Pasteur was one of the most accomplished scientists in the19th century. He conducted many exploratory studies and achieved great results. He used his whole life to prove three scientific problems: ① Every fermentation is due to the development of a microorganism. French chemists found that heating can kill those nasty microorganisms that make beer bitter. Soon, "pasteurization" was applied to various foods and drinks. (2) Every infectious disease is the development of a microorganism in an organism. Pasteur discovered and eradicated a bacterium that invaded silkworm eggs, thus saving the French silk industry. ③ Microorganisms of infectious diseases can reduce their virulence under special culture, thus transforming from germs into vaccines to prevent diseases. He realized that many diseases were caused by microorganisms, so he established the theory of bacteria.
Louis pasteur is praised by the world as "the most perfect person to enter the kingdom of science". He is not only a theoretical genius, but also a person who is good at solving practical problems. His two papers published in 1843-Study on Twin Phenomenon and Crystal Morphology initiated the study of optical properties of matter. From 1856 to 1860, he put forward a new theory of fermentation essence based on microbial metabolic activities. The Record of Lactic Acid Fermentation published by 1857 is a classic paper recognized by microbiology. After 1880, a variety of vaccines such as chicken cholera vaccine and rabies vaccine were successfully developed, and their theories and immunization methods caused great changes in medical practice. In addition, Pasteur's work also successfully saved the French wine industry, sericulture and animal husbandry.
Pasteur is regarded as the most important outstanding figure in the history of medicine. Pasteur's contribution involves several disciplines, but his reputation mainly focuses on defending and supporting germs and developing vaccines to prevent diseases.
Pasteur was not the earliest discoverer of bacteria. Before him, Kirula, Bao Henry and others had put forward similar assumptions. However, Pasteur not only enthusiastically and bravely put forward the theory about germs, but also proved the correctness of his theory through a large number of experiments, which convinced the scientific community. This is his main contribution.
Obviously, the cause lies in bacteria, so it is obvious that only by preventing bacteria from entering the human body can we avoid getting sick. Therefore, Pasteur emphasized that doctors should use disinfection. Joseph Sinter proposed to the world the use of disinfection in surgery, and he was influenced by Pasteur. Toxic bacteria enter the human body through food and drink. Pasteur invented a method of sterilizing beverages, which was later called pasteurization (heat sterilization).
At the age of 50, Buster focused on malignant carbuncle. It is an infectious disease that harms livestock and other animals, including people. Pasteur proved that the cause was a special kind of bacteria. He injected animals with attenuated Corynebacterium malignant carbuncle.
188 1 year, Pasteur improved the method of reducing the virulence of pathogenic microorganisms. He observed that animals who have recovered from infectious diseases will be immune to the disease in the future. Based on this, sheep and chickens were immunized with attenuated anthrax and chicken cholera pathogens respectively, which was successful. This method greatly aroused the enthusiasm of scientists. It is known that many infectious diseases can be avoided by this method.
1882, Pasteur was elected as an academician of the French Academy. In the same year, he began to study rabies, proved that pathogens existed in the saliva and nervous system of sick animals, and made a live virus vaccine, which successfully helped people gain immunity to diseases. According to Pasteur's immunization method, medical scientists have created vaccines to prevent several dangerous diseases, successfully avoiding the threat of typhus, polio and other diseases.
When it comes to rabies, people naturally think of Pasteur's well-known story. In the era when bacterial theory dominated, Pasteur did not know that rabies was a viral disease, but he knew from scientific practice that the toxicity of infectious substances would decrease after repeated generations and drying. He injected the medulla oblongata extract containing pathogenic rabies into rabbits many times, and then injected these attenuated venom into dogs, so that dogs could resist rabies virus infection with normal strength. 1885, a 9-year-old boy was seriously injured by a mad dog and was sent to Pasteur for rescue. After a moment's hesitation, Pasteur injected the child with the above extremely toxic extract, and then gradually injected the more toxic extract. Pasteur's idea is to make him resistant before the incubation period of rabies passes. As a result, Pasteur succeeded and the child was saved. 1886, another 15-year-old shepherd boy, Zhu Piye, was severely bitten and rescued while rescuing his companion who was attacked by a mad dog. Now, this sculpture describing the heroic deeds of this young man and the great achievements of Pasteur is located outside the Pasteur Institute in Paris. Pasteur invented the rabies vaccine in 1889. He also pointed out that this pathogen is a "filtering supermicroorganism" that can pass through a bacterial filter.
