Antibiotics: A brief history-Part 2
During the nineteenth century, scientists were conducting experiments to find a powerful magic substance that would rid the world of all infection. In Paris in 1877, two scientists, Louis Pasteur and Robert Koch, “discovered” the actual process of antibiosis when they observed that a harmless, airborne bacillus could inhibit the growth of a harmful, disease causing bacillus. Pasteur also observed that injecting animals with harmless bacteria obtained from the soil could help prevent them from developing anthrax.
Modern research on antibiotic medications began in Germany in the early 1900s. In 1909, a German scientist named Paul Ehrlich isolated a drug called Salvarsan that proved effective in treating syphilis, a bacterial infection caused by a type of bacteria called a spirochete. Unfortunately, since Salvarsan was actually a dye used in the manufacture of clothing, it proved fairly toxic and its use was eventually discontinued.
The big breakthrough in the history of antibiotics came in 1928 when Alexander Fleming discovered penicillin. While conducting research on Staphylococcus bacteria, Fleming noticed that the bacteria was not growing very well on an agar plate that had been contaminated with mold. He identified this mold as Penicillium notatum. He then distilled a solution of this mold into a broth, named it penicillin, and injected it into some patients of his who were ill with a variety of infections. Many of them got better and the broth proved non-toxic. Unfortunately, he didn’t make very much of the penicillin liquid and when he presented his findings in a British scientific journal, his colleagues weren’t very impressed with his work.
In the late 1930s, two other scientists, Ernst Chain and Howard Florey came across Fleming’s work and realized its potential importance. They isolated and purified more penicillin and ran experiments on rats and mice to demonstrate its effectiveness. In one experiment, 50 mice were injected with lethal doses of Streptococci bacteria. 25 of these mice received multiple doses of penicillin, the others did not. After 10 days, 24 of the 25 mice who had received the antibiotic were still alive. All the mice who didn’t get the antibiotic were dead. The effectiveness of penicillin had been proven and all three scientists shared the Nobel Prize in Medicine in 1945.
British physicians from the Oxford group approached American chemical companies about manufacturing penicillin. Concurrently, two antibiotics were isolated from the soil. One of these, streptomycin, was used to treat tuberculosis for many years. Another, chloramphenicol, was used to treat a typhoid epidemic in Bolivia in the late 1940s. In the 1960s, further research launched the development of the second generation of antibiotics to be derived from penicillin. These second generation antibiotics proved to be very effective against strains of bacteria that had developed resistance to penicillin. Unfortunately, many bacteria are now resistant to these second generation antibiotics.
