Ch 1 Pharma Cog Nosy Intro

Chapter No. 1 - General IntroductionSem. 1, Second Professional

By

Abdul Aleem AwanLecturer ,

Pharmacy Department Hazara University.

Pharmacognosy

Pharmacognosy is a branch of pharmacy which deals withthe basic resources of medicines from nature (plant &animal) and their uses as medicaments from ancient timeto present day.

• Pharmacognosy is derived from two Greek words,Pharmakon & Gnosis

• Pharmakon – means ‘drug’.• Gnosis – means ‘knowledge’.• In brief, Pharmacognosy means ‘knowledge of drugs’. It is a study of drugs that originate in the plant & animal

kingdoms.

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• At present pharmacognosy involves not only the crudedrugs but also their natural derivatives (pure compoundsor constituents).

• Digitalis leaf and its isolated glycoside, digitoxin; Rauwolfiaroot and its purified alkaloid, reserpine; and thyroid glandwith its extracted hormone, thyroxine, are all part of thesubject matter of pharmacognosy.

PharmacognosyPharmacognosy may be defined as an important branchof Pharmacy which deals with the study of structural,physical, chemical, biochemical and sensory characters ofnatural drugs of plant and animal origin. It also includesa study of their history, distribution, cultivation,collection, identification, preparation, evaluation,preservation, use and commerce.

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Pharmacognosy - History

• The first or beginning of pre-history on use ofmedicinal plants or herbs or animals, and the placewhere and how used were not well known, and thoseinformation were unwritten for a long time. As aresult, the pre-history on herbs was almost lost.

• However, some information was recorded by oraltransmission from generation to generation.

Pre-history:

History of pharmacognosy is actually the history ofmedicine that is medicinal plants.

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• The written history has originated which was based onregion, religion and culture etc.

The written history was divided into the following:

1. The western medicine2. The Unani (Islam)3. The Ayurveda (Indian)4. The orient5. The Greek History6. The African System

Written History:

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This is originated in Mesopotamia and Egypt. Mesopotamia isconsidered as the first origin of human civilization. TheSumerians (peoples of ancient Mesopotamia) developedcuneiform tablet of herbal medicines. Those tablets arepreserved in British museum.

In Egypt, information had been written on paper – Papyrusebers (1600BC). It consisted of 800 prescriptions, mentioning700 drugs.

The first pharmacopoeia named London Pharmacopoeia waspublished in 1618 and then British Pharmacopoeia waspublished in 1864.

1. The western medicine:

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• This herbal system was developed by Arabian MuslimIbn Sina (980 – 1037 AD). He was a prince and ruler.He was a very brilliant pharmacist and physician whowrote a book – “Kitab-Al-Shifa”, means ‘Book ofHealing’.

• The book was written on Arabic language. This is agreat contribution of Ibn Sina towards medical andpharmaceutical sciences.


2. The Unani (Islam)

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Ayurveda is the term for traditional medicine of ancientIndia.The word “Ayur” means ‘Life’ and “veda” means ‘Thestudy of’ that is “Study of Life”.

The Ayurvedic writings were divided into three systems:

1) Charaka Samhita, 2) Sushruta Samhita and 3)Astanga samhita.

The oldest writing was Charaka Samhita (six to sevencentury before Christ).The book describes uses of many metallic drugs eg.,iron, mercury, sulphur, copper etc with herbs.

Pharmacognosy - History3. The Ayurveda (Indian, 2500-600 BC):

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This is originated from Chinese, Japanese andTibetians etc. The orient herbalism was very old(142 – 220 BC) and called “Kampo”. The writtendocuments were made by the King ‘Shen Nung’(2700 BC) and Shang (1766 – 1122 BC) etc.

Shen Nung investigated medicinal value of severalherbs and written a book – “Pen T-Sao” or nativeherbal.


4. The orient (2700 BC):

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Hippocrates (Father of Medicine, 460-370 BC):

He was the first natural doctor who utilized simple remedies such asvinegar, honey, herbs etc in healing. He is also known to have collectedand identified a number of medicinal plants.

Aristotle (384-322 BC):

He gave the philosophy of medicine. He listed more than 500 plants ofmedicinal importance.

Theophrastus (371-287 BC):

gave scientific basis of use of plants as medicine.

Galen (131-200 AD):

a Greek pharmacist-physician. He developed the methods of preparingand compounding medicines by mechanical means. He was theoriginator of the formulae for a cold cream.

Pharmacognosy - History5. The Greek History:Some of the early naturalists, scientists and physicians who contributed enormously to the development of human knowledge about medicinal plants include following:

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They keep information in their groups or tribes.The information transmitted from one generationto another.

These regions are richest sources of medicinalplants and needs to explore for new drugdiscovery.


6. The African System (Tropical Africa, North and South America):

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Scope of Pharmacognosy

1. Primary source of medicines (from ancient time topresent day), for example – hyoscine, morphine,ergotamine, ouabain etc.

2. Providing Template/guide for the discovery of newdrugs, for example – Pathidine (analgesic drug)designed from morphine.