Pasteur's most famous achievement is to develop a technology to vaccinate people. This technology can protect people from the terrible rabies. Other scientists applied Pasteur's basic ideas to develop vaccines against many serious diseases, such as typhus and polio.
It is he who has done much more experiments than others and convincingly explained the process of microbial production. Pasteur also discovered the phenomenon of anaerobic life, that is, some microorganisms can survive in an environment lacking air or oxygen. Pasteur's research on silkworm diseases has great economic value. He also developed a vaccine against chicken cholera.
People often compare Pasteur with English doctor Edward Senna. Chen Na has developed smallpox vaccine, and Pasteur's method can and has been applied to the prevention and treatment of many diseases.
1In September, 854, the French Ministry of Education appointed Pasteur as the president of Lille Institute of Technology and the head of the Department of Chemistry. There, he became interested in the alcohol industry, and an important process of making alcohol is fermentation. At that time, an alcohol factory in Lille encountered technical problems and asked Pasteur to help study the fermentation process. Pasteur went deep into the factory and brought all kinds of beet root juice and fermentation broth back to the laboratory for observation. After many experiments, he found that there was a sphere much smaller than yeast in the fermentation broth, which grew up to be yeast.
After a period of time, the buds grow on the phyllodes, and when they grow up, they fall off and become new spheres. In this continuous cycle, the beet root juice is "fermented". Pasteur continued his research and found that alcohol and carbon dioxide gas produced during fermentation came from the decomposition of sugar by yeast. This process can even occur in the absence of oxygen. He believes that fermentation is the anaerobic respiration of yeast and controls its living conditions, which is the key link in wine making.
The Record of Lactic Acid Fermentation published by louis pasteur in 1857 is a classic paper recognized by microbiology.
From 65438 to 0880, louis pasteur successfully developed a variety of vaccines, such as chicken cholera vaccine and rabies vaccine, and their theories and immunization methods caused great changes in medical practice.
The founder of microbiology
Pasteur clarified the mystery of fermentation, and from then on Pasteur finally became a great microbiologist and the founder of microbiology.
At that time, the French beer industry was very famous in Europe, but beer often turned sour. The whole barrel of delicious beer turned into sour mucus and had to be dumped, which made the wine merchants complain and some even went bankrupt. 1865, the owner of a brewery in Lille asked Pasteur to help cure the disease of beer and see if a chemical could be added to prevent beer from turning sour.
Pasteur promised to study the problem. He observed under a microscope and found a spherical yeast cell in the liquid of aged wine and beer. When wine and beer turn sour, there will be lactobacillus in wine. It is this "bad guy" who breeds in nutritious beer and makes the beer "sick". He put the closed wine bottle in a wire basket, soaked it in water and heated it to different temperatures, trying to kill lactic acid bacteria without boiling beer. After repeated experiments, he finally found a simple and effective method: as long as the wine is kept at 50-60 degrees Celsius for half an hour, the lactic acid bacteria in the wine can be killed. This is the famous "pasteurization method", which is still in use today, and all sterilized milk sold in the market is.
At that time, the owner of the brewery didn't believe in Pasteur's method. Pasteur was in no hurry. He heated some samples, others didn't, and told the host to wait patiently for several months. As a result, the heated sample tastes pure after opening, while the unheated sample is very sour.
When Pasteur became a legend in France, sericulture in southern France was facing a crisis. A disease caused a large number of silkworm deaths, which severely hit the silk industry in the south. People turned to Pasteur for help, and Pasteur's teacher, Duma, encouraged him to take up the burden.
