Microbiology

1. History
Antony Van Leeuwenhock
Antony Van Leeuwenhock, (1632- 1723) of Holland who first observed and
reported bacteria.
His hobby was grinding lenses and observing diverse materials through them. His
microscope consists of a single biconvex lens that magnified object that about X
200. In 1683, he made accurate description of various types of bacteria ‘little
animalcules’ and communicated them to the Royal Society of London but the
significance of these observation was not realised.
It was only some two centuries later that their importance in medicine and biology
as a whole came to be recognised.
Louis Pasteur
Louis Pasteur (1822 - 1895), Founder or father of modern Microbiology
Pasteur of France was a trained chemist. His studies on fermentation led him to take an
interest in m/o. He established that fermentation was the result of microbial activity and
that diff types of fermentation were associated with diff types of m/o.
He and his students describe the techniques of bacterial cultivation and laid down three
principles.

2. Those include:
Every alternation of either wine or beer depends on development of m/o
The m/o are brought by the apparatus or ingredients use in the solution.
Whenever beer or wine contains no living organism, it remains unchanged.
He introduced techniques of sterilization and developed the steam steriliser, hot air oven
and autoclave.
He also established the differing growth needs of diff bacteria.
It was Pasteur who coined the term vaccine. The greatest impact in medicine was made
by Pasteur’s development of a vaccine for hydrophobia. This was acclaimed thru’out the
world.
He invented pasteurization, the heating of foods to elimate harmful m/o while retaining
not-harmful m/o.
An immediate application of Pasteur’s work was the introduction of antiseptic techniques
in surgery by Lister (1867).

3. Robert Koch, (Father of Medical Microbiology)
While Pasteur in France laid the foundations of microbiology, Robert Koch (1843-1910)
in Germany perfected bacteriological techniques during his studies on the culture and life
cycle of the anthrax bacillus (1876).
•Identified the bacteria that cause anthrax, tuberculosis, cholera
•Contributed significantly to the development of pure culture technique
•Introduction of agar to microbiology
•Introduced staining technique
Koch’s Postulates:
1. The microorganisms must be present in every case of the disease but absent from
healthy individuals.
2. The suspected microorganisms must be isolated and grown in pure culture.
3. The same disease must result when the isolated microorganism is inoculated into a
healthy host.
4. The same microorganism must be isolated again from the diseased host.