

absorption spectrophotometry. The following maximum amounts in dried plant materials,

which are based on the ADI values, are proposed:

Lead, 10 mg/kg

Cadmium, 0.3 mg/kg

Microbial limits:

There may be a need to specify the total count of aerobic micro-organisms, the total count of

yeasts and moulds, and the absence of specific objectionable bacteria. The section contains

tests for the determination of the number of replicable microorganisms and for the

demonstration of the absence of certain species of microbes in all types of pharmaceutical

products and minerals, from crude starting materials to finished products. Strict adherence to

aseptic working conditions must be ensured in the preparation and execution of the tests.

Unless stated otherwise, ‘incubation’ means the storage of the material in an incubator at 30-

35 C for 24-48 hours. The word ‘growth’ is used in the sense of expressing the presence and

expected multiplication of live micro - organisms.11

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Limits of Microbial load:

Microbes Plant material for topical

use Per gram

Plant material for internal

use per gram

Aerobic Bacteria 107 105

Yeast and moulds 104 103

Escherichia coli 102 10

Other enterobacteria 104 103

Salmonella None None

Mycotoxins

The potential for mycotoxins contamination should be fully considered. Where necessary

suitable validated methods should be used to control potential mycotoxins and the acceptance

criteria should be justified.

Pesticides, fumigation agents etc

Microbiological contamination and foreign materials are important quality criteria in the

testing of medicinal plants. As with any other product from agricultural or wild sources,

medicinal plants can be contaminated by organic substances of natural or synthetic origin ,

such as insects, micro-organisms, e.g. fungi and their mycotoxins , radioactive materials ,

fumigation residues and plant protection substances, i.e. pesticides.

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Pesticides are simple substances or mixtures used to eliminate undesirable vegetable and

animal life in agricultural and urban ecosystems. Owing to the great variability in plant

chemical composition that results from factors to which plants are exposed during their

growth, storage and the different stages of manipulation, characterization and /or

standardization of phytopharmaceuticals are necessary. Standardization of herbal

preparations should allow the knowledge of their composition and prevent, or at least make

less likely, the consumption of drugs of questionable quality. Depending on the type of

preparation, organoleptic features, moisture and ash content, physical properties and

adulterants are check to confirm identity and determine purity.11

Other appropriate tests:

Swelling Index:

The dried ripe seeds of Plantago ovata, P. psylium, P. arenaria, P. indica etc. contain

mucilage in the epidermis of the testa. The seeds of such types of plant may be evaluated by

measuring the volume of mucilage produced in 24 hours from 1 g of the seeds. This

evaluation procedure is termed as swelling factor. The swelling index is the volume in ml

taken up by the swelling of 1 g of plant material under specified conditions. Its determination

is based on the addition of water or a swelling agent as specified in the test procedure for

each individual plant material (either whole, cut or pulverized). Using a glass-stoppered

measuring cylinder, the material is shaken repeatedly for 1 hour and then allowed to stand for

a required period of time. The volume of the mixture (in ml) is then read. The mixture of

whole plant material with the swelling agent is easy to achieve, but cut or pulverized material

requires vigorous shaking at specified intervals to, ensure even distribution of the material in

the swelling agent. As this constitutes a valid parameter for the evaluation of the

mucilaginous plant, the W!-IO has prescribed the following method for the determination of

the swelling index.11

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Recommended Procedure for the Determination of Swelling Index

No fewer than three determinations for any given material have to be carried out

simultaneously. The specified quantity of the plant material concerned is introduced,

previously reduced to the required fineness and accurately weighed, into a 25 ml glass

stoppered measuring cylinder. The internal diameter of the cylinder should be about 16 mm,

the length of the graduated portion about 125 mm, marked in 0.2 ml divisions from 0 to 25

ml in an upwards direction. Unless otherwise indicated in the test procedure, 25 ml of water

is to be added. The mixture is shaken thoroughly every 10 minutes for 1 hour. Allow to stand

for 3 hours at room temperature or as specified. The volume (in ml) has to be measured

which is occupied by the plant material, including any sticky mucilage. The mean value of

the individual determinations is calculated relating to 1 g of plant material.11

Assay:

In the case of herbal substances with constituents of known therapeutic activity or with active

markers, assays of their content are required with details of the analytical procedures. Where

possible, a specific, stability- indicating procedure should include determining the content of

the herbal substance. In cases where use of non –specific assays justified, other supporting

analytical procedures may be used to achieve overall specificity, if required.

