Pasteurization (a process of toning and treating milk free of damage causing microbes) is the most common reference to the great chemist and biologist who ever lived on this earth, Louis Pasteur. He is a well known name in the medical world as well as for millions of people around the world. The French chemist was also a brilliant microbiologist known for his outstanding breakthroughs in medicines and invention of vaccines for diseases that were never known to be treated. Pasteur was the first man on earth to have discovered cure for dangerous puerperal fever and created the first type of vaccine for rabies and anthrax. Louis Pasteur made great discoveries in chemistry besides striking gold in microbiology. Chemical discoveries by Pasteur include the very famous molecular basis for the asymmetry of certain crystals. Pasteur will always be remembered even by future generations for his notable disease prevention theories and medicines.
Louis Pasteur Childhood
On 27 December, 1822 Louis Pasteur was born in a poor family of tanners in Dole, situated in the Jura region of France. Louis was brought up in Arbois town in eastern France. He received his degrees in Letters and Mathematical Sciences. Soon after this he got admitted to École Normale Supérieure, an elite college.
Career & Personal Life
In 1848 Pasteur became the professor of physics at Dijon Lycée. He stayed here for a short period before switching off to University of Strasbourg as a professor of Chemistry. He met and found his love in Marie Laurent, daughter of the university's rector, in 1849. On 29 May in the same year Pasteur married Marie with whom he had 5 children out of which only two survived to become adults. Pasteur’s three children died of typhoid. Losing his children was very tragic in Pasteur’s life which also made him firm in discovering cures for diseases like typhoid. Pasteur’s personal losses left a deep scar within him inspiring him to do something for incurable diseases and symptoms.
Pasteur started off his scientific career with chemistry. His first chemical quest was with nature of tartaric acid in 1848. A tartaric acid solution usually derived from living things, specifically wine sediment, was found to rotate the light polarization plane when light passed through it. Pasteur solved the mystery in tartaric acid and found that the acid when derived out of chemical synthesis had no such effect even when the chemical reactions seemed identical and elemental composition was also found to be the same. Pasteur’s discovery was a first time demonstration of chiral molecules by any scientist so far.
Pasteur had presented his doctoral thesis on crystallography which aroused great interest in W. T. Fuillet who came forward and helped Pasteur in his appointed as the professor of chemistry at the Faculté (College) of Strasbourg.
In 1854 Pasteur was made the Dean of the new Faculty of Sciences in Lille. In 1856 Pasteur was appointed as the administrator and director of scientific studies of the École Normale Supérieure (a very prestigious French higher education establishment).
Discoveries, Theories & Contributions
Pasteur was the first microbiologist ever to state that microbial function caused fermentation in food elements, etc. Pasteur further explained (and cleared doubts) that the growth in bacteria in foods or liquids was caused not due to spontaneous generation of bacteria but due to biogenesis which means growth of organisms from laid eggs. Pasteur explained that a closed container also contained microbes, which was possible due to their entry through dust spores. This theory given out by Pasteur is known as his very famous ‘Germ Theory’.
Pasteur soon found that expansion of microbes spoilt liquids and beverages like milk, wine and beer. He started doing tests and expanded his theories based on germ theory and discovered that heating of liquids like milk kills most of the microbes present in them. First tests were completed on 20th April 1862 with the help of Claude Bernard. Soon this liquid germ killing process was called as pasteurization.
Pasteur became worried (and greatly immersed in his experiments and thoughts) about liquid contamination. He found that micro-organisms infecting animals and humans can also cause diseases. Pasteur wanted to stop the entry of harmful micro-organisms into the human body which resulted in Joseph Lister developing antiseptic methods in surgery.
In 1865 it was found that silkworms were being affected and killed by parasitic diseases called pébrine and flacherie. Pasteur worked very hard to prove that it was the function of microbes that were attacking silkworm eggs and causing the diseases. Pasteur also stated that the only remedy would be to remove this microbe from silkworm nurseries to prevent the diseases.
Pasteur invented anaerobiosis which stated that there are some microbes that can survive without oxygen and air which was named the Pasteur Effect.
Pasteur worked on chicken cholera. While performing this research one of his cultures, including the responsible bacteria, was found to have spoiled and failed to bring the disease in some chickens which he was trying to infect with the disease. Pasteur tried to use these healthy chickens for later use but could not infect them even with fresh bacteria. He found that the already weak bacteria made the chicken immune to cholera in spite of showing mild symptoms of the disease.
Pasteur’s assistant Charles Chamberland was asked to vaccinate the chickens used in cholera research during Pasteur’s holiday. Charles failed to carry out the vaccination and left the chickens like they were. After returning from a month long holiday the 1 month old cultures made the chickens sick but did not make the infection fatal in the chickens. Instead the chickens recovered fully. Charles was shocked to see that and thought of throwing away the faulty cultures (he suspected some malfunction causing the chickens to recover which was usually not possible) but Pasteur stopped him. Pasteur quickly figured that the chickens would now be immune to the disease, quite like the animals at Eure-et-Loir that had recovered from anthrax. In 1870s Pasteur used his cholera immunization method on anthrax which was fast affecting cattle. Soon this discovery was thought of fighting and preventing other diseases.
Pasteur worked laboriously in bringing out artificially weakened diseases in his laboratories. He put chemical and microbiological combination in creating ‘vaccines’. Pasteur named his first discovered vaccine for rabies which he obtained by growing the virus in rabbits and then weakening the strength of the disease by drying-up the affected nerve tissue. Pasteur (taking a huge risk for not being a professional and a licensed physician) performed his first rabies vaccination on 6 July 1885 on a young boy of 9 who was bitten by a mad dog having rabies. Pasteur became very famous after this incident and was hailed as a genius, a hero who saved lives. However, there is said to be some controversy in Pasteur’s discovery as there is very little chance of contracting rabies after such an exposure.
Pasteur wrote several books and journals. He had also taken several notes in all of his tests, samplings and researches in his laboratory. Some of his notable and principal works include "Etudes sur le Vin", (1866); "Etudes sur le Vinaigre" (1868); "Etudes sur la Maladie des Vers à Soie" (2 vols., 1870); "Quelques Réflexions sur la Science en France" (1871); "Etudes sur la Bière" (1876); "Les Microbes organisés, leur rôle dans la Fermentation, la Putréfaction et la Contagion" (1878); "Discours de Réception de M.L. Pasteur à l'Académie Française" (1882); "Traitement de la Rage" (1886).
In 1895 Pasteur received Leeuwenhoek medal which is regarded as microbiology's highest Dutch honor in Arts and Sciences. Pasteur was handed over the prestigious Grand Croix of the Legion of Honor. The Pasteur Institute was created in his honour on 4 June 1887 and inaugurated on November 14, 1888. Université Louis Pasteur has also been named after him.
There are several streets named after him. A statue of Pasteur is built on the campus of San Rafael High School in San Rafael, California. A south Indian hill station named Ootakamund has a Pasteur Institute in honor of the great man.
Pasteur suffered from several heart strokes which started in 1868. He died on 28 September 1895. It is said that during his death Pasteur was engrossed in listening to the story of St Vincent de Paul, a renowned catholic Priest who was admired by Pasteur. Pasteur’s body was buried in the Cathedral of Notre Dame. His remains were made into a crypt in the Pasteur Institute in Paris which is remembered even today for his outstanding life saving works.