Pharmacognosy deals primarily with information onthe sources and constituents of natural drugs.

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Terms & Phrase used in

Pharmacognosy

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Standard dictionaries define drug as “an original, simplemedicinal substance, organic or inorganic, used by itselfor as an ingredient in medicine”.

According to WHO’s definition – “any substance used ina pharmaceutical product that is intended to modify orexplore physiological systems or pathological states forthe benefit of the recipient”.

DrugTerminology

Pharmaceutical product/Medicine means “a dosage form(tablet/capsule/syrup/Inj - IV/IM) containing one or moredrugs along with other substances included during themanufacturing process”. 14

Application of Drug

• Prevention of a disease : for example, vaccine.

• Fight against an infection: for example, antibiotics.

• Temporary blocking of a normal function: for example,general & local anesthetics

• Detoxification of the body: for example, antidotes.

• Diagnostic agents: for example, radioisotopes.

• Correction of dysfunction: for example, cardiotonics (eg,digoxin) for the treatment of congestive heart failure.

• Correction of hyperfuntion: for example, Rauwolfia root(eg., reserpine) for the treatment of hypertension.

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Crude Drug:

The term “Crude”, as used in relation to natural products.A crude drug is a natural drug of plant or animal originwhich has undergone no treatment other than collectionand drying, that is, the quality or appearance of the drughas not been advanced in value or improved in conditionby any physical or chemical treatment.

For example: Digitalis leaf, Rauwolfia root etc.

Terminology

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Indigenous vs Naturalized

Indigenous :

Plants growing in their native countries are said to be indigenous tothose regions.

For example: Aconite (Aconitum napellus) in the mountainous regionof Europe. It is highly poisonous used as diuretic in Homeopathypreparation

Terminology

Naturalized:

Plants are said to be naturalized when they grow in a foreign land orin a locality other than their native homes.

For example: Datura (Datura stramonium) which was introduced intothe USA from Europe.

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Official BooksIt provides guideline for the manufacturing, quality control,packaging, storage, dose regimen, indication, contraindication etcof different pharmaceutical products/medicine for the treatmentof diseases.

• USP – United States Pharmacopoeia• BP – British Pharmacopoeia• NF – National Formulary• BNF – British National Formulary• BDNF – Bangladesh National Formulary• BPC – British Pharmaceutical Codex• Martin Dale Extra Pharmacopoeia• Materia Medica• Physician’s Index• Goodman’s & Gilmann’s: The Pharmacological Basis of

Therapeutics. 18

Official vs Unofficial vs Nonofficial drugOfficial drug:

Any drug (crude or prepared) which is included inpharmacopoea or in national formulary or in recognized booksis called an ‘official drug’.For example: quinine, morphine, codeine, paracetamol areincluded in BP, USP, NF and so on.

Terminology

Unofficial drug:A drug which has been recognized earlier in the pharmacopoeiaor in national formulary or in recognized books but not foundin the current issue is designated as an ‘unofficial drug’. Thosesubstances were excluded from the recognized books due totheir severe toxic effects on humans. For example: Sucralfate(hyperacidity), mercurial compounds (diuretics), benzoic acid(preservative) etc. 19

Official vs Unofficial vs Nonofficial drug

Nonofficial drug

Substance that has never been appeared in either ofthe official books may be called nonoffical. Suchtypes of compounds may be published in currentjournals having proven clinical value, but we do notknow about their side effects.

For example - Curcumine (sinusitis), etc.

Terminology

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Terminology

ExtractiveThe crude mixtures of chemical constituents that are removedfrom plants or animals by various extraction processes arecalled extractives or derivatives.

Secondary metabolitesThese are substances synthesized or produced as by-productsby plants during their metabolic activities. Apparently theyare of no primary use to plants.

They are therefore also regarded as ‘waste products ofmetabolism, which are usually accumulated in some parts ofthe plant and are physiologically active on living organisms.

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Monograph

The descriptive material pertaining to any drug,therapeutic agent included in the pharmacopoeia isknown as the monograph.

The monograph of a drug includes the followinginformation on the drug:

official title, synonyms, definition, description,collection or preparation, identity tests, tests foradulterants, method of assay, storage, uses and doses.

Terminology

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Monograph ofTrigonella foenum-graecum (Family: Papilionacacae)

Common name: Fenugreek (Eng.), Methi (Bengali)Cultivation: It is cultivated in different area of Bangladesh, India, Pakistan, MiddleEast, Africa.Description: The Latin species name foenum-graecum means ‘Greek hay’, whichis a dried plant's (leaves or seeds) and has a strong hay-like scent. It has astrong, pleasant and a peculiar odor and grows best in well-drained soils witha low rainfall into brownish- yellow rhombic shape seeds.Parts used: Ripe, dried seedsChemical constituents: Seeds are rich in mucilage (maily galactomannans),fixed oil, fatty acids and protein. They also contain alkaloids, saponine,glycosides etc.Uses: Seeds are diuretics, astringent. They are popularly used in the treatmentof loss of appetite, weight loss, menstrual disorder. Also used inhypertension, diabetes, etc. It lowers TG, cholesterol, LDL.Dose: Daily dose, 18 g. 23

Fenugreek (Kasuri Methi)

Fenugreek seeds Fenugreek with flowers

Dried Fenugreek Fenugreek Powder

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Pharmacognosy & Modern Medicine Simultaneous advancement in the field of

chemistry, biochemistry, biosynthesis andpharmacology has developed pharmacognosy.