Foaming Index:-

The saponins are high molecular weight containing phytoconstituents having the detergent

activity. Saponins are mostly characterized based on their frothing property. Medicinal plants

of different groups, especially those derived from the families Caryophyllaceae, Araliaceae,

Sapindaceae, Primulaceae, and Dioscoreaceae contain saponins. 11

Recommended procedures for foaming index determination

Reduce about 1gm of the plant material to a coarse powder (sieve no. 1250) , weigh

accurately and transfer to a 500ml conical flask containing 100ml of boiling water. Maintain

at moderate boiling for 30min. Cool and filter into a 100ml volumetric flask and add

sufficient water through the filter to dilute to volume. Pour the decoction in to ten stoppered

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test tubes (height 16cm , diameter 16mm) in successive portion in 1ml ,2ml, 3ml and adjust

the volume of the liquid in each tube with water to 10ml. Stopper the tubes and shake them

in a length wise motion for 15sec, two shakes per second. Allow to stand for 15min and

measure the height of the foam.

Calculate the foaming index by using the following formula: -

1000 / A

Where, A= the volume in ml of the decoction used for pre paring the dilution in the tube

where foaming to a height of 1cms is observed.

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Herbal preparationsThey are obtained by subjecting herbal substances to treatments such as extraction,

distillation, expression, fractionation, purification, concentration or fermentation. These

include comminuted or powdered herbal substances, tinctures, extracts, essential oils,

expressed juices and processed excudes.

Identification tests:

o Water content

o Residual Solvents

o Inorganic impurities, toxic metals

o Microbial Limits

o Mycotoxins

o Pesticides, Fumigation agents,etc

o Assay

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Herbal medicinal products

These are any medicinal product, exclusively containing as active substances one or more

herbal substances or one or more herbal preparation, or one or more herbal substances in

combination with one or more such herbal preparations.

The tests and acceptance should be included for particular herbal medicinal products. The

specific dosage forms addressed include solid oral herbal medicinal products.

Tablet (Coated and uncoated) and hard capsules:

One or more of these tests may also be applicable to soft capsule and granules.

a) Disintegration :

The first important step toward solution is break down of the tablet into smaller particles, a

process known as disintegration.

Disintegration Test For Tablets

Apparatus

(a) A rigid basket – rack assembly supporting six cylindrical glass tubes, 77.5+ -2.5 mm

long, 21.5mm in internal diameter and with a wall thickness of about 2mm.

(b) The tubes are held vertically by two superimposed transparent plastic plates, 90mm in

diameter and 6m thick, perforated by six holes having the same diameters as the

tubes. The holes are equidistant from the centre of the plate and are equally spaced

from one another. Attached to the under side of the lower plate is a piece of woven

gauze made from stainless steel wire 635micro meter in diameter and having nominal

mesh apertures of 2.00mm The upper plate is covered with a stainless steel disc

perforated by six holes, each about 22mm in diameter, which fits over the tubes and

holds them between the plastic plates. The holes coincide with those of the upper

plastic plate and the upper open ends of the glass tubes.

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(c) The plates are held rigidly in position and 7705mm apart by vertical metal rods at the

periphery and a metal enable the assembly to be attached to a mechanical device

capable of raising and lowering it smoothly at a constant frequency of between 28

&32 cycles per minute through a distance of 50&60 mm.

(d) A cylindrical disc for each tube, each 20.7+- o.15mm in diameter & 9.5+-0.15mm

thick, made of transparent plastic with relative density of 1.18 to 1.20, & pierced with

5holes, each of 2mm in diameter, 1 in the centre & the other 4 spaced equally on the

circle of radius 6mm from the centre of the disc.

(e) The assembly is suspended in the liquid medium in a suitable vessel, preferably a

1000ml beaker.

(f) A thermostatic arrangement for heating the liquid & maintaining the temperature at

37o +-2o.

Method

Unless otherwise stated in the individual monograph, introduced 1tab into each

tube, add a disc to each tube. Suspend the assembly in the beaker containing the

specified liquid and operate the apparatus for the specified time. Remove the

assembly from the liquid. The tablet pass the test if all of them are disintegrated.

