Before the 1940s, humans had not mastered a drug that could effectively treat bacterial infections with little side effects. At that time, if someone got tuberculosis, it meant that the person was going to die soon. In order to change this situation, researchers have made a long-term exploration, but the breakthrough in this respect stems from an unexpected discovery. ?
In modern times, British bacteriologist Fleming first discovered the world's first antibiotic-penicillin in 1928, and alexander fleming discovered penicillin by a lucky mistake.
1928, British scientist Fleming discovered penicillin for the first time in experimental research. However, due to the lack of advanced technology and in-depth understanding at that time, Fleming did not isolate penicillin alone.
From 65438 to 0929, Fleming published his research results. Unfortunately, this paper has not been paid attention to by the scientific community since it was published.
When observing the Petri dish with a microscope, Fleming found that the staphylococcus colonies around the mold had dissolved. This means that some secretions of mold can inhibit staphylococcus. Subsequent identification showed that the above mold was Penicillium punctatum, so Fleming called its antibacterial substance penicillin.
Unfortunately, Fleming has not been able to find a way to extract high-purity penicillin, so he cultured Penicillium strains on his behalf and provided them to British pathologist HowardWalterFlorey and biochemist ernst boris chain at 1939.
1938, the German chemist Ernst Boris ernst boris chain saw Fleming's paper in an old book, and began to do purification experiments. ?
Flory and Ernst Boris ernst boris chain re-experimented with penicillin in 1940. They injected eight mice with a lethal dose of Streptococcus, and then only four of them were injected with penicillin.
Within a few hours, only four mice treated with penicillin were still alive and well. Since then, a series of clinical experiments have confirmed the efficacy of penicillin on streptococcus, diphtheria and other bacterial infections.
Penicillin can kill bacteria without damaging human cells, because penicillamine contained in penicillin can hinder the synthesis of bacterial cell walls, leading to the dissolution and death of bacteria, while human and animal cells have no cell walls.
/kloc-in the winter of 0/940, Ernst Boris ernst boris chain extracted a little penicillin, which was a major breakthrough, but it was still far from clinical application. ?
194 1 year, the baton of penicillin purification was passed to Australian pathologist Walter Flory. With the assistance of the U.S. military, Flory isolated strains from the soil brought back by pilots from airports around the world when they went out to perform tasks, which increased the output of penicillin from 2 units per cubic centimeter to 40 units.
About 194 1 years ago, pathologist Howard Walter Florey Baron Florey and biochemist Ernst Boris ernst boris chain of Oxford University in England realized the separation and purification of penicillin and found its curative effect on infectious diseases. However, penicillin can cause allergic reactions in individuals, so skin tests must be carried out before application.
Most of the antibiotics used are extracted from microbial culture solution, and some are artificially synthesized. Because of the different chemical compositions of different kinds of antibiotics, their mechanisms of action on microorganisms are also very different, some inhibit the synthesis of protein, some inhibit the synthesis of nucleic acids, and some inhibit the synthesis of cell walls.
After a period of intense experiments, Flory and ernst boris chain finally extracted penicillin crystals by freeze-drying. Later, Flory discovered a mold that could extract penicillin from a melon in large quantities, and prepared the corresponding culture solution with corn flour. Driven by these research results, American pharmaceutical companies began to produce penicillin in large quantities in 1942.
By 1943, pharmaceutical companies had discovered the method of mass production of penicillin. At that time, Britain and the United States were at war with Nazi Germany. This new medicine is very effective in controlling wound infection.
1943 10, Flory signed the first batch of penicillin production contracts with the US military. Penicillin was born at the end of World War II, which quickly reversed the war situation of the Allies. After the war, penicillin was widely used, saving tens of millions of lives. By 1944, the supply of medicine was enough to treat all allied soldiers who participated in the war during World War II.
Because of this great invention, Fleming, Flory and Qian En won the 1945 Nobel Prize in Physiology or Medicine for "discovering penicillin and its clinical function".
1945, British chemist D.C. Hodgkin determined the molecular structure of penicillin by X-ray diffraction.
1On September 5th, 944, the first batch of domestic penicillin was born in China, which opened the history of antibiotic production in China. By the end of 200 1, China's annual output of penicillin has accounted for 60% of the world's annual output of penicillin, ranking first in the world.
In 2002, Birol and others put forward a model based on process mechanism, which comprehensively considered various physiological changes of microorganisms in the fermentation process and found that it was a very complicated process. In order to study the penicillin process more conveniently, Birol extended the unstructured model proposed by Bajpai and Reuss, which further simplified the model and facilitated the research.
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Extended information Penicillin is also known as penicillin G, penicillin, penicillin, penicillin sodium, benzylpenicillin sodium, benzylpenicillin potassium and benzylpenicillin potassium.
Penicillin is an antibiotic, and its molecule contains penicillamine, which can destroy the cell wall of bacteria and play a bactericidal role in the reproductive period of bacterial cells. It is an antibiotic extracted from Penicillium.
Penicillin belongs to β -lactam antibiotics (β-lactams), including penicillin, cephalosporins, carbapenems, monocyclic antibiotics and cephamycin antibiotics. Penicillin is a commonly used antibacterial drug. However, a skin test must be done before each use to prevent allergies.
strong function
Penicillin is an important antibiotic with high efficiency, low toxicity and wide clinical application.
Its successful development greatly enhanced the ability of human beings to resist bacterial infection, and led to the birth of antibiotic family. Its appearance ushered in a new era of treating diseases with antibiotics.
After decades of improvement, penicillin injection and oral penicillin have been able to treat pneumonia, meningitis, endocarditis, diphtheria, anthrax and other diseases respectively. After penicillin, antibiotics such as streptomycin, chloramphenicol, oxytetracycline and tetracycline are constantly produced, which enhances the ability of human beings to treat infectious diseases. But at the same time, the drug resistance of some bacteria is gradually increasing.
In order to solve this problem, researchers are currently developing more effective antibiotics, exploring how to prevent bacteria from acquiring drug resistance genes, and developing plant-based antibacterial drugs. ?
Penicillin can't tolerate the enzyme produced by drug-resistant strains (such as drug-resistant Staphylococcus aureus), and it is easy to be destroyed by it, and its antibacterial spectrum is narrow, which is mainly effective for Gram-positive bacteria. Penicillin g can be divided into potassium salt and sodium salt. Potassium salt cannot be directly injected intravenously, and the amount of potassium ion should be carefully calculated during intravenous drip to avoid the death caused by injecting hyperkalemia into human body to inhibit heart function.
Penicillin antibiotics have little toxicity. Because β -lactams act on the cell wall of bacteria, while human beings only have cell membranes without cell walls, they are less toxic to human beings. Except for severe allergic reaction, the toxicity is not obvious at general dose.
To use this product, intradermal test must be carried out first. Penicillin allergy test includes skin test and in vitro test, in which intradermal injection is more accurate.
Skin test itself has certain risks. About 25% of patients who died of anaphylactic shock died of skin test. Therefore, skin test or injection should be fully prepared for rescue.
When you switch to different batches of penicillin, you also need to do a skin test again. Dry powder can be stored for many years without failure, but injection and skin test solution are unstable, so fresh preparation is better. Moreover, for patients with renal excretion and poor renal function, the dose should be adjusted appropriately. In addition, local application has many sensitization opportunities, and bacteria are prone to drug resistance, so it is not recommended.
References:
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