Various active compounds have been isolated fromplants which are used in modern medicine.

With the advancement of synthetic organicchemistry most of the active constituents of plantshave been synthesized.

100s of plants are used in modern medicine invarious parts of the world. 25

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Pharmacognosy & Modern Medicine

Important active constituents of plants used in medicine

Active constituents Plants Pharmacological activity

Morphine, Codeine, Papaverine

Papaver somniferum L. Sedative, smooth muscle relaxant

Quinine, Quinidine Cinchona sp. Antimalarial, antiarrthythmic

Hyoscine, Atropine Datura sp., Parasympatholytic

Digitoxin, Digoxin Digitalis lanata Cardiotonic

Reserpine, Rescinamine Rauwolfia sp. Hypotensive, vasodialator

Vincristine, Vinblastin Catharanthus roseus Anticancer

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Caffeine Camellia sinenssis CNS stimulant

Cocaine Erythroxylum coca Anaesthetic

Ephedrine Ephedra sp. Sympathomimetic

Pilocarpine Pilocarpus jaborandi Parasympathomimetic

Ergometrine

Ergotamine

Ergotoxine

Claviceps purpurea Oxytocic

Vasoconstrictor

Vasodialator

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Psyllium mucilage Plantago ovata Laxative

Sennosides Cassia angustifolia

Laxative

Theophylline Caffea arabica CNS stimulantDiuretic

Steroid hormones Solanum sp. Anti-inflammatory, antiarthriytic

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• Plants always provide novel molecular structure,which played important role for the molecular designand development of novel potent, less toxic ornontoxic drugs e.g. natural morphine has gotanalgesic & narcotic effect but meperidine a syntheticdrug originates from morphine basic skeleton is non-narcotic.

• Plant & animal products give potential biologicaleffect without any undesirable effects.

• Plant & animal products can be taken with very ease.

Application of Pharmacognosy

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Drugs obtained from natural sources have a variety oflimitations. The majors are;

• A natural compound may be highly active but usually this isassociated with high toxicity problem, ex- the toxic andtherapeutic dose of digitalis are very close which createserious problem to use this medicine by the patient alone.

• Some compounds are found in nature that give beneficialpharmacological actions but their potencies are too low to beemployed therapeutically.

• The yield of active natural products may be very low andthus the production cost of those drugs will be very high

• The source of a natural drug may be very limited withrespect to geography, season and climate etc.

Limitation of Pharmacognosy

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• At present the prime source of modern or allopathicmedicines is synthesis in the laboratory by organic chemist.

• Only a few of compounds are isolated from plants, whichcannot be replaced by synthetic method.

• For example: morphine isolated from Papaver somniferum;vincristin & vinblastin (anticancer drug) from Vinca rosea,the most potent anticancer drug taxol from Texusbrevifolia;the constituents of digitalis cannot be properly replaced byany synthetic drug like quinidine which is used for thetreatment of arrhythmia.

Sources of Medicaments

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In pharmacognosy, drugs may be classified according to -

1. Their morphology2. The taxonomy of the plants and animals from

which they are obtained3. Their therapeutic/ pharmacological application4. Their chemical constituents or active principles.

Each of these methods of classification hasadvantages and disadvantages.

Classification of Drugs

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• In this system, the drugs are grouped according to the part of theplants, such as roots, leaves, stems, barks, flowers, seeds etc.

• The drugs obtained from the direct parts of the plants are called asorganized drugs. They are made up of whole plants or any partsderived from them.

eg., Root – Rauwolfia, aconite, ginger; Bark – Cinnamon, CinchonaFruit – Amla, Bahera, Capsicum, Leaf – Digitalis, Senna, Tulsi, coca;Wood – Sandal wood.

• The drugs which are prepared from plants by some intermediatephysical process such as incision, drying or extraction with a solventare called unorganized drugs, eg., Dried juice (Aloe juice), Driedextract (agar), Dried latex (Opium latex), Honey, Beewax etc.

Classification of Drugs1. Morphological classification

The main drawback of morphological classification is that there is no co-relation of chemical constituents with the therapeutic actions. 33

• In this system crude drugs are arranged according to thenatural groups (e.g. Families) of their source.

• For example: all the drugs obtained from Solanaceae aregrouped together as Solanaceous drugs.

• Tropane alkaloids are the main constituents ofSolanaceous drugs.


2. Taxonomical classification

Family Drugs

Solanaceae Solanaceous drugs.eg. Tropane alkaloids

Umbelliferae Umbelliferous drugs. eg., volatile oils 34

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• In pharmacological classification the drugs are groupedaccording to their therapeutic use.

