While studying Sarsaparilla, it was Seydler, a German scientist, who coined the
term Pharmacognosy in 1815 in his work entitled, "Analecta Pharmacognostica" from
combination of two Greek words viz, Pharmakon, a drug and gignosco, to acquire the
knowledge of. Further, Tschirsh made it more meaningful by restricting the term to the
utilization of products from natural sources. Thus, pharmacognosy is the subject of crude
drugs obtained from the plant, animal and mineral origins. It is the objective study of crude
drugs of the natural sources processed scientifically. The word 'crude drug' itself is selfexplanatory
and is used with the meaning of 'simple drug' and also as it exists in the natural
form. The crude drugs are plant or animal drugs that have undergone no other processes
than collection and drying.
Chapter 2 :-
Crude drugs obtained from different natural sources are used in treatment of a wide
spectrum of diseases. For their adequate study, it is necessary to arrange them in scientific
and systematic manner. Their huge number and varied occurrence make it difficult to put
them in a uniform pattern.
Chapter 3 :-
Either single or various parts of the same plant can be used as source of drug and hence
it becomes necessary to know various parts of a plant scientifically. Natural drugs may either
constitute cellular or a cellular organ of the plant. Cellular drugs are broadly known as
organized crude drugs; whereas a cellular drugs as unorganized crude drugs.
Chapter 4 :-
The Pharmacognostical study of crude drugs involves the use of several technical terms. It
is necessary to make students familiar with these terms by suitable examples.
Chapter 5 :-
After collection of the crude drugs, they are required to be processed prior to marketing.
The reasons for preparation of drugs are to stabilize them in transport and storage and to
ensure the absence of foreign organic matter and substitutes. The preparation of crude
drugs for market also takes care of pharmaceutical elegance. While preparing drugs for
commerce, several methods are adopted to meet the standard Pharmacopoeial
requirements. Generally, these methods include proper methods of collection and
harvesting, drying and garbling. Sometimes, coating and bleaching are also necessary for
converting the drug into suitable form. While doing so, it should be observed that neither
the action of the drug is lowered down, nor it is changed due to the additives used in the
process.
Chapter 6 :-
Adulteration is the debasement of an article. An adulterant resembles the genuine drug
in respect to its morphological appearance.
Chapter 7 :-
medicines. Later on he discovered that different plants possess different chemical
constituents. Till the beginning of era of natural product chemistry (i.e. middle of nineteenth
century), the plant derived products were not thoroughly known. In the present age of
modern analytical instrumentation like spectroscopy, mass-spectroscopy, NMR, these critical
difficulties were overcome and detailed information about the basic chemical constituents
present in plants are studied.
Chapter 9 :-
Pharmacognosy, the term fibre is used with restriction to describe certain characters
of plants or animals. With reference to the plant, they are elongated thick walled cells
with pointed ends, cell walls of which may consist of cellulose and may or may not
contain lignin. In medical practice, they are used as surgical dressings or ligatures.
The term fibre' is used with reference to surgical dressings made up of natural or
artificial origin. Apart from the three natural sources, (plant, animal and mineral), fibers are
now synthesized chemically from various materials.
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