The Life Of LOUIS PASTEUR
The Life of LOUIS PASTEUR
Louis Pasteur was born on December 27, 1822, in D?le, a small town in France. He grew
in a humble family and his father was a tanner. He graduated in 1840 from the College of
Arts at Besancon and entered the prestigious Ecole Namale Supervieure, Paris, to work
for his doctorate degree. He chose for his studies the then obscure science of
crystallography, which was to have a great influence on his career.
Pasteur entered the scientific world as a professor of physics at the Lycee of
Tournon and started his research on the optical properties of crystals of tartaric
acid salts. He found the two forms of this acid which could rotate the plane of
polarization of light, one to the right and the other to the left. This was his first
important discovery in crystallography, the phenomenon of optical isomers. Paradoxically
it incited him to abandon the field. But it won the acclaim of the French Academy
and Britain’s Royal Society. Thus Pasteur became famous at the age of 26.
Pasteur soon began researching the complexities of bacteriology. The prevalent theory of
life at the time was spontaneous generation which states that certain forms of life such
as flies, worms, and mice can develop from non-living matter such as mud and decaying
fish. Pasteur disproved this theory with a simple experiment. He showed that
microorganisms would grow in sterilized broth only if the broth was first exposed to air
containing spores, or reproductive cells. His findings led to the development of the cell
theory of the origin of living matter which states that all life originates from
preexisting living material.
In 1849, Pasteur became professor of chemistry at the University of Strasbourg, where
he began studying fermentation, a type of chemical breakdown of substances by microbes.
He served the rest of his career as Dean of Sciences at the University of Lille.
Soon after his arrival at Lille, Pasteur was asked to solve the problems of the local
industries, vinegar and silk manufacture.
A producer of vinegar from beet juice wanted to know why the product was sometimes
spoilt. On examining the juice microscopically, Pasteur observed that the
contaminant, amyl alcohol, was optically active. This gave clear evidence that it was
produced by a living organism. Pasteur then proposed a biological interpretation
of the process of fermentation. He demonstrated that when no contamination by living
contagion took place, the process of fermentation or putrefaction did not take place.
Thus the celebrated techniques of Pasteurization, came into being, it could not only
preserve wine and milk but drastically cut inflation in the surgeon’s operating
table. Today pasteurization follows closely the early techniques of Louis Pasteur. In the
case of milk pasteurization, the milk is heated to 161?F for 15 seconds followed by a
rapid cooling to 50?F or lower. This process removes any unwanted bacteria, but also
kills any beneficial bac!
teria and reduces some of the nutritive property of milk.
The Franco-Prussian War opened an avenue to press his microbial theory of infection,
he got the grudging agreement of the military medical corps to sterilize instruments
and steam bandages. As a result, thousands of lives were saved. In 1873, Pasteur was
elected to the French Academy of Medicine, a spectacular achievement for a person
without a medical degree.
Pasteur was now ready to move from the simpler forms of life in the microbial
world to the diseases of the higher animals. The opportunity came through a
devastating outbreak of anthrax, a killer plague of sheep in 1876. Pasteur tried to
produce pure cultures, his objective was to fight the disease and not just to describe it.
Pasteur had accidentally forgotten in a corner of the laboratory a culture of fowl
cholera and noticed that it had lost some of its virulence. Then he vaccinated some
chicken which resisted the disease. The same technique, after improvement, was applied
against bacillus anthracis: sheep inoculated with the vaccine survived and the
non-vaccinated ones died. A scourge that had crippling economic effects was brought
under control. Simultaneously, the principle of immunization or the protection of the
body through vaccines was discovered.
In 1865, the silk industry of France faced an economic ruin by an epidemic among