• For example cardiotonic drug include digitalis, purgativedrugs include castrol oil.

Classification of Drugs3. Pharmacological classification

Pharmacological action DrugsAnticancer VincaAnalgesic Opium, cannabisPurgatives Senna, Aloe, Castrol oil, Plantago

huskCardiotonic Digitalis, strophanthus

Tranquillizer Rauwolfia rootAnti-inflammatory Tumeric, colchicum

The main drawback of this classification is that a drug can be placed invarious classes according to its therapeutic use. For example: Cinchona(quinine) can be grouped in antimalarial and antiarrhythmic catagories. 35

• The biological activity of a drug is due to thepresence of certain chemical constituents in thedrug.

• Plants and animals synthesize chemicalcompounds such as carbohydrates, protein, fat,volatile oils, alkaloids, resin etc.

• The chemical classification of drugs is dependentupon the grouping of drugs with identicalchemical constituents.


4. Chemical classification

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Classification of DrugsChemical classification of drugs

Chemical constituents Drugs

1. Carbohydratesa) Monosaccharidaseb) Disaccharidec) Polysaccharide

GumMucilagesCellulose

- Dextrose, fructose, galactose- Sucrose, Lactose, Maltose- Starch- Acacia, Tragacanth- Plantago seed- Cotton

2. Glycosidesa) Cardiacb) Anthraquinonec) Saponinsd) Cyanophore

- Digitalis, strophanthus- Aloe, Cascara, senna- Arjuna- Wild cherry bark

3. Tanins Amla, Bohera, Ashoka bark

4. Volatile oil Clove oil, rose oil, peppermint oil, tulsi etc

5. Lipidsa) Fixed oils & fatsb) Waxes

- Olive oil, castor oil, coconut oil etc- Bees wax

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Chemical classification of drugsChemical constituents Drugs

6. Resins ginger, capsicum etc.

7. Alkaloidsa) Pyridine & piperidineb) Tropanec) Quinolined) Isoquinolinee) Indolef) Steroidalg) Purine

a) Nicotiana, areca nutb) Coca, Belladonna, Daturac) Cinchonad) Opium, Ipecace) Ergot, Nuxvomica, Rauwolfia, catharanthus, Physostigmaf) Kurchig) Tea, Coffee

8. Protein Gelatin, gluten etc

9. Vitamins Thiamine (B1), Riboflavin (B2), Ascorbic acid etc

10. Antibiotics Penicillin, streptomycin, tetracycline etc

11. Hormones Adrenaline, thyroxine etc

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• A natural substance is considered as food if it fills stomachin every day life without any harmful effect.

• A substance becomes a drug if it changes a pathological ordisease state of human/ animal to normal physiologicalcondition having no undesirable effect in specific dose.

• A long-term studies (chemical, biological and physical etc)are required to establish whether a substance will beconsidered as drug or food or eliminate for consumption.Those studies are referred to as evaluation.

Evaluation of drug means –• Identification• Determination of quality• Determination of purity

Evaluation of Drugs

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Cultivation

The identification can be established by careful observational studyof the collected drug, and then compared with authentic specimenby the collector.

Therefore, for proper identification of a drug from plant or animalsources, a collector must be educated about plant taxonomy andvery much experienced with his/her job.

Therefore, drugs from plants/animals are identified by –

o A qualified, specialized & experienced person

o Comparison with the authentic sample specimen.

In every country, there is a national herbarium where most of plantsspecimen are preserved. A number of specialists are working onplant identification there.

Identification

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Quality• The word “quality” refers to the intrinsic value of the drug, i.e.,

the amount of medicinal principles or active constituentspresent. These principles are classified as carbohydrate,alkaloid, glycoside, volatile oil, lipid, antibiotics and steroids etc.

• A high grade of quality in a drug is of primary importance. Aneffort should be made to obtain and maintain high quality.

• To maintain high quality products one should do the following:1. Select proper source (wild or cultivated)2. Appropriate time of collection3. Collection of required parts of plants (bark, leaf, stem, rhizome,

root)4. Preparation of the collected drug by proper cleaning, drying.5. Proper preservation to avoid contamination by microorganisms

and moisture, heat, air and light.41

Purity

• The purity of drug can be achieved by –

1. Proper identification

2. Quality assurance.

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Evaluation Method

• The evaluation of a drug involves a number ofmethods, which may be classified as follows:

1. Organoleptic

2. Microscopic

3. Biological

4. Chemical

5. Physical

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1. Organoleptic evaluation of drug

• Organoleptic evaluation means the study of a drug withthe help of organs of sense.

• It includes any drug’s macroscopic or externalappearance, color, odor, taste & sounds of its fractureetc.

• The macroscopic or external characteristic of a drug maybe divided into 7 headings -

1. Shape2. Size3. Color4. Internal color5. Fracture6. Odor7. Taste 44

2. Microscopic evaluation of drug

Microscopic evaluation of drug can be done in the

laboratory by the use of microscopes and utilizes

various microscopic characters of the drugs,

such as types and arrangement of various cells and

tissues.