If 1or2 tab. failed to disintegrate repeat the test on 12 additional tab; not less

than 16 of the total of 18 tab. Tested disintegrate

b) Dissolution:

The original rationale for using tablet disintegration tests was the fact that as the tablet breaks

down into smaller particles, it offers a greater surface area to the dissolving media and

therefore must be related to the availability of the drug to the body.

Dissolution Test For Tablets

Apparatus 1

An assembly consisting of the following:

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(a) A cylindrical vessel, A, made of borosilicate glass or any other suitable transparent

material, with a hemispherical bottom and with a nominal capacity of 1000 ml . The

vessel has a flanged upper rim and is fitted with a lid that has a number of openings,

one of which is central.

(b) A motor with a speed regulator capable of maintaining the speed of rotation of the

paddle with in 4% of that specified in the individual monograph. The motor is fitted

with a stirring element which consists of a drive shaft and blade forming a paddle, B

(c) A water-bath set to maintain the dissolution medium at 36.5o to 37.5o . The bath liquid

is kept in constant and smooth motion during the test. The vessel is securely clamped

in the water-Bath in such a way that the displacement vibration from other

equipment.

Method :-

Introduce the stated volume of the dissolution medium, free from dissolved air, in to the

vessel of the apparatus. Warm the dissolution medium to between 36.5o and 37.5o.Unless

otherwise stated use one tablet . When Apparatus 1 is used, allow the tablet to sink to the

bottom of the vessel prior to the rotation of the paddle. A suitable device such as a wire

or glass helix may be used to keep horizontal at the bottom of the vessel tablets that

would otherwise float. Care should be taken to ensure that air bubbles are excluded from

the surface of the tablet . Perform the analysis as directed in the individual monograph.

Repeat the whole operation five times. Where two or more tablets are directed to be

placed together in the apparatus, carry out six replicate tests.

For each of the tablet tested, calculate the amount of dissolved active ingredient in the

solution as a percentage of the stated amount.

c) Hardness:

Tablets require a certain amount of strength, or hardness and resistance to friability, to

withstand mechanical shocks of handling in manufacture, packaging, and shipping.

Historically, the strength of a tablet was determined by breaking it between the second and

third fingers with the thumb acting as a fulcrum. If there was a sharp snap, the tablet was

deemed to have acceptable strength. Nowadays diametric compression tests are applied by

using following instruments:14

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Monsanto tester,

Strong-Cobb tester,

Pfizer tester,

Erweka tester etc.

The Monsanto hardness tester consists of a barrel containing a compressible spring held

between two plungers. The lower plunger is placed in contact with the tablet, and a zero

reading is taken. The upper plunger is then forced against a spring by turning a treaded bolt

until the tablet fractures. The force of fracture is recorded, and the zero force reading is

deducted from it.

The Strong –Cobb tester was developed about 20 years later. The original design employed a

plunger activated by pumping a lever arm, which forces an anvil against a stationary platform

by hydraulic pressure. The force required to fracture the tablet is read from a hydraulic

gauge.

The Pfizer tester was developed and made available to the industry. This tester operates on

the same mechanical principle as a pair of pliers. As the plier’s handles are squeezed, the

tablet is compressed between a holding anvil and a piston connected to a direct force reading

gauge. 14

d) Friability:

The tablet friability can be determined by Roche friabilator. The tablets are subjected to the

combined effects of abrasion and shock by utilizing a plastic chamber that revolves at 25

rpm, dropping the tablets at a distance of 6 inches with each revolution. Normally, a

preweighed tablet sample is placed in the friabilator, which is then operated for 100

revolutions. The tablets are then dusted and reweighed. Loss of tablet material less than 0.5

to 1.0% of the tablet weight is accepted.14

e) Weight Variation:

As per USP weight variation test, 20 tablets are weighed individually; average weight is

calculated, followed by comparing the individual tablet weights to the average. The tablets

meet the USP test if not more than 2 tablets are outside the percentage limit and if no tablet

differs by more than 2 times the percentage limit.14

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Table: Weight variation tolerances for uncoated tablets:

S.No. Average weight of tablets(mg) Max. % difference allowed

1.

2.

3.

