CLASSIFICATION

1. Classification of Plant Drugs
SUBJECT: Pharmacognosy
COURSE: B PHARMACY IV SEMESTER
FACULTY NAME: Dr Manisha Bhatia
ASSOCIATE PROFESSOR
MMCP,MMU, Mullana

2. Classification of Plant Drugs
 1. For scientific & systematic study of crude drug it is
essential to classify them in a proper system.
 2. Generally drugs are classified as organised &
unorganised. according to whether they contain a
regularly organized cellular structure or not.
 Unorganised crude drug doesn’t contain cells but
cellular prdt either solid or liq
 This classification is to identify grp, name,
manage, remember. But this system of classification
is not appropriate.
 3. So we need to put stress on the classification of
drugs in a better way.

3. Classification of Plant Drugs
 The number of drugs is too large so necessary to
study them in a sequence of arrangement
 Alphabetical
 Taxonomic
 Morphological
 Pharmacological/Therapeutic
 Chemical/Biogenic
 Chemo-taxonomical

4. Alphabetical Classification
 Arranged acc to alphabets in two languages i.e English
& Latin
 Simple system adopted by several books &
Pharmacopoeia
 Latin/vernacular names
 Advantage: quick reference
 It is simple method, in this system location, tracing and
addition of the drug is easy
 No technical person is required for handling the
system.
 Used in Dictionaries & Pharmacopoeias

5.  Disadvantage:
 A) No indication of the interrelationships between
plants (drugs)
 B) No idea about the identity of the drug. Scientific
nature of the drug cannot be identified by this method,
whether they are organised or unorganised drug.
 C) This system does not help in distinguishing the
drugs of plant, animal and mineral source. (Original
source is not clear)

6. Alphabetical Classification
 1.Indian Pharmacopoeia.
 2. British Pharmacopoeia.
 3. United States Pharmacopoeia & National
Formulary.
 4. British Herbal Pharmacopoeia.
 5. British Pharmaceutical Codex.
 6. European Pharmacopoeia (Latin titles).
 7. Encyclopaedia of common Natural
ingredients used in drugs and cosmetics.

7. Taxonomic Classification
 Plants & animals are classified based on their botanical
classification.
 The drugs are classified according to plants or animals
from which they are obtained in Phyla, Orders,
Families, Genera, Species, Sub-species, etc.
 Advantage: Precise & ordered arrangement (no
ambiguity)
 Based on the principle of natural relatioship or
phylogenetic similarities

8. Taxonomic Classification
 Disadvantage:
 Botanical knowledge decreases over the years in
students
  < popular with teaching
 This system of classification is criticised for its failure
to recognize the organized and unorganized nature of
crude drugs and chemical nature of active constituents
and therapeutic significance of crude drugs

9. Taxonomic Classification
 Phylum - Spermatophyta
 Division - Angiospermae
 Class - Dicotyledons
 Order - Rosales
 Family - Leguminosae
 Sub-family - Papilionaceae
 Genus - Glycyrrhiza, Astragalus, Myroxylon
 Species - Glycyrrhiza glabra, Astragalus gummifer, Myroxylon
balsamum.

10. Morphological Classifications
 (Plant) Drugs are divided into organized and unorganized drugs
 Based on plant morphology/ Classified acc to the part of the
plant used as drug
 The crude drugs are grouped according to the parts of the plants
or animal represented into organised and unorganised drugs.
 Advantage
 This type of classification is very useful in identifying the
adulterants used.
 This system of classification is more convenient for practical
study; especially when the chemical nature of the crude drug
is not clearly understood.
 Disadvantage
 Microscopical studies are needed to identify powdered herbs
 It does not give an idea about biological source, chemical

11. Morphological Classifications
 Organised (Cellular):
 • Drugs are the direct parts of the plant and are divided into
leaves, barks wood, root, rhizome, seed, fruit, flower, stem, hair
and fibers.
 Unorganised ( Acellular):
 Drugs are the products of plant, animal and mineral source and
they are divided into dried latex, dried juice, dried extracts, gums,
resins, fixed oils and fats, waxes, volatile oil, animal products,
minerals (Solids, liquids, semi solids etc).