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3. Chemical evaluation of drug

• Chemical evaluation of drugs involves bothqualitative and quantitative determination of theiractive principles.

• In this method characteristic qualitative chemicaltests are employed to identify crude drugs and theirconstituents.

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4. Biological evaluation of drug

• The biological evaluation of crude drugs is very usefulin determining the pharmacological activity of the drug.

• Since living organism or their isolated living tissues areused, this method is also called the biological method orbioassay.

• Many drugs, particularly the antibiotics, toxins andtoxoids and also vitamins are assayed by this method.

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5. Physical evaluation of drug

The physical evaluation of crude drugs isaccomplished by the determination of various physicalcharacteristics using various physico-chemicaltechniques, for example, specific gravity (of fats andvolatile oils), melting points (of alkaloids), opticalrotation (of alkaloid and volatile oils), etc.

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• Following are different steps performed for preparation ofdrugs for market.

– Collection

– Harvesting

– Drying

– Garbling

– Packaging, storage, and preservation

Preparation of Drugs for Commercial Market

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1. CollectionCollection of drugs from cultivated plants always insures atrue natural source and a reliable product. This may, or maynot, be the case when drugs are collected from wild plants.Carelessness or ignorance on the part of the collector canresult in complete or partial substitution. This is especiallytrue when drugs arc difficult to collect or the natural source isscarce.Many drugs are collected from wild plants sometimes on afairly extensive scale (tragacanth, senna) when collection is thevocation of the gatherer, and sometimes on a limited scalewhen collection is an avocation (podophyllum, hydrastis).Because drugs come from all over the world, collection areasare almost universal, and collectors may vary fromuneducated natives to highly skilled botanists.

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1. Collection contd..

Time of collecting:

The proper time of collecting is particularly importantbecause the nature and quantity of constituents vary greatlyin some species according to the season.

The most advantageous collection time is when the part of theplant that constitutes the drug is highest in its content ofactive principles and when the material will dry to give themaximum quality and appearance.

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2. Harvesting

The mode of harvesting varies with each drug produced andwith the pharmaceutical requirements of each drug. Somedrugs may be collected by hand labor; however, when the costof labor is an important factor, the use of mechanical devicesis often more successful in economic production of the drug.

With some drugs, where the skillful selection of plant parts isan important factor (digitalis), mechanical devices cannotreplace hand labor.

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3. Drying

By drying the plant material, one removes sufficient moistureto ensure good keeping qualities and to prevent molding, theaction of enzymes, the action of bacteria, and chemicals orother possible changes.Drying fixes the constituents, facilitates grinding and milling,and converts the drug into a more convenient form forcommercial handling.Proper and successful drying involves two main principles:

Control of temperatureand

Regulation of air flow.

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3. Drying contd..

Control of the drying operation is determined by the nature ofthe material to be dried and by the desired appearance of thefinished product. The plant material can be dried either by thesun or by the use of artificial heat.

With some natural products, such as vanilla, processes offermentation or sweating are necessary to bring aboutchanges in the constituents. Such drugs require special dryingprocesses, usually called "curing."

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4. Garbling

Garbling is the final step in the preparation of a crude drug.Garbling consists of the removal of extraneous matter, such asother parts of the plant, dirt, and added adulterants.

This step is done to some extent during collection, but shouldbe carried out after the drug is dried and before the drug isbaled or packaged. Although garbling may be done bymechanical means in some cases, it is usually a semiskilledoperation.

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5: Packaging, storage, and preservationThe packaging of drugs depends on their final disposition.In commerce, if transportation, storage, and ultimate use formanufacturing purposes are involved, it is customary tochoose the type of packaging that provides ample protectionto the drug and gives economy of space.Leaf and herb material is usually baled with power balers intoa solid compact mass that is then sewn into a burlap cover.Senna leaves from India come in bales of 400 lb; stramoniumfrom Argentina in bales of 700 lb.Drugs that are likely to deteriorate from absorbed moisture(digitalis, ergot) are packed in moisture-proof cans. Gums,resins, and extracts are shipped in barrels, boxes, or casks.

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5: Packaging, storage, and preservation contd…

Proper storage and preservation are important factors inmaintaining a high degree of quality of the drug. Hard-packedbales, barks and resinous drugs usually reabsorb littlemoisture. But leaf, herb and root drugs that are not wellpacked tend to absorb amounts of moisture that reach 10, 15,or even 30% of the weight of the drug. Excessive moisture notonly increases the weight of the drug, thus reducing the %ageof active constituents, but also favors enzymatic activity andfacilitates fungal growth.Light adversely affects drugs that are highly colored,rendering them unattractive and possibly causing undesirablechanges in constituents.The oxygen of the air increases oxidation of the constituents ofdrugs, especially when oxidases are present. Therefore, thewarehouse should be cool, dark, and well ventilated with dryair. 57


The protection of drugs against attacks by insects must not beoverlooked. The insects that infest vegetable drugs belongchiefly to the orders Lepidoptera, Coleoptera, and Diptera.For destruction of insects and prevention of their attacks, anumber of methods have been employed.The simplest & the most efficient method is to expose thedrug to a temperature of 65°C which not only prevents insectattacks, but also many other forms of deterioration.For the fumigation of large lots of crude drugs, such as thosestored in warehouses and manufacturing plants, the use ofmethyl bromide has met with considerable success.Small lots of drugs may readily be stored in tight, light-resistant containers e.g. tin cans, covered metal bins, or amberglass containers.