130 or less

130- 324

More than 324

10

7.5

5

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f) Moisture content:

Moisture is an inevitable component of crude drugs, which must be eliminated as far as

practicable. The preparation of crude drug from the harvested drug plants involves cleaning

or garbling to remove soil or other extraneous material followed by drying which plays a

very important role in the quality as well as purity of the material. The objective of drying

freshmaterial is: 11

To aid in their preservation

To "fix" their constituents, i.e., to check enzymatic or hydrolytic reactions that

might alter the chemical composition of the drug

To facilitate subsequent comminution (grinding into a powder) and

To reduce their weight and bulk

g) Uniformity of dosage units:

This term include both uniformity of content and uniformity of mass.

h) Microbial limits

Microbial limit testing is seen as an attribute of good manufacturing practice, as well as of

quality assurance. It is advisable to test the herbal product unless its components are tested

before manufacture and the manufacturing process is known, through validation studies, not

to carry a significant risk of microbial contamination.

Where appropriate, acceptance criteria should be set for the total count of aerobic micro-

organisms, the total count of yeasts and moulds, and the absence of specific objectionable

bacteria (e.g., Staphylococcus aureus, Escherichia coli, Salmonella, pseudomonas).Counts

should be determined using phamacopoeial or other validated procedures, and a sampling

frequency or time point in manufacture which is justified by data and experience. With

acceptable scientific justification, it may be possible to omit microbial limit testing for solid

dosage forms.11

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Oral liquids:

One or more of the following specific test will normally be applicable to oral liquids and to

powders intended for reconstitution as oral liquids.22

i) Uniformity of dosage units:

This term include both uniformity of content and uniformity of mass. Generally, acceptance

criteria should be set for weight variation, fill volume, and/or uniformity of fill.

Pharmacopoeial procedures should be used

If appropriate, tests may be performed as in-process controls; however, the acceptance

criteria should be included in the specification. This concept may be applied to both single-

dose and multiple dose packages.

The dosage unit is considered to be the typical dose taken by the patient. If the actual unit as

taken by patient, is controlled, it may either be measured directly or calculated, based on the

total measured weight or volume of drug, divided by the total number of doses expected. If

dispensing equipment (such as medicine droppers or droppers tips for bottles) is an integral

part of packaging, this equipment should be used to measure the dose. Otherwise, a standard

volume measure should be used. The dispensing equipment to be used is normally

determined during development.

For powders for reconstitution, uniformity of mass testing is generally considered

acceptable.11,14

ii) pH:

Acceptance criteria for pH should be provided where applicable and the proposed range

justified.

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iii) Microbial limits:

Microbial limit testing is seen as an attribute of good manufacturing practice, as well as of

quality assurance. It is advisable to test the herbal product unless its components are tested

before manufacture and the manufacturing process is known, through validation studies, not

to carry a significant risk of microbial contamination.

Where appropriate, acceptance criteria should be set for the total count of aerobic micro-

organisms, the total count of yeasts and moulds, and the absence of specific objectionable

bacteria (e.g., Staphylococcus aureus, Escherichia coli, Salmonella, pseudomonas).Counts

should be determined using phamacopoeial or other validated procedures, and a sampling

frequency or time point in manufacture which is justified by data and experience. With

acceptable scientific justification, it may be possible to omit microbial limit testing for solid

dosage forms.

iv) Antimicrobial Preservative Content:

For oral liquids needing an antimicrobial preservative, acceptance criteria for preservative

content must be stated. These criteria should be based on the levels necessary to maintain

microbiological product quality throughout the shelf-life.

Releasing testing for antimicrobial preservative content should normally performed. Under

certain circumstances, in-process testing may suffice in lieu of release testing. When

acceptance criteria hen antimicrobial preservative content testing is performed as an in-

process test, the acceptance criteria should remain part of the specification.

Antimicrobial preservative effectiveness should be demonstrated during development, during

scale-up, and through shelf-life.23,24

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v) Antioxidant preservative content:

Releasing testing for antioxidant content should normally performed. Under certain

circumstances, where justified by development and stability data, shelf –life testing may be

unnecessary, and in-process testing may suffice in lieu of release testing. When accept

antioxidant content testing is performed as an in-process test, the acceptance criteria should

remain part of the specification. If only release testing is performed, this decision should be

reinvestigated whenever either the manufacturing procedure or the container/closure system

changes.

vi) Extractables:

Generally, where development and stability data show no significant evidence of extractable

from the container/closure, elimination of this test may be proposed. This should be

reinvestigated if the container/closure system changes.