"But I have never dealt with silkworms!" Pasteur said uncertainly.
"Isn't that better?" Teacher Duma encouraged him to say.
When Pasteur thought that France would lose 654.38 billion francs every year because of silkworm disease, he no longer hesitated. As a scientist, he has the responsibility to save the endangered sericulture in France. Pasteur accepted the appointment of the Minister of Agriculture and went to Alai, a sericulture disaster area in southern France, on 1865.
Silkworm suffers from a mysterious and strange disease, which makes people feel very uncomfortable. Sick silkworms often hold their heads high and stretch their feet like cat claws to catch people. Silkworms are covered with brown and black spots, as if covered with pepper. Most people call this disease "pepper disease". Some sick silkworms died soon after hatching, and some struggled to survive to the third or fourth age, and finally died. Few silkworms cocoon, but the silkworms that can be drilled out are incomplete, and the offspring are also sick silkworms. The local sericulture people have tried everything, but they still can't cure the silkworm disease.
Pasteur observed with a microscope and found an oval brown particle that infected silkworms and mulberry leaves. Pasteur stressed that all infected silkworms and contaminated food must be destroyed and healthy silkworms must be used, starting from scratch. In order to prove the infectivity of "pepper disease", he used this pathogenic granule to brush mulberry leaves, and healthy silkworms got sick immediately after eating it. He also pointed out that the pathogens of silkworms placed on the shelf can be transmitted to the silkworms in the lower shelf through the falling silkworm droppings.
Pasteur also discovered another disease of silkworm-intestinal disease. The bacteria that cause this silkworm disease parasitize in the intestines of silkworm, making the whole silkworm black and die. A corpse is as soft as an air bag and perishable.
Pasteur told people that the method of eliminating silkworm disease is simple. By checking and eliminating the diseased moth, the spread of the disease can be stopped, and silkworms can be hatched without the eggs of the diseased moth. This method saved sericulture in France.
Pasteur invented many things in his life and made outstanding contributions to biological science and medicine. By chance, he found a panacea that could subdue chicken cholera.
Chicken cholera is a rapidly spreading plague, which is extremely fierce. Once the chickens raised at home are infected with chicken cholera, they will die in batches. Sometimes, people just saw some chickens foraging around. After a while, their legs suddenly trembled, then they fell down, struggled a few times and died. Some peasant women were happy to see the chickens alive when they closed their nests at night, but the chickens all died and lay in their nests the next day. 1880, a terrible chicken cholera epidemic occurred in rural France, and Pasteur was determined to subdue the plague.
In order to find out the cause of chicken cholera, Pasteur took the cultivation of pure chicken cholera bacteria as a breakthrough. He tried many cultural solutions. He concluded that the intestine of chicken is the most suitable breeding environment for chicken cholera bacteria, and the infectious medium is chicken feces. He tried many times, but all failed. In a daze, he had to relax, stop his research work and have a rest.
After a few days' rest, Pasteur began his research experiment again. At this time, he discovered the "New World". He inoculated the chicken with the old culture solution, but the chicken was not infected, as if the cholera bacteria had lost its effect on the chicken. What's going on here? Pasteur finally found that the toxicity of cholera bacteria gradually weakened due to the role of oxygen in the air. So, he injected healthy chickens with bacterial liquid for several days, 65,438+0 months, 2 months and 3 months, and made a set of comparative experiments. The mortality rates of chickens were 65,438 000%, 80%, 50% and 65,438 00% respectively. If the bacterial solution is injected for a longer time, the chicken will get sick, but it will not die. Things didn't end there. He also inoculated the same batch of chickens with fresh bacterial liquid. To his surprise, almost all the chickens inoculated with the old bacterial liquid were safe and sound, while those without the old bacterial liquid died completely. Practice has proved that all chickens injected with low-toxic bacteria solution and then injected with strong-toxic chicken cholera bacteria are also drug-resistant, and their condition is mild or even has no effect.