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Drugs should not be stored in wooden boxes or in drawers andnever in paper bags. Not only is deterioration hastened, butodors are communicated from one drug to another, attacks byinsects are facilitated, and destruction by mice and rats mayoccur.

If drugs in small quantities are stored in tight containers,insect attack can he controlled by adding to the container afew drops of chloroform or CCl4 from time to time.

In the case of digitalis and ergot, whose low moisture contentmust be maintained at all times, the insertion of a suitablecartridge or device containing a non-liquefying, inert,dehydrating substance may be introduced into the tightcontainer.

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Because high temperatures accelerate all chemical reactions,including those involved in deterioration, drugs must alwaysbe stored at as low temperature as possible.

The ideal temperature is just above freezing, but since this isimpractical in most cases, the warehouse or other storageplace should be as cool as possible.

Certain drugs such as the biologics, must be stored at atemperature between 2 and 8ċ.

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Animal Drugs

Animal drugs are produced from wild or domesticatedanimals. Wild animals must be hunted (whale, musk deer) orfished for (cod and halibut), and thus, in a sense, theircollection parallels the collection of vegetable drugs.

Many animal drugs, however, are produced fromdomesticated animals &, therefore, correspond to thecultivated vegetable drugs. When drugs consist of insects, thedrugs are either collected from wild insects (cantharides) ordefinite attempts are made to cultivate them, i.e., to furnishthe insects with food and shelter and to maintain optimumconditions for their propagation (honeybee).

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Animal Drugs contd..

Drugs such as lanolin and milk products, as well as hormones,endocrine products, and some enzymes, are obtained fromdomesticated pigs, sheep, or cattle.

The slaughterhouse is the usual source of glandular productsand enzymes, and the larger packing establishments havedepartments for the recovery and refinement of thesetherapeutic agents and pharmaceuticals.

Processing and purification of the animal drugs vary with theindividual drug.

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• The term 'adulteration' or debasement of an article covers anumber of conditions, which may be deliberate oraccidental. Usually in crude drugs, this practice includessubstitution of the original crude drugs partially or fullywith other substances which is either free from or inferior intherapeutic and chemical properties.

1) Inferiority is a natural substandard condition (e.g. where acrop is taken whose natural constituent is below theminimum standard for that particular drug) which can beavoided by more careful selection of the plant material.

Adulteration of Crude Drug

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2) Spoilage is a substandard condition produced by microbialor other pest infestation, which makes a product unfit forconsumption, which can be avoided by careful attention tothe drying, and storage conditions.

3) Deterioration is an impairment of the quality or value of anarticle due to destruction or abstraction of valuableconstituents by bad treatment or aging or to the deliberateextraction of the constituents and the sale of the residue asthe original drugs.

4) Admixture is the addition of one article to another throughaccident, ignorance or carelessness e.g. inclusion of soil onan underground organ or the co-collection of two similarspecies.

Adulteration of Crude Drug contd..

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5) Sophistication is the deliberate addition of spurious orinferior material with intent to defraud; such materials arecarefully produced and may appear at first sight to begenuine e.g. powder ginger may be diluted with starch withaddition of little coloring material to give the correct shadeof yellow color.

6) Substitution is the addition of an entirely different article inplace of that which is required e.g. supply of cheapcottonseed oil in place of olive oil.

Adulteration of Crude Drug contd..

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Different methods used for adulteration may be grouped as follows:

1) Substitution with inferior commercial varieties.

2) Adulteration by artificially manufactured substitutes.

3) Substitution by exhausted drugs.

4) Substitution by superficially similar but cheaper natural substances.

5) Adulteration by addition of worthless heavy materials.

6) Addition of synthetic principles.

7) Usage of vegetative matter from the same plant.

Types of Adulteration Of Crude Drugs

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1. Substitution with Inferior Commercial VarietiesDue to morphological resemblance to the authentic drugs,different inferior commercial varieties are used asadulterant which may or may not have any chemical ortherapeutic potential as that original natural drug e.g.Arabian Senna (Cassia angustifolia), dog Senna (Cassiaobovata) and avaram (Cassia auriculata) have been used toadulterate Senna (Cassia senna); Japanese ginger (Zingibermioga) to adulterate medicinal ginger (Zingiber officinale).

2. Adulteration by Artificially Manufactured SubstitutesTo provide the general form and appearance of variousdrugs, some materials are artificially manufactured and areused as substitute of the original one, e.g. artificial invertsugar for honey; paraffin wax after yellow colorationsubstituted for bees wax. 67

Types of Adulteration Of Crude Drugs contd..