Where data demonstrate the need , tests and acceptance criteria for extractable from the

container-closure system components ( e.g. , rubber stopper , cap liner , plastic bottles, etc.)

are considered appropriate for oral solutions packaged in non-glass system, or in glass

containers with non-glass closure. The container/closure components should be listed, and

data collected for these components as early in the development process as possible. 23,24

vii) Alcohol content:

Where it is declared quantitatively on the label in accordance with pertinent regulations, the

alcohol content should be specified11

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.

viii) Dissolution:

In addition to the attributes recommended immediately above it may be appropriate (e.g.

where constituents of the herbal substance or herbal preparation are sparingly soluble) to

include dissolution testing and acceptance criteria for oral suspensions and dry powder

products for resuspension.

Dissolution testing may be performed as in-process test, or as a release test, depending on its

relevance to product performance. The discussion of dissolution for solid dosage forms, and

of particle size distribution, should also be considered.14

ix) Particle Size Distribution:

Quantitative acceptance criteria and a procedure fort determination of particle Size

Distribution may be appropriate for oral suspensions

Particle size distribution testing may be performed as in-process test, or as a release test,

depending on its relevance to product performance. If these products have been demonstrated

during development to have consistently rapid drug release characteristics, exclusion of a

particle size distribution test from the specification may be proposed.

Particle size distribution testing may also be proposed in place of dissolution testing;

justification should be provided. The acceptance criteria should include acceptable Particle

size distribution in terms of the percentage of total particle size ranges. The mean, upper,

and/or lower particle size limits should be well defined.14

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x) Redispersibility:

For oral suspensions, which settle on storage (produce sediment) acceptance criteria for

redispersibility may be appropriate. Shaking may be an appropriate test. The procedure

(mechanical or manual) should be indicated. Time required to achieve resuspension by the

indicated procedures should be clearly defined. Data generated during product development

may be sufficient to justify skip lot testing, or elimination of this attribute from the

specification.14

xi) Rheological Properties:

For relatively viscous solutions or suspensions, it may be appropriate to include rheological

Properties (viscosity) in the specification. The test and acceptance criteria should be stated.

Data generated during product development may be sufficient to justify skip lot testing, or

elimination of this attribute from the specification.14

xii) Specific Gravity:

The specific gravity of a liquid is the weight of a given volume of the liquid at 25°

Compared with the weight of an equal volume of water at the same temperature, all

Weighing being taken in the air.11

Method:

Proceed as described under Wt. per ml. Obtain the specific gravity of the liquid by

Dividing the weight of the liquid contained in the pyknometer by the weight of the water

Contained, both determined at 25° unless otherwise directed in the individual

Monograph.(1)

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Xiii) Reconstitution Time:

Acceptance criteria for reconstitution Time be provided for dry powder products, which

require reconstitution. The choice of diluents should be justified. Data generated during

product development may be sufficient to justify skip lot testing, or elimination of this

attribute from the specification.

xiii) Water Content:

For oral products requiring reconstitution, a test and acceptance criterion for water content

should be proposed when an appropriate. Loss on drying is generally considered sufficient if

the effect of absorbed moisture vs. water of hydration has been adequately characterized

during the development of the product. In certain cases (e.g. essential-oil containing

preparations) a more specific procedure (e.g., Karl Fischer titration) is required.11

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PHYSICAL QUALITY ASSURANCE

Quality assurance of phyto-pharmceuticals products has so far been discussed solely from the

chemical and physiological point of view. The physical quality however plays an equally

important role for the manufacturer and processor of plant extracts. Without the addition of

suitable adjuvant substances, many plant extracts occur in a form, which makes further

processing considerably more difficult, often even impossible. Hence , extracts of Crataegus

fruits, Curcuma extracts and many others cannot be processed to more manageable dry

products either by roller, belt or spray drying. One particular example is the male fern

extract, which is produced as a solvent free thin extract. In all such cases the manufacturer

cannot handle this without consideration addition adjuvant substances (Newall, 1996) .