12. Morphological Classification
 Organized drugs
 Leaves
 Flowers
 Fruits
 Seeds
 Herbs
 Whole organisms
 Woods
 Barks
 Rhizomes
 Roots
 Unorganized drugs
 Dried latices
 Extracts
 Gums
 Resins
 Oils
 Fats
 waxes

13.  Seeds - nux-vomica, strophanthus, isabghol, castor
 Leaves - senna, digitalis, vasaka, eucalyptus
 Barks - cinchona, kurchi, cinnamom, quaillia
 Woods - quassia, sandalwood, red-sanders
 Roots - rauwolfia, ipecacuanha, aconite, jalap
 Rhizomes - turmeric, ginger, valerian, podophyllum
 Flowers - clove, pyrethrum, saffron, artemisia
 Fruits - coriander, colocynth, fennel, bael
 Entire drugs- ephedra, ergot, cantharides, belladonna
 Dried latices- opium, gutta-percha, papain
 Resins & resin combinations - balsam of tolu, myrrh, asafoetida,
benzoin
 Dried juices - aloes, kino, red gum
 Gums - acacia, tragacanth, ghatti gum, guar gum
 Dried extracts- gelatin, catechu, agar & curare

14. Pharmacological/Therapeutic
Classification
 Plant drugs are grouped according to their
pharmacological action of the most important active
constituent in the plant or according to the drug’s
therapeutic use, regardless of their morphology,
taxonomical status or chemical relationships.

15. Pharmacological/Therapeutic
Classification
 Advantage:
 More relevant and mostly followed method
 This system of classification can be used for suggesting
substitutes of drugs, if they are not available at a
particular place or point of time.
 Disadvantage:
 The constituents of one drug may have more than one
therapeutic action (fall into numerous groups. E.g.
Flavonoids). All drugs which have same
pharmacological action are grouped regardless of
morphology or constituents.

16. Pharmacological/Therapeutic
Classification
 The drugs differing in MOA but having same pharmacological
effects are also grouped together, e.g. bulk purgatives, irritant
purgatives, emollient purgatives.
Drugs acting on GIT:
 Bitters - Gentian, Quassia, Cinchona
 Carminatives - Dill, Mentha, Cardamom
 Emetics - Ipecacuanha
 Anti-amoebiasis - Kurchi, Ipecauanha
 Bulk laxatives - Agar, Isapghula, Banana
 Purgatives - Senna, Castor oil
 Peptic ulcer - Derivatives of Glycyrrhitinic acid treatment
 (Liqourice and Raw banana)

17. Pharmacological/Therapeutic
Classification
Drugs acting on respiratory system:
 Expectorant - Liqourice, Ipecacuanha, Vasaka
 Anti-tussives - Opium (Codeine, Noscapine)
 Bronchodilators - Ephedra, Tea (Theophylline)
Drugs acting on CVS:
 Cardiotonics - Digitalis, Squill, Strophanthus
 Cardiac depressants - Cinchona (quinidine), Veratrum
 Vaso-constrictors - Ergot (ergotamine), Ephedra
 Anti-hypertensives - Rauwolfia

18. Pharmacological/Therapeutic
Classification
 Drugs acting on Autonomic Nervous System
 Adrenergic - Ephedra
 Cholinergic - Physostigma, Pilocarpus
 Anticholinergic - Datura, Belladonna
 Drugs acting on Central Nervous System
 Central analgesic - Opium (morphine)
 CNS depressant - Belladonna, Opium, Hyoscyamus
 CNS stimulant - Tea, Coffee

19. Biogenic/Chemical Classification
 Drugs are classified according to the main active chemical
constituent available in the plant.
 Crude drugs are divided into different groups according to the
chemical nature of their most important constituents and the
biosynthetic pathways of the main active constituent.
 Irrespective of the morphological or taxonomical characters, the
drugs with similar chemical constituents are grouped together.
 Advantage:
 Popular for teaching when Pharmacognosy is phytochemically
based.
 Preferred method of classification, since therapeutic and
pharmacological significance is based on the chemical
composition of crude drugs.

