Antibiotics

• Medicines produced by living organisms which kill or stop the growth of the other disease-causing microorganisms are called antibiotics.

Discovery of antibiotics:

• Alexander Fleming discovered the first antibiotic called penicillin in 1929.
• He was culturing bacteria in his lab and suddenly found spores of green mould in one of his cultured plate. These spores of fungus inhibited the growth of bacteria and also killed some of the bacteria in that plate.
• He continued to observe this and later discovered a substance produced by this green mould which inhibits the growth of these bacteria.
• He called that substance as penicillin as it is produced by the fungi known as Penicillium notadum.
• Then similar substances were discovered and named as antibiotics.
• The sources of these medicines are microorganisms.
• They are produced by living organisms which do not harm themselves but are very toxic for other certain organisms.
• Thus they either inhibit their growth or kills them.
• The first antibiotic to be discovered was penicillin whose source is Fungi- penicillium.
• Other antibiotics like streptomycin and tetracycline are produced by bacteria streptomyces.