The method to prevent chicken cholera has been found! Pasteur's accidental discovery made him confirm the principle of attenuated immunization, which led to the idea of making anthrax vaccine. Although Chen Na, a British doctor, invented the vaccination method before him, he consciously cultivated and produced a successful immune vaccine, which was widely used to prevent many diseases. Pasteur was the first.
"Will, work and success are the three elements of life. Will will open the door to your career; Work is the way to enter the room; At the end of this road, there is a success to celebrate the results of your efforts ... As long as you have a strong will and work hard, you will have a successful day. " This is a famous saying of Pasteur about success.
The first victory
Pasteur was the son of a French cobbler and a veteran of Napoleon's army. His family was poor when he was a child. Pasteur is studious, clever and artistic, so he is likely to become a painter. However, at the age of 19, he gave up painting and devoted himself to science.
Pasteur first engaged in chemical research-about the optical properties of tartaric acid. He prepared 19 different tartrate and racemic tartrate crystals through experiments. When examined under the microscope, he found that these crystals can be divided into two kinds by mechanical methods-left-handed crystals and right-handed crystals, which have polarized light characteristics with the same optical rotation value but opposite optical rotation direction, thus revealing the "isomerism" of tartaric acid.
Pasteur's outstanding achievements in the field of chemistry have attracted people's attention and won the honor. However, he didn't just focus on the field of chemistry, but applied the principles and skills of experimental chemistry widely to fermentation problems, thus opening up a new era in the history of human science.
Immortal achievement
Fresh food will rot and deteriorate if left in the air for a long time, and microorganisms are found in it. Where do these microorganisms come from? At that time, there was a view that microorganisms originated from inanimate substances in food and solution and occurred naturally-spontaneous generation theory. Through his ingenious experiments, Pasteur strongly refuted those who hold this view.
Pasteur designed a gooseneck (curved neck bottle), which is now called Pasteur flask. The flask has a long bend that communicates with the outside air. Heat the solution in the bottle to the boiling point, and after cooling, air can re-enter. However, due to the downward bending of the long tube, the dust and microorganisms in the air can not contact with the solution, so that the solution remains sterile and the solution cannot rot for a long time. If the bottleneck is broken, the solution will deteriorate rapidly and a large number of microorganisms will appear. The experiment reached a convincing conclusion: the microorganisms in putrid substances came from the air, and the goose neck flask experiment also enabled Pasteur to create an effective sterilization method-pasteurization.
Pasteurization, also known as low-temperature sterilization, first heats the material to be sterilized to 65℃ for 30 minutes or 72℃ 15 minutes, and then quickly cools it to below 10℃. This will not destroy nutrients, but also kill bacteria plants. This method invented by Pasteur solved the problem of sour wine and saved the wine industry in France. In modern food industry, intermittent low-temperature sterilization is often used for sterilization. This shows the great achievements of Pasteur.
Pasteur began to study silkworm diseases, gradually solved the mystery of higher animal diseases, that is, diseases caused by germs, and finally conquered rabies, which threatened human beings for a long time.
From 1865 to 1870, he devoted all his energy to the study of silkworm diseases. This study involves two kinds of pathogenic microorganisms. After finding out the causes of silkworm diseases, Pasteur put forward reasonable and feasible control measures, thus freeing the French silk industry from the predicament.
Then, Pasteur devoted himself to the study of animal anthrax. He successfully isolated a pathogen from the blood of animals suffering from anthrax (such as cattle and sheep) and purified it, which proved that it was this pathogen that infected animals and led to their death. This is the germ theory of animal diseases. But at that time, doctors and veterinarians generally believed that diseases originated from animals, and diseases produced some toxic substances, and then, perhaps, these toxic substances were transformed into microorganisms. Later, Pasteur studied puerperal fever, a gynecological disease. He believes that this disease is caused by nurses and medical staff bringing microorganisms from infected women to healthy women, making them sick.
