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.
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Extended data:
1, basic information of penicillin
Chinese name: penicillin
Chinese alias: penicillin
English name: benzylpenicillin
English alias: cilloralpradupenUrsopen benzylpenicillin; cosmopen
Si Nuo. : 6 1-33-6
Molecular formula: C 16H 18N2O4S.
Molecular weight: 334.39000
Accurate mass: 334.09900
PSA: 1 12.0 1000
LogP: 1. 18960
2. Physical and chemical properties
Density:1.42g/cm3
Boiling point: 663.3? 760 mm Hg
Flash point: 355? C
Refractive index: 1.655
Storage conditions: low temperature ventilation and drying.
3. Safety information
Customs code: 3204 1900
WGKGermany:2
Hazard category code: R42/43
Safety instructions: S36/37
RTECS number: XH9700000
Dangerous goods sign: Xn
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