1st lecture for 1st year

1. PHARMACOGNOSY
Dr. Ahmed Metwaly
Lecture-1
(Introduction)

2. Objectives
Definitions
History
Nomenclature
Cultivation

3. Pharmacognosy
■ Is a science deals with natural medicinal drugs
which derived from natural sources.
■ the scientific study of the physical and chemical
characters of crude drugs of plant, animal, microbial
and mineral origin, also the extraction, preparation
and quality control of their active constituents and a
knowledge of their uses.
The word ‘Pharmacognosy’ is derived from: –
pharmakon ‘a drug’ (Greek) –
gignosco ‘ to acquire knowledge of’ (Greek) – or
cognosco ‘to know about’ (Latin)
• The term "Pharmacognosy literally means “acquire
knowledge of drugs”.

4. ■ Drugs:
Are chemical or biological substances used to treat, protect from diseases or
to promote better health.
■ Natural Products:
The biosynthetic substances (secondary metabolites) produced by living cells.
■ Synthetic Compounds:
The substances which do not occur in nature.
■ Crude Drugs or Raw Drugs:
The harvested and usually dried natural products before processing or
modification.
i.e. they exist as they occur naturally; not having been compounded or mixed
with other substances.

5. ■ Medicinal Plants:
Are those plants which have some medicinal activities.
■ Folk Medicine:
Folk medicine has evolved out of a blend of natures preventive and curative
principles and common sense.
Folk medicine emerged by trial and error methods.
■ Official Drugs:
is one which is listed and described in the Pharmacopoeia.
■ Pharmacopoeia:
A book recognized by the government as the legal authority for standards.
The first Egyptian Pharmacopoeia appeared in English in 1953, and in
Arabic in 1961.

6. Pharmacist should have a good knowledge of crude drugs because:
■ Many of them are still used as such. They proved to be medicinally
effective with minimum side effects.
■ Several them are the sources of chemical substances which cannot be
economically synthesized.
■ Some are the sources of chemical substances which form the starting
points for semi-synthetic products and their active constituents are used
by organic chemists as models for many synthetic substances.

7. Sources of Drugs:
■ Animal sources: Insulin from the pancreas of cattle an
used in treating diabetes. lanolin and milk products,
hormones, endocrine prods, and some enzymes.
■ Insect sources: Cantharides from beetles used as counter
irritant, bees honey has a great treating power.
■ Mineral sources: Compounds of mercury and silver are
used as antiseptics. Ca, P and Iron are given to provide
essential material for building bones and other
structures. Talc used as dusting powder.
■ Microbial sources: bacteria and fungi may be a great
source for natural medicinal drugs (eg. penicillin is a
metabolite of penicillium fungus )
■ Plant sources: Digitalis used for heart failure.

8. Classification of drugs for study
■ Alphabetical: The drugs are arranged in an alphabetical
order using either Latin or English names.
■ Taxonomic: The drugs are arranged according to the
plants from which they are obtained in phyla, orders,
families, genera and species.

9. ■ Morphological: The drugs are dividing into organized
drugs (leaves, flowers, fruits, seeds, herbs, roots and
rhizomes, barks, woods) and unorganized drugs (dried
lattices, extracts, gums, resins, oils, fats and waxes).
■ Chemical: The drugs are arranged according to their
important constituents e.g. drugs containing volatile
oils, glycosides, alkaloids, bitter principles, tannins).
■ Pharmacological or Therapeutic
The drugs are classified according to the pharmacological
action or their therapeutic use e.g. astringents, irritants,
carminatives………etc.

10. History of
Pharmacognosy
The medicinal use of plants
dates back to pre-historic
ages. The primitive man had a
good knowledge of the
vegetable kingdom of his
surroundings.

12. Traditional Chinese medicine

13. The Compendium of Materia Medica is a pharmaceutical text written by Li Shizhen
(1518–1593 CE)

20. Natural or Biological
origin or sources:
The binomial system is due to the Swedish
biologist Linnaeus.
In this system the first name is split with
Capital letter and denotes the genus, whilst
the second name denotes the species and
start with a small letter

21. ■ Except where the species is named after a person as Cinchona Ledgeriana
in which the species named after Charles Ledger, who brought its seed
from Brazil 1865., it was modified later to be small letter ledgeriana .
■ Both generic and specific names should be either written in italic or under-
lined.
■ In the Pharmacopoeias and research papers, botanical names are followed
by the names of persons. These refer to the botanist who first described
the species or variety.

22. The specific name is
usually indicates the
following:
Some characteristics of the plant, e.g.
■ Glycyrrhiza glabra, glabrous (smooth);
fruit is a smooth pod
■ Conium maculatum, maculate (spotted);
stem with reddish, spotted patches

23. ■ Barosma serratifolia and B. crenulata ,
serrate and crenulate; refers to the
margin of the leaf
■ Atropa belladonna, Bella (beautiful),
Donna (lady); the juice of the fruit
placed in the eyes causes dilatation of
the pupils, thus giving a striking
appearance
■ Hyoscyamus muticus, muticus (short);
the plant being short

24. ■ Rheum palmatum, palmate
(spreading); the large
spreading leaves
■ Pergularia tomentosa,
tomentose (hairy); numerous
hairs covering the plant

25. ■ Cimicifuga racemosa, racemes
(inflorescence); the flower in racemes
■ Strychnos potatorum, potable (fit to drink);
the seeds used in India for clearing of water
■ Agropyron repens, repens (creeping); the
creeping characters of the stem

26. A characteristic color, e.g.
■ Brassica alba (white),
■ Brassica nigra and Piper nigrum
(black),
■ Veratrum viride (green),

27. ■ Digitalis lutea (yellow),
■ Digitalis purpurea (purple)
■ Citrus aurantium (golden-yellow),

28. ■ Certain aroma of the plant, e.g.
Myristica fragrans, fragrant (nice aroma)
and Caryophyllus aromaticus (aroma)
■ A geographical source, e.g.
Cannabis indica and Tamarindus indica (India),
Olea arabica (Arabia),
Hydrastis Canadensis (Canada)
and Hamamelis virginiana (Virginia)

29. ■ A pharmaceutical activity,
■ e.g. Ipomoea purga (purgative),
■ Papaver somniferum (inducing sleep),
■ Brayera anthelmentica (expelling worms),
■ Strychnos nux vomica (nut causing vomiting)

30. ■ An active constituents,
■ e.g. Quillaia saponaria (containing saponins)
■ A special indication,
■ e.g. Triticum vulgare and Foeniculum vulgare (wild)
■ and Allium sativum, Negilla sativa and Crocus sativa (cultivated)

31. The generic name may also indicate certain
characters of the plant, e.g.
■ Iris, from the Greek, meaning Goddess of the
rainbow, indicating the varied colors of the
flowers
■ Atropa, from Atropos, the name of the Greek
fate who cuts the thread of life, indicating the
poisonous effect of the plant
■ Glycyrrhiza, glycyr from glucose (sweet) and rhiza
(root)
■ Linum, from Latin, linea meaning thread; referring
to the use of its fibres

32. ■ Geographical origin or sources:
■ The geographical source or Habitat is the region in which
the plant or animal yielding the drug
■ Indigenous plants (Native plants): Plants growing in their
native countries, e.g. Hyoscyamus muticus of Egypt,
Cannabis sativa of India.
■ Exotic plants: Plants not of native origin.

33. Wild plants
A wild plant is any plant which is growing wild
Cultivated plants
A cultivated plants is any plant grown for its produce

34. Summary
■ Definitions
■ History
■ Nomenclature

35. QUESTIONS?