How was penicillin discovered?

Question

I´m not asking who did,but how he did it.

Answer 1

It was sort of accidently discovered and scientists began experimenting to develop the shots around ww2. saved untold number of lives in that war.

But more recently some other scientists studying gorillas discovered that these animals had already discovered something much like pencillin thousands of years ago. Really, the scientists were curious about the practice that gorillas ocassionally return to their old bedding areas and would consume their own fecal matter. It turns out that it provided an important media for that medicinal kind of fungus like penicillin. They still use it when they are hurt. Makes you wonder if we have really progressed all that much.

Answer 2

* Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Answer 3

Sir Alexander Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928. At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum. Charles Thom, an American specialist working at the U.S. Department of Agriculture, was the acknowledged expert, and Fleming referred the matter to him. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of the Penicillium mold.

Answer 4

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Fleming was originally optimistic that penicillin would be useful as an antibacterial agent, as it was safe for the human body, yet potent. Later, in 1931, he changed his mind and decided that penicillin would not last in humans for the duration needed to kill harmful bacteria, and stopped studying it. In 1934, he began another few years of clinical trials and tried to find someone else to purify it.

Answer 5

"bacteriologist Alexander Fleming" found a mold had contaminated one of his experiments. To his surprise, the mold was an antibacterial agent that could kill many harmful bacteria. He named the active agent, penicillin.

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Fleming was originally optimistic that penicillin would be useful as an antibacterial agent, as it was safe for the human body, yet potent. Later, in 1931, he changed his mind and decided that penicillin would not last in humans for the duration needed to kill harmful bacteria, and stopped studying it. In 1934, he began another few years of clinical trials and tried to find someone else to purify it.

Researchers at Oxford University in England, including Howard Florey, Ernst Chain, and Norman Heatley experimented with Fleming's discovery of penicillin. They proved that penicillin would be both harmless and effective in mice, but did not yet have the volume of penicillin needed to treat people. Orvan Hess and John Bumstead were the first people to use penicillin to successfully treat a patient.

Penicillin saved the lives of many soldiers in World War II, but the supply was extremely limited, and the drug was rapidly excreted from the body, so the patients had to be dosed frequently. It was common practice at this point to save the urine from patients undergoing penicillin treatment so that the penicillin could be isolated and reused. Another agent, probenecid, was eventually found to prolong the duration of penicillin in the human body.

Fleming, Florey, and Chain were awarded the Nobel Prize in medicine in 1945 for the discovery and development of penicillin. Florey was openly worried about the possibility of a population explosion resulting from health care improvements and said that his work with penicillin was more of an interesting scientific problem than a way to help people. He did admit that the fact that it could help people was a good thing, but not why he was originally interested.

Andrew J. Moyer later discovered how to make large quantities of penicillin, patenting the process and advancing the fight against infectious diseases. In 1987, he was inducted into the National Inventors Hall of Fame for his process of creating penicillin in high quantity.

Answer 6

by accident. Can't remember who it was, but they were researching some kind of bacteria in a petri dish. Something that was left near it (can't remember what it was) went mouldy with the penicillin mold (Penicillin is made from a blue mold). They noticed that the bacteria in the petri dish had all died after coming into contact with this blue mold. They researched they mold and discovered it was an anti-biotic.

Answer 7

Penicillin is a product of the fungus Penicillium notatum. In 1928, Alexander Fleming, the discoverer of penicillin, was investigating the properties of bacteria. He was already well-known from his earlier work, and had developed a reputation as a brilliant researcher, but quite a careless lab technician; he often forgot cultures that he worked on, and his lab in general was usually in chaos. After returning from a long holiday, Fleming noticed that many of his culture dishes were contaminated with a fungus, and he threw the dishes in disinfectant. But subsequently, he had to show a visitor what he had been researching, and so he retrieved some of the unsubmerged dishes that he would have otherwise discarded. He then noticed a zone around an invading fungus where the bacteria could not seem to grow. Fleming proceeded to isolate an extract from the mould and named the agent penicillin.

Answer 8

The discovery of penicillin is attributed to Scottish scientist Sir Alexander Fleming in 1928 and the development of penicillin for use as a medicine is attributed to the Australian Nobel Laureate Howard Walter Florey.