3. Substitution by Exhausted DrugsHere the same plant material is mixed which is having noactive medicinal components as they have already beenextracted out. This practice is most common in case ofvolatile oil containing materials like clove, fennel etc., wherethe dried exhausted material resembles the same likeoriginal drug (similarly with drugs like Cascara sagrada andginger). Sometimes when coloring matters have beenextracted or removed during exhaustion, the residue is re-colored with artificial dyes as is done with saffron and redrose petals.

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4. Substitution by Superficially Similar but Cheaper NaturalSubstancesUsually here the adulterated product has no relation withthe genuine article, may or may not have any therapeuticor chemical component desired, e.g. leaves of species -Ailanthus are substituted for belladonna, senna, mint etc.;Leaves of Phytolacca and Scopolia for belladona; Leaves ofXanthium for stramonium and dandelion for henbane;Indian dill with European dill or caraway etc.

5. Adulteration by Addition of Worthless Heavy MaterialsA large mass of stone mixed with Liquorice root, pieces oflimestone are found in asafoetida and lead shot hasoccurred in pieces of opium etc.

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6. Addition of Synthetic PrinciplesSometimes to fortify inferior natural products, syntheticprinciples are added e.g. adding citral to oil of lemon;benzyl benzoate to balsam of Peru etc.

7. Usage of Vegetative Matter from the Same PlantThis is done by mixing adventitious matters or naturallyoccurring with the drug in excessive amount or parts ofplant other than that which constitutes the drugs. Forexample liver warts and epiphytes growing in bark portionare mixed with Cascara or Cinchona; stems of buchu aresometimes cut into short lengths and added to the drug.

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• Besides being adulterated by different means as discussed earlier, thecrude drugs are prone to deterioration on storage. The shelf-life of crudedrugs are influenced by many factors which include not only the qualityof storage conditions but also the stability of the secondary (2°)metabolites present therein. Several factors are to be considered for thedetrimental effects on the stored products.

• Several primary environmental factors relating to storage can producedetrimental effects on stored products e.g.

1) Light,

2) Moisture / humidity,

3) Temperature &

4) Oxygen etc.

But more deterioration usually results from a combination of thesefactors, which leads to the development of living organism includingmolds, mites, bacteria etc. 71

Deterioration of Crude Drugs

1. Light

Photo-decomposition occurs with santonin, the principal constituents of

wormseed, which on exposure to light darkens and eventually becomes

black. In general, drugs should be protected by suitable light-proof

wrapping or by the use of amber colour containers. Powdered rhubarb

stored in clear glass jars rapidly changes as the exposed surfaces

turning from yellow to more reddish colour.

For these detrimental effects, WHO has specified that medicinal plant

materials requiring protection from light should be maintained in a

light resistant container that shields the contents from the effects of

light. Alternatively, the container maybe placed inside a suitable light

resistant (opaque) covering and/or stored in a dark place.

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Primary Factors for Deterioration

2. Moisture/HumidityMoisture present in drugs depends largely upon the amount of moisturein the atmosphere, which is usually expressed in the terms of humidity.When the atmosphere is completely saturated, the humidity is 100%,when half saturated it is 50% and so on. Drugs stored in non-airtightcontainers are termed air-dry and contain about 10-12% of waterdepending on the humidity of the atmosphere. This amount of water issufficient to activate the enzymes present in some dried plant materials,such as Digitalis and bring about the decomposition of the activeglycosides. Such drug should therefore be stored with a dehydratingagent or in sealed containers immediately after drying.Squill contains a hygroscopic mucilage and the powder there from, ifexposed to the atmosphere, will pickup moisture and become a stickymass.Therefore strict humidity control is necessary while storing; lowmoisture may be maintained, if necessary by the use of desiccant in thecontainer provided that direct contact with the product is avoided.

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Primary Factors for Deterioration contd..

3. TemperatureIt has a marked effect which is sometime unsuspected. Many enzymaticchanges in the plant secondary metabolites proceed more rapidly at theslightly raised temperature up to about 45°C. Obviously those drugscontaining volatile constituents in unprotected structures, e.g. plantsbelonging to Labiatae family and the petals of rose and chamomile allloose oil with an increase in temperature. Absorbent cotton woolcontains a small amount of fatty material which is the residualcomponent from the natural fiber. At a raised temperature thesemolecules become re-oriented, spreading themselves over the surface ofthe fiber to form an impervious layer. Thus cotton wool, once fullyabsorbent will gradually become completely non-absorbent because ofthe effect of temperature.

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4. Air Oxidation

Direct oxidation of the constituents of crude drug is sometime broughtabout by the oxygen of the air, e.g. Linseed oil rapidly becomeresinified as like the oil of Turpentine and oil of Lemon. Usually thisconversion is applied to the essential oil with terpenoid derivatives andwe can find the resinous deposit build-up around the stoppers used indispensing bottle containing this oil. Beside this, the rancidification offixed oils e.g. cod-liver oil, which involves the formation of unstableperoxides, is also an oxidative process. Thus, these types of materialsrequire storage in a well-filled, airtight container.

