PENICILLIN DISCOVERED ON 15 SEPTEMBER 1928 LATER DEVELOPED AWARDED NOBEL PRIZE 1945

  PENICILLIN DISCOVERED ON 

15 SEPTEMBER 1928

LATER DEVELOPED AWARDED

 NOBEL PRIZE 1945

 Penicillins are still widely used today, though many types of bacteria have developed resistance following extensive use.

Formula C9H11N2O4S


Alexander Fleming, who is credited with discovering penicillin in 1928.

Sample of penicillium mould presented by Alexander Fleming to Douglas Macleod, 1935
Starting in the late 19th century there had been many accounts by scientists and physicians on the antibacterial properties of the different types of moulds including the mould penicillium but they were unable to discern what process was causing the effect.[23]



 The effects of penicillium mould would finally be isolated in 1928 by Scottish scientist Alexander Fleming, in work that seems to have been independent of those earlier observations

.[24]

 Fleming recounted that the date of his discovery of penicillin was on the morning of Friday 28 September 1928.

[25] The traditional version of this story describes the discovery as a serendipitous accident: in his laboratory in the basement of St Mary's Hospital in London (now part of Imperial College), Fleming noticed a Petri dish containing Staphylococcus that had been mistakenly left open was contaminated by blue-green mould from an open window, which formed a visible growth.[26] There was a halo of inhibited bacterial growth around the mould. Fleming concluded that the mould released a substance that repressed the growth and caused lysing of the bacteria.[27]

Once Fleming made his discovery he grew a pure culture and discovered it was a Penicillium mould, now known to be Penicillium notatum. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of the Penicillium mould. Fleming asked C. J. La Touche to help identify the mould, which he incorrectly identified as Penicillium rubrum (later corrected by Charles Thom). He expressed initial optimism that penicillin would be a useful disinfectant, because of its high potency and minimal toxicity in comparison to antiseptics of the day, and noted its laboratory value in the isolation of Bacillus influenzae (now called Haemophilus influenzae).[26][28]

Fleming was a famously poor communicator and orator, which meant his findings were not initially given much attention.[26] He was unable to convince a true chemist to help him extract and stabilize the antibacterial compound found in the broth filtrate. Despite the lack of a true chemist, he remained interested in the potential use of penicillin and presented a paper entitled "A Medium for the Isolation of Pfeiffer's Bacillus" to the Medical Research Club of London, which was met with little interest and even less enthusiasm by his peers. Had Fleming been more successful at making other scientists interested in his work, penicillin for medicinal use would possibly have been developed years earlier.[26]

Despite the lack of interest of his fellow scientists, he did conduct several experiments on the antibiotic substance he discovered. The most important result proved it was nontoxic in humans by first performing toxicity tests in animals and then on humans. His following experiments on penicillin's response to heat and pH allowed Fleming to increase the stability of the compound.[28] The one test that modern scientists would find missing from his work was the test of penicillin on an infected animal, the results of which would likely have sparked great interest in penicillin and sped its development by almost a decade.[26]

Medical application[edit]

Florey (pictured), Fleming and Chain shared a Nobel Prize in 1945 for their work on penicillin.

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In 1930, Cecil George Paine, a pathologist at the Royal Infirmary in Sheffield, attempted to use penicillin to treat sycosis barbae, eruptions in beard follicles, but was unsuccessful. Moving on to ophthalmia neonatorum, a gonococcal infection in infants, he achieved the first recorded cure with penicillin, on November 25, 1930. He then cured four additional patients (one adult and three infants) of eye infections, and failed to cure a fifth.[29][30][31]

In 1939, Australian scientist Howard Florey (later Baron Florey) and a team of researchers (Ernst Boris Chain, Arthur Duncan Gardner, Norman Heatley, M. Jennings, J. Orr-Ewing and G. Sanders) at the Sir William Dunn School of Pathology, 

University of Oxford made progress in showing the in vivo bactericidal action of penicillin. In 1940, they showed that penicillin effectively cured bacterial infection in mice.[32][33] In 1941, they treated a policeman, Albert Alexander, with a severe face infection; his condition improved, but then supplies of penicillin ran out and he died. Subsequently, several other patients were treated successfully.[34]

Penicillin was discovered in 1928 by Scottish scientist Alexander Fleming.[3] People began using it to treat infections in 1942.[4] There are several enhanced penicillin families which are effective against additional bacteria; these include the antistaphylococcal penicillins, aminopenicillins and the antipseudomonal penicillins. They are derived from Penicillium fungi