However, several others had noted earlier the bacteriostatic effects of Penicillium: The first published reference appears to have been in 1875, when it was reported to the Royal Society in London by John Tyndall.[1] Ernest Duchesne documented it in his 1897 paper; however it was not accepted by the Institut Pasteur because of his young age. In March 2000, doctors at the San Juan de Dios Hospital in San Jose (Costa Rica) published manuscripts belonging to the Costa Rican scientist and medical doctor Clodomiro (Clorito) Picado Twight (1887–1944). The manuscripts explained Picado's experiences between 1915 and 1927 about the inhibitory actions of the fungi of genera Penic. Clorito Picado had reported his discovery to the Paris Academy of Sciences, yet did not patent it, even though his investigation had started years before Fleming's.

Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928.[2] At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum. Charles Thom, an American specialist working at the U.S. Department of Agriculture, was the acknowledged expert, and Fleming referred the matter to him. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of the Penicillium mold. Even in these early stages, penicillin was found to be most effective against Gram-positive bacteria, and ineffective against Gram-negative organisms and fungi. He expressed initial optimism that penicillin would be a useful disinfectant, being highly potent with minimal toxicity compared to antiseptics of the day, but, in particular, noted its laboratory value in the isolation of "Bacillus influenzae" (now Haemophilus influenzae).[3] After further experiments, Fleming was convinced that penicillin could not last long enough in the human body to kill pathogenic bacteria, and stopped studying penicillin after 1931, but restarted some clinical trials in 1934 and continued to try to get someone to purify it until 1940.[4]

In 1930 Cecil George Paine, a pathologist at the Royal Infirmary in Sheffield, attempted to treat sycosis – eruptions in beard follicles – but was unsuccessful, probably because the drug did not get deep enough. Moving on to ophthalmia neonatorum – a gonococcal infection in babies – he achieved the first cure on 25 November 1930. He cured four patients (one adult, three babies) of eye infections, although a fifth patient was not so lucky.[5]

In 1939, Australian scientist Howard Florey (later Baron Florey) and a team of researchers (Ernst Boris Chain, A. D. Gardner, Norman Heatley, M. Jennings, J. Orr-Ewing and G. Sanders) at the Sir William Dunn School of Pathology, University of Oxford made significant progress in showing the in vivo bactericidal action of penicillin. Their attempts to treat humans failed due to insufficient volumes of penicillin (the first patient treated was Reserve Constable Albert Alexander), but they proved it harmless and effective on mice.[6]

Some of the pioneering trials of penicillin took place at the Radcliffe Infirmary in Oxford. On March 14, 1942, John Bumstead and Orvan Hess became the first in the world to successfully treat a patient using penicillin.[7][8]

The challenge of mass-producing the drug had been daunting. On March 14, 1942 the first patient was successfully treated for streptococcal septicemia with U.S.-made penicillin. Half of the total supply produced at the time was used on that one patient. By June 1942 there was just enough U.S. penicillin available to treat ten patients.[9] A moldy cantaloupe in a Peoria, Illinois market in 1943 was found to contain the best and highest-quality penicillin after a world-wide search.[10] The discovery of the cantaloupe, and the results of fermentation research on corn-steep liquid at the Northern Regional Research Laboratory at Peoria, Illinois, allowed the USA to produce 2.3 million doses in time for the invasion of Normandy in the spring of 1944.

Penicillin was being mass-produced in 1944

Penicillin was being mass-produced in 1944

During World War II, penicillin made a major difference in the number of deaths and amputations caused by infected wounds among Allied forces, saving an estimated 12%–15% of lives.[citation needed] Availability was severely limited, however, by the difficulty of manufacturing large quantities of penicillin and by the rapid renal clearance of the drug, necessitating frequent dosing. Penicillins are actively secreted, and about 80% of a penicillin dose is cleared within three to four hours of administration. During those times, it became common procedure to collect the urine from patients being treated so that the penicillin could be isolated and reused.[11]

This was not a satisfactory solution, however; so researchers looked for a way to slow penicillin secretion. They hoped to find a molecule that could compete with penicillin for the organic acid transporter responsible for secretion such that the transporter would preferentially secrete the competitive inhibitor. The uricosuric agent probenecid proved to be suitable. When probenecid and penicillin are concomitantly administered, probenecid competitively inhibits the secretion of penicillin, increasing penicillin's concentration and prolonging its activity. The advent of mass-production techniques and semi-synthetic penicillins solved supply issues, and this use of probenecid declined.[11] Probenecid is still useful, however, for certain infections requiring particularly high concentrations of penicillins.[12]

The chemical structure of penicillin was determined by Dorothy Crowfoot Hodgkin in the early 1940s. A team of Oxford research scientists led by Australian Howard Florey, Baron Florey and including Ernst Boris Chain and Norman Heatley discovered a method of mass-producing the drug. Chemist John Sheehan at MIT completed the first total synthesis of penicillin and some of its analogs in the early 1950s, but his methods were not efficient for mass production. Florey and Chain shared the 1945 Nobel prize in medicine with Fleming for this work, and, after WWII, Australia was the first country to make the drug available for civilian use. Penicillin has since become the most widely-used antibiotic to date, and is still used for many Gram-positive bacterial infections.