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• Living organisms usually develop in stored drugs where the conditionsare satisfactory for them. From a hygienic point of view, suchcontaminated material should be destroyed irrespective of whether ornot the active principles of drug have been effected. The more commonof such organisms belongs to the groups of bacteria, moulds, mites,nematodes, worms, insects etc.

1) Bacteria and Moulds

2) Mites and Nematode Worms

3) Insects/Moths

4) Coleoptera or Beetles

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Secondary Factors for Deterioration

1. Bacteria and MouldsDried herbs are particularly liable to be contaminated with the sporesof the bacteria and moulds, which are always present in the air. Undersatisfactory storage conditions their presence causes no problem, but itis generally accepted that the viable count permissible for crude drugsshould be the same as that for the food stuff. The effect produced bybacteria are not always very visible with the exception of somechromogenic species of bacteria, e.g. Bacillus prodigious, whichproduces red patches in starchy materials. However, bacterial growthis usually accompanied by the crude drug by growth of moulds whosepresence is quickly evident by the characteristic smell and by the massof clinging particles entrapped in the mycelial hyphae.

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Secondary Factors for Deterioration contd..

Dusty cotton wool, which is formed by bacterial attack causing thetrichomes to break into short length, rendered it to be very brittle. Inorder to identify a particular mould or bacteria, which is proliferatingin a stored product, it is necessary to culture it on a suitable mediumwith a view to obtain fruiting bodies for examination. However, if thedrug to be examined is infested rapidly, then it may be possible to makemicroscopic preparation directly from the sample. Usually the mouldsencountered with poorly stored drugs include the genera Mucor (e.g.grey mould, M. mused), Rhizopus (e.g. black mould, R. nigricans),Penicillium (e.g. blue mould, P. glaucum), Aspergillus (e.g. green mould,A. repens) and Saccharomyces.

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2. Mites and Nematode WormsIf found in stored drugs, mites are usually present in countless numbersupto 1.0 mm in length. Different mites found usually includeTyroglyphces siro (Cheese mite); Aleurobius farinae (Flour mite) andGlycyphagus spinipes (Cantharides mite). All these mites can beexamined microscopically by clearing the sample of powder containingthem with chloral hydrate reagent. The best known examples ofnematode worms are "Vinegar eel" − Turbatrix aceti, Anguillula aceti,Anguina tritici which are found in wheat flour or in the crude drugcontaining starchy materials. These worms are visible to the unaidedeye as minute threads continually curling and twisting in the mediumthey inhabit.

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3. Insects/Moths

A few species of the Lepidiptera attack the stored crude drugs andcause damage at the larval stage, where the infestation can spreadrapidly due to the mobility of the adults. The moths involved areunspectacular in appearance, 22-30 mm in length with off-white wingse.g. Ephestia kuehniella (Flour moth); E. ellutella (Cocoa moth).Besides this some other insects, cockroaches, ants and others aresometimes found to cause deterioration to the stored products.

4. Coleoptera or BeetlesThese are the insects that constitute the largest order of the animalkingdom comprising about 2,50,000, species of which about 600 havebeen found to be associated with stored food product or drugs.Stegobium paniceum is one beetle, which is found in many drugsincluding gentian, liquorice and rhubarb as well as leafy drugs andseeds. Belonging to the same family is Lasioderma serricorne (tobaccoor cigar beetle) which is reddish brown in colour, 2 to 2.5 mm in lengthand found in many stored crude drugs including ginger and liquorice. 80


• The container used for storage and its closure must not interactphysically or chemically with the material within in any way whichwould alter its composition. A well closed container must protect thecontents from extraneous matter or from loss of the material whilehandling and a tightly closed container must protect the material fromefflorescence, deliquescence or evaporation under normal condition ofhandling or storage. Storage area should be kept clean and spillages notallowed to enter cracks or in accessible crevices. Periodic spraying of thepremises with insecticides will help to prevent the spread of infestation.

• The principles, which apply to the control of infestation in warehouses,are equally applicable to small-scale storage. Good house keeping isutmost essential. Each stock should be inspected regularly and thematerial found to be contaminated is best to be destroyed by burning. Inthis respect a quick turn over to eliminate the effects of deterioration dueto both the primary and secondary factors as mentioned above aredesirable.

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Control Measures for Deterioration

• Cool, dry condition is the most suitable for the retardation of livingorganisms. As all leaves organisms require water for the development,perfectly dry drugs should be immune from secondary deterioration.Sometimes the crude drugs purchased by the herbalist may already havebeen sterilized, which is most commonly achieved by treatment of thebulk consignment with ethylene oxide or methyl bromide undercontrolled conditions.

– Drugs so treated, should comply with an acceptable limit for toxicresidues e.g. for Senna pods 50 ppm of ethylene oxide is the limit.

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Control Measures for Deterioration contd..

Ch 1 Pharma Cog Nosy Intro

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