20. Biogenic/Chemical Classification
 Glycosides - Digitalis, senna, cascara, liqourice
 Alkaloids - Nux vomica, ergot, cinchona, datura
 Tannins - Myrobalan, pale catechu, ashoka
 Volatile oils - Peppermint, clove, eucalyptus, garlic
 Lipids - Castor oil, bees wax, lanolin, cod liver oil, kokum
butter
 Carbohydrates - Acacia, agar, guar gum, pectin, honey,
isapghula
 Resins - Colophony, jalap, Balsam of Tolu
 Vitamins & Yeast, Shark liver oil, Oxytocin, Hormones
insulin
 Proteins & casein, gelatine, papain, trypsin

21. Biogenic/Chemical Classification
 Disadvantage:
 Ambiguities: Plants contain more than one group of
active constituents each with different actions.
 Ambiguities arise when particular drugs possess a
number of compounds belonging to different groups of
compounds.

22. CHEMOTAXONOMIC
CLASSIFICATION:
 Chemistry correlated to taxonomy i.e according to
taxonomy of the chemical constituents.
 The character most often studied in chemotaxonomy
are 20 metabolites of pharmaceutical significance
such as alkaloids, glycosides, flavonoids, etc.
 e.g. Presence of Berberine alkaloid in berberis,
argemone
 Presence of rutin, flavonoids in higher plants etc.

23. CHEMOTAXONOMIC
CLASSIFICATION:
 In this system of classification, the equal importance is
given for taxonomical status and chemical constituents.
There are certain types of chemical constituents which
are characteristics of certain classes of plants.
 Eg: Tropane alkaloids generally occur in most of the
members of Solanaceae
 Eg: Volatile oils occur in the members of Umbelliferae
and Rutaceae.

24. CHEMOTAXONOMIC
CLASSIFICATION:
 Based on the fact that their are certain
compounds which characterize certain particular
groups.
 Establishes the relation bween position of plant
in taxonomy & chemical nature of drugs.
 DNA hybridization & amino acid sequencing
are gaining inportance in this.

25. Adulteration of Crude Drugs
 Adulterant: herb which does not conform to official
standards.
 Usually practised when the herb is scarce or expensive
 Effects of Adulteration
 Inferiority
 Spoilage
 Admixture
 Sophistication
 Deterioration
 Substitution

26. Inferior Herb Quality
 Leads to a sub-standard herb
 Results naturally (in nature)
 Ignorance/carelessness
 E.g. Collection of genuine material regardless of the time factor
– collecting herbs prior/after ideal time
 Collection at incorrect stage of development
 E.g. coriander – fully ripe fruits (should be nearly ripe), clove
(flowers are in bud)
 Collection of parts which are not medicinally valuable e.g.
Chamomile leaves
 Collection of incorrect herb (close resemblance to indended
herb)
 Imperfect preparation (not removing undesired parts e.g. cork
from ginger rhizome/incorrect drying conditions)
 Incorrect storage: E.g. volatile oils: cool, dry place in air tight
containers

27. Herb Spoilage
 When the quality or medicinal value/usefulness
of herb is impaired or destroyed
 Bacterial/fungal action, insects, rodents
 Normally results from incorrect storage (effects
of water/temperature)
 Any herb which has been contaminated for
bacterial/fungal growth should be rejected

28. Deterioration
 Value or quality of the herb has been impaired
 Extraction/Destruction of medicinal actives
 Occurs commonly when the herb is expensive, limited or
needed for numerous purposes
 E.g. Ginger: removal of medicinally active constituents in
making ginger beer (cooking purposes)
 Aging
 Heat
 e.g. Volatile oils
 Moisture
 Light  oxidation (promotes the destruction of VitA)

29. Admixture
 When herbs of another species are added to the
medicinally valuable herb
 May be intentional
 OR
 Result of collection due to unskilled labour
 Presence of plant parts other than those allowed by
the definition E.g. excessive stalk
 Collection of foreign material (stones, dirt)
NOTE: Certain herbs may be legally mixed with inert
or other materials.

30. Sophistication
 Addition of inferior material with the intention
to decrease medicinal action of herbs.
 E.g. Candle wax coloured yellow and being
offered as Beeswax.
 E.g. Addition of flour to powdered ginger with
chillies for potency.

31. Substitution
 Adding an allied drug, or one which is
botanically different.
 E.g. Digitalis thaspi for Digitalis purpurea