Therefore, although Pasteur was not a doctor, his contribution to medicine was immeasurable, and he laid the foundation of medical biology.
Pasteur not only studied anthrax, but also chicken cholera. This disease makes the mortality rate of chickens as high as over 90%. After many attempts, Pasteur found that this pathogenic microorganism could grow well on the culture medium made of chicken cartilage. 1 drop of fresh culture can kill 1 chicken quickly.
The most fortunate thing in Pasteur's research on this disease is that when a chicken is inoculated with old and stale culture, almost all chickens have only mild symptoms and recover quickly. When inoculated with fresh and toxic cultures, these chickens were very resistant to this disease, so Pasteur made his experimental chickens immune to chicken cholera. This can be compared with Qin Na's ability to use vaccinia to produce immunity to human smallpox.
After successfully studying the method of preventing chicken cholera, Pasteur began to study the method of dealing with anthrax. He cultivated anthrax in chicken soup at 42~43℃. In this way, pathogens will not form spores, so non-toxic strains are selected as vaccines for inoculation.
Pasteur was the first person in the world to successfully develop an attenuated anthrax vaccine, thus saving the endangered animal husbandry.
The pinnacle of glory
Pasteur's research on rabies vaccine in his later years was the glorious culmination of his career.
Rabies is not a common disease, but the mortality rate at that time was 100%. 188 1 year, pasteur set up a three-person team to develop rabies vaccine. In the process of finding the pathogen, although many difficulties and failures have been experienced, a highly toxic pathogen (a bullet-like baculovirus with a diameter of 25-800 nanometers) was finally found in the brain and spinal cord of rabies animals.
In order to get this virus, Pasteur often risked his life to extract it from sick animals. Once, in order to collect the saliva of a mad dog, Pasteur knelt at the foot of the mad dog and waited patiently. This lofty spirit of scientific research dedication, which puts life and death at risk, is not worth learning and praising by our future generations!
Pasteur continuously inoculated the isolated virus into the brain of rabbits and passed it on from generation to generation. A miracle happened when the rabies virus was injected into a healthy dog after 100 passages in the rabbit brain. Dogs are not sick. Dogs are immune.
Pasteur took out the rabies virus with spinal cord for many generations, hung it in a dry and disinfected hut, and naturally dried it 14 days to attenuate the virus. Then the spinal cord was ground into an emulsifying machine and diluted with normal saline to make the original Pasteur rabies vaccine.
1On July 6th, 885, a 9-year-old French child, Mester, was bitten by a rabid dog in 14. After the doctor diagnosed him, he was declared hopeless. However, Pasteur injected him with rabies vaccine every day. Two weeks later, the child turned the corner. Pasteur was the first person in the world to save his life from rabies. 1888, in recognition of his outstanding contributions, the pasteur institute was established, and he personally served as the director.
Pasteur's rigorous and scientific experimental design, his noble sentiment of being indifferent to fame and fortune, and his dedication to pursuing truth regardless of personal safety will remain in our hearts forever.
Pasteur has made immortal contributions to microbiology, immunology, medicine, especially microbiology, and is a well-deserved "father of microbiology".
Great patriotic feelings
Pasteur was an outstanding scientist in France in the19th century and the founder of microbiology. Because he invented the method of vaccination against infectious diseases, he made great contributions to the disease prevention and control of human beings and livestock and poultry raised by human beings. Because of his outstanding achievements in science, he enjoys a high reputation throughout Europe, and the University of Bonn in Germany solemnly awarded the honorary degree certificate to this famous scholar. However, after the Franco-Prussian War broke out, Germany occupied French territory. Out of deep affection for the motherland and deep hatred for the aggressor Germany, Pasteur resolutely returned the honorary degree certificate to Bonn University. He said: "Although science has no national boundaries, scientists have their own motherland." Hit the floor's words fully expressed a scientist's patriotic feelings, and thus became an immortal patriotic quote.