[edit] Developments from penicillin

The narrow range of treatable diseases or spectrum of activity of the penicillins, along with the poor activity of the orally-active phenoxymethylpenicillin, led to the search for derivatives of penicillin that could treat a wider range of infections.

The first major development was ampicillin, which offered a broader spectrum of activity than either of the original penicillins. Further development yielded beta-lactamase-resistant penicillins including flucloxacillin, dicloxacillin and methicillin. These were significant for their activity against beta-lactamase-producing bacteria species, but are ineffective against the methicillin-resistant Staphylococcus aureus strains that subsequently emerged.

The line of true penicillins was the antipseudomonal penicillins, such as ticarcillin and piperacillin, useful for their activity against Gram-negative bacteria. However, the usefulness of the beta-lactam ring was such that related antibiotics, including the mecillinams, the carbapenems and, most important, the cephalosporins, have this at the center of their structures. Ondred Abumbumer also made further discoveries towards penicillin.[13]

Answer 9

The discovery of penicillin is attributed to Scottish scientist Sir Alexander Fleming in 1928 and the development of penicillin for use as a medicine is attributed to the Australian Nobel Laureate Howard Walter Florey.

However, several others had noted earlier the bacteriostatic effects of Penicillium: The first published reference appears to have been in 1875, when it was reported to the Royal Society in London by John Tyndall.[1] Ernest Duchesne documented it in his 1897 paper; however it was not accepted by the Institut Pasteur because of his young age. In March 2000, doctors at the San Juan de Dios Hospital in San Jose (Costa Rica) published manuscripts belonging to the Costa Rican scientist and medical doctor Clodomiro (Clorito) Picado Twight (1887–1944). The manuscripts explained Picado's experiences between 1915 and 1927 about the inhibitory actions of the fungi of genera Penic. Clorito Picado had reported his discovery to the Paris Academy of Sciences, yet did not patent it, even though his investigation had started years before Fleming's.

Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928.[2] At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum. Charles Thom, an American specialist working at the U.S. Department of Agriculture, was the acknowledged expert, and Fleming referred the matter to him. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of the Penicillium mold. Even in these early stages, penicillin was found to be most effective against Gram-positive bacteria, and ineffective against Gram-negative organisms and fungi. He expressed initial optimism that penicillin would be a useful disinfectant, being highly potent with minimal toxicity compared to antiseptics of the day, but, in particular, noted its laboratory value in the isolation of "Bacillus influenzae" (now Haemophilus influenzae).[3] After further experiments, Fleming was convinced that penicillin could not last long enough in the human body to kill pathogenic bacteria, and stopped studying penicillin after 1931, but restarted some clinical trials in 1934 and continued to try to get someone to purify it until 1940.[4]

Answer 10

Discovered by accident by Alexander Fleming (Scottish bacteriologist in London) when he was trying to find staphylococci bacteria in 1928. He was experimenting with bacteria in his lab, set a lab dis with bacteria near an open window and when he got back to his experiment, he found some mold blown in through the window onto the dish contaminating the bacteria. Instead of throwing his experiment away, he looked at it closely under a microscope and he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold (the Penicillium mold, the precursor to penicillin) and it was dissolving the deadly staphylococci bacteria.

Answer 11

In the Autumn of 1928, Alexander Fleming returned to his laboratory after a month's holiday.  On his work bench, he noticed that, during his absence, the lid of a culture plate containing staphylococcus bacteria - the cause of a number of diseases from boils to pneumonia - had snapped off and the plate was contaminated by a number of yeasts and moulds.

One of the moulds, penicillin notatum, had killed the staphylococcus in the area of the plate it had infiltrated.  He narrowed down the reason for its success to the presence of an active ingredient which he named penicillin after the mould.