Before drying therefore, a proportion of Aerosil, lactose, maltodextrin, glucose syrup or

starch constituting up to 50% of the end product is added to such plant extracts. As the ratio

of active substances to accompanying plant substances remain unaltered here, the

manufacturer has only to declare the measures he has taken.11

Quality Assurance by Cultivation and Breeding

Although medicinal plant cultivation and breeding are not in the province of pharmaceuticals

technology, but they may have great influence on the use of phyto -pharmaceuticals as useful

medicines.GAP has a major role to play in QA based on the following parameters.

The fact that that many medicinal substances of natural origin cannot be synthesized

Only with unacceptably great effort, necessitates creation of the natural starting

material i.e., cultivation of the medicinal plant.

The unreliability of supply of drug plants gathered from the wild shows the need for their

cultivation. The qualities available in the often widely scattered gathering areas are limited.

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Expert collectors are becoming increasingly difficult to find. All this results in the increasing

occurrence of mistaken identity and adulteration of drug plant materials.

The increased demands for safety of medicines in general have also led to increasing

demands for the purity and quality of phytopharmaceuticals and of the plant drug materials

from which they are gathered.

Legal regulations such as the 1973 Washington protection of species agreement and the

more recent 1980West German nature protection order will considerably hinder the trade and

processing of wild plants.11

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Medicinal plants must be cultivated with phytochemical aspects in view, as the success of

such cultivation depends less on the quality of plants produced and much more on their

quality. The active substance content of a cultivated medicinal plant can be affected by

various factors:

Genetic variation and hereditary transmission of the secondary substances

Morpho and ontogenic variability, i.e. differences in the active substances contents in

various parts of the plant and during its growth.

Environmental influences 21:

- Temperature

- Rainfall

- Day-length and radiation characteristics

- Altitude

- Atmospheric composition

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SUMMARY

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. SUMMARY

The present work is an attempt to brief out the various quality assurances of herbal

formulation and their parameters. The quality assurance parameters have been briefly

accounted which are to be strictly followed for the herbal formulations, during and after the

manufacturing process, for the finished products in according to ensure their efficacy,

stability and safety till the shelf life of the products. A description regarding the introduction

and history of herbal formulation usage is presented followed by the difference between

quality assurance and quality control and general concept of quality assurance of herbal

formulations like macroscopic and microscopic characterization. The identification tests for

various herbal substances, herbal preparations and herbal medicinal products are also

described and in brief about physical quality assurance and quality assurance by cultivation

and breeding.

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CONCLUSION

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CONCLUSION

Quality assurance of herbal products may be assured by proper control of the herbal

ingredients and by means of GMP. Quality Assurance makes sure you are doing the right

things, the right way. Quality Assurance is a process oriented.. It encompasses the control

and documentation mechanism, which insure, that the multitude of regulations pertaining to

and used in practice of the pharmaceutical industry.

one can not rely upon the quality and efficacy because almost all of the formulations

do not pass through appropriate quality control procedure. The main reason behind this is the

unavailability of systematic quality control procedures for herbal formulations.

Therefore, the pharmaceutical formulations with combinations of drugs have shown

an increasing trend to counteract other symptoms specific to one drug n formulation, and

hence analytical chemist will have to accept the challenge of developing reliable methods for

analysis of drugs in such formulation.

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REFRENCES

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11) Dr. Mukherjee k. pulok, “Quality Control Of Herbal Drugs”, first edition 2002,

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22) Monomancy T. Labels’ potency claim often inaccurate, analysis finds, Los Angeles

Times 1998 August31;A10

23) Herbal Roulette, consumer Reports 1995;60 (Nov):698-705

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29) John H. Book, Organic Medicinal and Pharmaceutical Chemistry, 11 thEdition, 901

(2004).

30) Chaudhri N.C, Gurbani N.K., “Pharmaceutical Chemistry”, 1st Edition, Vallabh

Prakashan, page no. 187-188(1995).

31) Goyal R.K., “Quality Control of herbal and herbal mineral products”, An emerging

Trend, Pharma Times 37.

32) Harnischfeger G., “Quality Assurance of herbal preparations and herbal medicinal

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33) Huxtable Rj. The harmful potential of herbal and other plant products. Drug Safety

1990;5 (suppl 1):126-136

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Declaration

We hereby declare that the work presented below entitled “Market

Survey Of Antihypertensive Drugs” is full of truth in my knowledge

and belief. We are kinely abide by the rules and regulation of our

institute and university. There is no parallel work is going on this

topic in our institute.

Amit D.Khanvilkar

Aman Preet Duggal

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