In 1874, physician Sir William Roberts noted that cultures of the mold Penicillium glaucum that is used in the making of some types of blue cheese did not display bacterial contamination.
Antibiosis was first described in 1877 in bacteria when Louis Pasteur and Robert Koch observed that an airborne bacillus could inhibit the growth of Bacillus anthracis.
Synthetic antibiotic chemotherapy as a science and development of antibacterials began in Germany with Paul Ehrlich in the late 1880s.
In 1895 Vincenzo Tiberio, Italian physician, published a paper on the antibacterial power of some extracts of mold.
In 1897, doctoral student Ernest Duchesne submitted a dissertation, "Contribution à l'étude de la concurrence vitale chez les micro-organismes: antagonisme entre les moisissures et les microbes" (Contribution to the study of vital competition in micro-organisms: antagonism between molds and microbes), the first known scholarly work to consider the therapeutic capabilities of molds resulting from their anti-microbial activity.
Ehrlich noted certain dyes would color human, animal, or bacterial cells, whereas others did not. He then proposed the idea that it might be possible to create chemicals that would act as a selective drug that would bind to and kill bacteria without harming the human host. After screening hundreds of dyes against various organisms, in 1907, he discovered a medicinally useful drug, the first synthetic antibacterial organoarsenic compound salvarsan, now called arsphenamine.
In 1908, Ehrlich received the Nobel Prize in Physiology or Medicine for his contributions to immunology.
The Hoechst company began to market the compound toward the end of 1910 under the name Salvarsan, now known as arsphenamine. The drug was used to treat syphilis in the first half of the 20th century.
In 1910 Ehrlich and Hata announced their discovery, which they called drug "606", at the Congress for Internal Medicine at Wiesbaden.
Hata was nominated for the Nobel Prize in Chemistry in 1911 and for the Nobel Prize in Physiology or Medicine in 1912 and 1913.
In 1928, Sir Alexander Fleming postulated the existence of penicillin, a molecule produced by certain molds that kills or stops the growth of certain kinds of bacteria.
The first sulfonamide and the first systemically active antibacterial drug, Prontosil, was developed by a research team led by Gerhard Domagk in 1932 or 1933 at the Bayer Laboratories of the IG Farben conglomerate in Germany,
In 1939, coinciding with the start of World War II, Dubos had reported the discovery of the first naturally derived antibiotic, tyrothricin, a compound of 20% gramicidin and 80% tyrocidine, from B. brevis. It was one of the first commercially manufactured antibiotics and was very effective in treating wounds and ulcers during World War II.
Domagk received the 1939 Nobel Prize in Physiology or Medicine for Developing Prontosil
Ernst Chain, Howard Florey and Edward Abraham succeeded in purifying the first penicillin, penicillin G, in 1942, but it did not become widely available outside the Allied military before 1945.
The chemical structure of penicillin was first proposed by Abraham in 1942 and then later confirmed by Dorothy Crowfoot Hodgkin in 1945.
The term antibiotic was first used in 1942 by Selman Waksman and his collaborators in journal articles to describe any substance produced by a microorganism that is antagonistic to the growth of other microorganisms in high dilution.
For their successful development of penicillin, which Fleming had accidentally discovered but could not develop himself, as a therapeutic drug, Chain and Florey shared the 1945 Nobel Prize in Medicine with Fleming.