Answer 12

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Fleming was originally optimistic that penicillin would be useful as an antibacterial agent, as it was safe for the human body, yet potent. Later, in 1931, he changed his mind and decided that penicillin would not last in humans for the duration needed to kill harmful bacteria, and stopped studying it. In 1934, he began another few years of clinical trials and tried to find someone else to purify it.

Researchers at Oxford University in England,  experimented with Fleming's discovery of penicillin. They proved that penicillin would be both harmless and effective in mice, but did not yet have the volume of penicillin needed to treat people. Orvan Hess and John Bumstead were the first people to use penicillin to successfully treat a patient.

Answer 13

First of all the medecine penicillin was discoverd by Alexander Penicillin.It was discovered accidentally.The latter was doing an experiment and it did not work and he left all the equipment as well as the contents in the petridish left outside itself.The following day when he come to in his laboratory he saw that the penicillin had killed all the bacteria and then experiments was carried out to confirm this.As we can see it was  a hasard.

Answer 14

checking Wow. 207 responses so far.

It was one of those scientific accidents.

Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928.[2] At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum.

Answer 15

a Scottish scientist, names Alexander Fleming was trying to grow some type of mold in a petri dish. It was growing fine when one day it stopped. He tried to see the cause of this effect, and he found something (now called penicillin) inside the petri dish. He tried growing the molds again without the "something" and it grew, but when he added the "something" the molds stopped growing. He discovered the penicillin and experimented it on many other types of germs and molds and bacteria, and it killed many of them. Penicillin is now used as a medicine.

Answer 16

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Fleming was originally optimistic that penicillin would be useful as an antibacterial agent, as it was safe for the human body, yet potent. Later, in 1931, he changed his mind and decided that penicillin would not last in humans for the duration needed to kill harmful bacteria, and stopped studying it. In 1934, he began another few years of clinical trials and tried to find someone else to purify it.

Researchers at Oxford University in England, including Howard Florey, Ernst Chain, and Norman Heatley experimented with Fleming's discovery of penicillin. They proved that penicillin would be both harmless and effective in mice, but did not yet have the volume of penicillin needed to treat people. Orvan Hess and John Bumstead were the first people to use penicillin to successfully treat a patient.

Penicillin saved the lives of many soldiers in World War II, but the supply was extremely limited, and the drug was rapidly excreted from the body, so the patients had to be dosed frequently . It was common practice at this point to save the urine from patients undergoing penicillin treatment so that the penicillin could be isolated and reused. Another agent, probenecid, was eventually found to prolong the duration of penicillin in the human body.

Answer 17

Penicillin was discovered by chance, after Fleming accidentally left a dish of staphylococcus bacteria uncovered for a few days. He returned to find the dish dotted with bacterial growth, apart from one area where a patch of mould (Penicillin notatum) was growing. The mould produced a substance, named penicillin by Fleming, which inhibited bacterial growth and was later found to be effective against a wide range of harmful bacteria. However, it was not until World War II that penicillin, the first antibiotic, was finally isolated by Howard Florey and Ernst Chain. Fleming, Florey and Chain received a Nobel prize in 1945, for their discovery which revolutionised medicine and led to the development of lifesaving antibiotics.

Answer 18

In 1928, bacteriologist Alexander Fleming made a chance discovery from an already discarded, contaminated Petri dish. The mold that had contaminated the experiment turned out to contain a powerful antibiotic, penicillin. However, though Fleming was credited with the discovery, it was over a decade before someone else turned penicillin into the miracle drug for the 20th century.

Much of Fleming's work focused on the search for a "wonder drug." Though the concept of bacteria had been around since Antonie van Leeuwenhoek first described it in 1683, it wasn't until the late nineteenth century that Louis Pasteur confirmed that bacteria caused diseases. However, though they had this knowledge, no one had yet been able to find a chemical that would kill harmful bacteria but also not harm the human body.

In 1922, Fleming made an important discovery, lysozyme. While working with some bacteria, Fleming's nose leaked, dropping some mucus onto the dish. The bacteria disappeared. Fleming had discovered a natural substance found in tears and nasal mucus that helps the body fight germs. Fleming now realized the possibility of finding a substance that could kill bacteria but not adversely affect the human body.

