Ninety-four years ago today (September 3, 1928), Fleming, a famous British bacteriologist and medical scientist, discovered penicillin, which opened the way for the use of antibiotics to treat infectious diseases and marked a new era for mankind to synthesize new drugs.
How is penicillin produced? What is the significance of the creation of penicillin?
A chance discovery
In the summer of 1928, the weather in the British Isles was particularly sultry - and the Wright Research Centre at St. Mary's Medical School, University of London, took an exceptional summer break. Alexander Fleming (1881-1955), a professor of bacteriology, was ready to go on vacation to the seaside without even packing up the disorganized vessels on his lab bench - for the first time in his many years of research. Fleming crossed into the lab he had left for days. "Oh no, mold is growing!" Fleming carefully took out one of the vessels for culturing bacteria, and when he reached the fifth one, he suddenly shouted in surprise.
Previously, Fleming had extracted staphylococci from the patient's pus and cultured them in glassware containing jelly, and the multiplying staphylococci, which he called "golden goblins," appeared densely on the jelly. This "golden goblin" caused boils, carbuncles, osteomyelitis, and food poisoning, and was very difficult to deal with. He cultivated it in order to find a way to kill it. Now, he saw a place in the glass vessel with green mold, and began to spread around the vessel, so he shouted in alarm.
If the culture solution is contaminated and moldy, it can no longer be used for experiments. The usual practice is to pour it out in one go. But Fleming did not do so, he wanted to see which kind of mold is messing up. So he picked up the petri dish to take a closer look, to understand why the moldy culture can no longer be used. Against the bright light, he found a peculiar phenomenon: in the lime green mold around a circle of blank flowers - the original growth of the "Golden Goblin" is missing!
Fleming immediately realized that something remarkable might have appeared. He excitedly and quickly scraped out from the culture vessel - a little mold, carefully placed under the microscope to observe. Through the thick lens, he finally found that this can kill the "Golden Goblin" green mold is Penicillium. Subsequently, he isolated the Penicillium. He also found that the "golden leprechaun" would be "deterred" every time before it had a "short encounter" with Penicillium. -In front of the penicillium 2.5 cm "camped".
Fleming continued to multiply many Penicillium in the culture, and then dripped the filtered culture into the "Golden Goblin". A miracle - within a few hours "golden goblins" all dead. He diluted the culture solution by 1/2, 1/4 ...... up to 1/800, and put each drop into the "golden goblin". As a result, he found that the "golden goblins" are all "dead". He also found that the green mold flowers can also kill diphtheria bacteria, anthrax, streptococcus and pneumococcus, etc. - Penicillium has a strong and extensive bactericidal effect was confirmed by similar experiments.
Fleming announced his findings on September 15, 1928, at St. Mary's School of Medicine. He also presented a paper on the subject, "Penicillin - Its Practical Application," to the London Medical Club on February 13, 1929, and it was published in the New England Journal of Medicine.
Magical yellow powder
When did humans use penicillin on a large scale? It was at least after 1939, that is to say, there was a gap of a few years between the discovery of the drug in 1928 and its actual use. What did we do in these ten years?
It was in the 1940s that penicillin was really used in clinical treatment, thanks entirely to the work of the Oxford pathologist Howard Walter Florey (1898-1968) and the biochemist ErnstBoris Chain (1906-1979).
Born in Australia in 1898, Flory went to Oxford University in 1921 and later became a professor of pathology at Oxford. He conducted a systematic study of antibiotic substances known to be produced by microorganisms from 1938 to 1939. Fleming's discovery of penicillin was one of the substances that attracted his attention the most.
Flory spent a lot of energy, recruited a bunch of girls to give very low wages, on these girls to cultivate mycobacteria, at that time Oxford University, if you travel back to see, can not see, all the places that can contain water, whether it is a beaker or bathtub all in the cultivation of penicillium, these girls were called penicillium girls, they desperately try desperately try, at least to prove a little penicillin is effective, but we just talked about the dose problem is still not solved.
Humans were very lucky that the second moment of coincidence and mystery came soon after. One day a researcher under Florentine in the fruit market to buy fruit, found a cantaloupe in the corner full of mold, is already moldy, can not eat, but this experimenter look at the cantaloupe on the mold skeleton clear, look at it does not look like a pool of things look very strange, so immediately ran to the laboratory.
An experiment found that indeed this strain of Penicillium can increase the dose by more than two thousand times, which is a very lucky moment, of course, not only this person, at that time the Americans also involved, the United States of those big pharmaceutical companies also involved, so from one to more than two thousand times, to tens of thousands of times hundreds of thousands of times, so little by little to improve.
In 1939, he and Chinn, a German biochemist, decided to extract and purify penicillin, the active substance in Penicillium cultures, and after 18 months of hard work, they finally obtained 100mg of penicillin in yellow powder form with a purity sufficient for intramuscular injection into humans.
They found that adding a million times the solvent formulated as penicillin prevented the growth of streptococci in rats. Then they conducted human experiments, which started well, but before the bacteria in the patient's body was completely eliminated, the penicillin they had refined was used up, and although the patient eventually died, the effectiveness of penicillin had been fully demonstrated.
In the spring of 1940, they conducted several more experiments on animal infections, all with very satisfactory results. So in August of the same year, Chinn and Flory and others published the full results of their re-study of penicillin in the prestigious Lancet journal.
An important milestone in the history of antibiotics
The discovery of penicillin marked the beginning of the antibiotic era, the golden age of chemotherapy. After the massive application of penicillin, many diseases that once seriously harmed human beings, those once incurable scarlet fever, septic pharyngitis, diphtheria, syphilis, gonorrhea, and various tuberculosis, septicemia, pneumonia, typhoid fever, etc., were effectively suppressed.
The miraculous efficacy of penicillin opened a new way of thinking about the use of antibacterial substances to kill disease-causing bacteria in the human body. The discovery of penicillin prompted scientists to search everywhere in the world for new antibacterial substances.
In 1943, Dr. Waxman, a Russian-born biochemist, discovered another effective antibiotic, streptomycin. It was a substance produced by an actinomycete that grew in the soil and was effective in treating a number of diseases, including tuberculosis. Within just 20 years, dozens of other antibiotics were discovered, including chloramphenicol and chlortetracycline, each with its own effectiveness.
The widespread use of antibiotics has not only fully demonstrated its miraculous efficacy, but, at the same time, has also pointedly exposed its problems. After the total number of penicillin applications worldwide exceeded 100 million doses, the first report of death caused by penicillin appeared. Later, it was discovered that up to 10% of people had allergic reactions to penicillin and that certain bacteria were becoming resistant to penicillin.
Nevertheless, the discovery and successful application of penicillin remains an epoch-making achievement that opened the way for the use of antibiotics to treat infectious diseases. For this, Fleming, Flory and Chinn shared the 1945 Nobel Prize in Physiology or Medicine together.
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