In 1928, while sorting through his pile of dishes, Fleming's former lab assistant, D. Merlin Pryce stopped by to visit with Fleming. Fleming took this opportunity to gripe about the amount of extra work he had to do since Pryce had transferred from his lab. To demonstrate, Fleming rummaged through the large pile of plates he had placed in the Lysol tray and pulled out several that had remained safely above the Lysol. Had there not been so many, each would have been submerged in Lysol, killing the bacteria to make the plates safe to clean and then reuse.

While picking up one particular dish to show Pryce, Fleming noticed something strange about it. While he had been away, a mold had grown on the dish. That in itself was not strange. However, this particular mold seemed to have killed the Staphylococcus aureus that had been growing in the dish. Fleming realized that this mold had potential.

Fleming spent several weeks growing more mold and trying to determine the particular substance in the mold that killed the bacteria. After discussing the mold with mycologist (mold expert) C. J. La Touche who had his office below Fleming's, they determined the mold to be a Penicillium mold. Fleming then called the active antibacterial agent in the mold, penicillin.

I borrowed this exerpt from an article I found at:

Answer 19

Penicillin was accidentally discovered  and the major credit for this should go to  his assistant who actually forgot to clean the petri dish after a trial by Alexander flemming and later when flemming returned he found that something had killed or rather stopped the bacterial growth..

many discoveries were actually mistakes that turned out to be favourable.. this being one of the most helpful ones to mankind..

Answer 20

Accidentally. Sir Alexander Fleming was examining a petri dish and noticed that all the growth of all bacteria around a particular blue-green mould in the dish had been inhibited. It was a discovery for which he eventually won the noble prize.

On the heels of this discovery Mary Hunt (aka "Mouldy Mary") was sent to local markets in an attempt to find the exact mould that Flemming had discovered in his petrie dish. Her search was ultimately successful; the mould in a watermelon she found is responsible for much of the penicillin that has been cultivated since.

Answer 21

The discovery of penicillin is attributed to Scottish scientist Sir Alexander Fleming in 1928 and the development of penicillin for use as a medicine is attributed to the Australian Nobel Laureate Howard Walter Florey.

However, several others had noted earlier the bacteriostatic effects of Penicillium: The first published reference appears to have been in 1875, when it was reported to the Royal Society in London by John Tyndall.[1] Ernest Duchesne documented it in his 1897 paper; however it was not accepted by the Institut Pasteur because of his young age. In March 2000, doctors at the San Juan de Dios Hospital in San Jose (Costa Rica) published manuscripts belonging to the Costa Rican scientist and medical doctor Clodomiro (Clorito) Picado Twight (1887–1944). The manuscripts explained Picado's experiences between 1915 and 1927 about the inhibitory actions of the fungi of genera Penic. Clorito Picado had reported his discovery to the Paris Academy of Sciences, yet did not patent it, even though his investigation had started years before Fleming's.Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928.[2] At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum.

Answer 22

In 1928, bacteriologist Alexander Fleming made a chance discovery from an already discarded, contaminated Petri dish. The mold that had contaminated the experiment turned out to contain a powerful antibiotic, penicillin. However, though Fleming was credited with the discovery, it was over a decade before someone else turned penicillin into the miracle drug for the 20th century.

On a September morning in 1928, Alexander Fleming sat at his work bench at St. Mary's Hospital after having just returned from a vacation at The Dhoon (his country house) with his family. Before he had left on vacation, Fleming had piled a number of his Petri dishes to the side of the bench so that Stuart R. Craddock could use his work bench while he was away.

Back from vacation, Fleming was sorting through the long unattended stacks to determine which ones could be salvaged. Many of the dishes had been contaminated. Fleming placed each of these in an ever growing pile in a tray of Lysol.

Much of Fleming's work focused on the search for a "wonder drug." Though the concept of bacteria had been around since Antonie van Leeuwenhoek first described it in 1683, it wasn't until the late nineteenth century that Louis Pasteur confirmed that bacteria caused diseases. However, though they had this knowledge, no one had yet been able to find a chemical that would kill harmful bacteria but also not harm the human body.

In 1922, Fleming made an important discovery, lysozyme. While working with some bacteria, Fleming's nose leaked, dropping some mucus onto the dish. The bacteria disappeared. Fleming had discovered a natural substance found in tears and nasal mucus that helps the body fight germs. Fleming now realized the possibility of finding a substance that could kill bacteria but not adversely affect the human body.

Answer 23

A scientist in 1928, Sir Alexander Fleming, discovered it accidentally when trying to find a way to kill  bacteria. However, he was not responsible for the revolutionary aid it gave to the medical world - Dr. Howard Florey expanded and increased the killing mechanisms in penicillin to make it most effective and usable in modern day hospitals.

Answer 24

Alexander Fleming discovered it in 1928 by accident when he was investigating the properties of staphylococci.

After returning from a long holiday, Fleming noticed that many of his culture dishes were contaminated with a fungus. He then noticed a zone around an invading fungus where the bacteria could not seem to grow.

Fleming proceeded to isolate an extract from the mould, correctly identified it as being from the Penicillium genus, and therefore named the agent penicillin.

Answer 25

basically he used a pertri dish and was discovering about different kinds of bacteria - and discovered penicillin by mistake. He left the dish open for a long period of time meaning it became contaminated by foreign substances including penicillium.

He noticed that around this patch of moud the bacteria had disappeared. Penicillin is only produced when the penicillium dies

Answer 26

Fleming recounted later that the date of his breakthrough was on the morning of Tuesday, September 28, 1928.[2] At his laboratory in the basement of St. Mary's Hospital in London (now part of Imperial College), Fleming noticed a halo of inhibition of bacterial growth around a contaminant blue-green mold Staphylococcus plate culture. Fleming concluded that the mold was releasing a substance that was inhibiting bacterial growth and lysing the bacteria. He grew a pure culture of the mold and discovered that it was a Penicillium mold, now known to be Penicillium notatum. Charles Thom, an American specialist working at the U.S. Department of Agriculture, was the acknowledged expert, and Fleming referred the matter to him. Fleming coined the term "penicillin" to describe the filtrate of a broth culture of the Penicillium mold. Even in these early stages, penicillin was found to be most effective against Gram-positive bacteria, and ineffective against Gram-negative organisms and fungi. He expressed initial optimism that penicillin would be a useful disinfectant, being highly potent with minimal toxicity compared to antiseptics of the day, but, in particular, noted its laboratory value in the isolation of "Bacillus influenzae" (now Haemophilus influenzae).[3] After further experiments, Fleming was convinced that penicillin could not last long enough in the human body to kill pathogenic bacteria, and stopped studying penicillin after 1931, but restarted some clinical trials in 1934 and continued to try to get someone to purify it until 1940

Answer 27

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Answer 28

Alexander Fleming, a Scottish bacteriologist in London, discovered penicillin by mistake when he was trying to study staphylococci bacteria in 1928. He was running experiments with the bacteria in his laboratory at London's St. Mary's Hospital, and set a laboratory dish containing the bacteria near an open window. Upon returning to the experiment, he found that some mold blown in through the open window onto the dish, contaminating the bacteria.

Instead of throwing away his spoiled experiment, Fleming looked closely at it under his microscope. Surprisingly, he saw not only the mold growing on the staphylococci bacteria, but a clear zone around the mold. The Penicillium mold, the precursor to penicillin, was dissolving the deadly staphylococci bacteria.

Fleming was originally optimistic that penicillin would be useful as an antibacterial agent, as it was safe for the human body, yet potent. Later, in 1931, he changed his mind and decided that penicillin would not last in humans for the duration needed to kill harmful bacteria, and stopped studying it. In 1934, he began another few years of clinical trials and tried to find someone else to purify it.

Researchers at Oxford University in England, including Howard Florey, Ernst Chain, and Norman Heatley experimented with Fleming's discovery of penicillin. They proved that penicillin would be both harmless and effective in mice, but did not yet have the volume of penicillin needed to treat people. Orvan Hess and John Bumstead were the first people to use penicillin to successfully treat a patient.

Penicillin saved the lives of many soldiers in World War II, but the supply was extremely limited, and the drug was rapidly excreted from the body, so the patients had to be dosed frequently. It was common practice at this point to save the urine from patients undergoing penicillin treatment so that the penicillin could be isolated and reused. Another agent, probenecid, was eventually found to prolong the duration of penicillin in the human body.

Fleming, Florey, and Chain were awarded the Nobel Prize in medicine in 1945 for the discovery and development of penicillin. Florey was openly worried about the possibility of a population explosion resulting from health care improvements and said that his work with penicillin was more of an interesting scientific problem than a way to help people. He did admit that the fact that it could help people was a good thing, but not why he was originally interested.

Andrew J. Moyer later discovered how to make large quantities of penicillin, patenting the process and advancing the fight against infectious diseases. In 1987, he was inducted into the National Inventors Hall of Fame for his process of creating penicillin in high quantity.