World Super Scientist’s – Alexander Fleming

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Serendipitous discovery in Medicine – Alexander Fleming

Sir Alexander Fleming  Scientist (1881-1955), Scottish bacteriologist discovered penicillin, the wonder drug against infections in those days.

At the age of 47 in the year 1928 he began working on staphylococcus, the bacterium responsible for causing boils, pimples and other sores. In bacteriology parlance, the word ‘culture’ indicates the nutritious substance, i.e., the meal or food for the microorganisms.

There are various culture media suitable for the growth of various microorganisms. The growing groups of microorganisms are called colonies. They are usually grown on petri dishes.

Experiments were conducted by Alexander Fleming Scientist in the laboratory of St. Mary’s Medical School and Hospital in London. He had filled some petri dishes with the germ staphylococcus, in the pursuit of his antibacterial experiments.

To his surprise, Alexander Fleming Scientist found that the bacteria failed to grow in one dish and he noticed that some light blue or grey coloured bits resembling the flecks of fungus over stale bread, were present in that dish.

Alexander Fleming Scientist surmised that this was due to contamination by a gush of wind or air which swept  the dish at the start of the experiment. Though this was a chance finding, it led to the definition of an antibiotic.

An antibiotic is a chemical substance produced by a micro organism which is inimical to other microorganisms. Hence an antibiotic has an antibacterial property or action.
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Alexander Fleming Scientist noticed that wherever the fungus had grown, the micro­organisms had died. The fungus was ‘penicillium’, a rare fungus in the mould family, species of a plant, Penicillium notatum. The fungus is present in the air. The fluid obtained from the penicillium fungus was named penicillin.

By then, Louis Pasteur had already proclaimed that germs cause diseases. Joseph Lister had discovered the antiseptic – carbolic acid, to kill germs.

But this has a limitation in that it can be used only topically, i.e., for administration on the surface of the body. Penicillin enters into the deeper tissues and organs, and so can be used systemically, e.g. intramuscular injection.

Penicillin is useful to combat septicemia, i.e., blood-poisoning by germs; this substance kills the germs without killing the white blood corpuscles, the soldiers in action during an infection.

Penicillin kills germs that cause pneumonia, influenza, diphtheria, meningitis, etc., It is the sheet anchor of treatment for venereal diseases (sexually transmitted diseases) even in the present day.

In 1937 two chemists. Howard Florey and E.B. Chain purified penicillin to make it safer for administration. The Nobel Prize for Medicine was awarded jointly to Fleming, Florey and Chain in the year 1945.

Alexander Fleming Scientist died on March 11, 1955 in London. Fleming’s fame is as immortal as a flame.

Yet, wherever there are roses there are thorns. Notwithstanding the rosy picture of benefit, administration of penicillin is fatal in some cases who are allergic to it. Extreme caution is required in the administration of this drug in those who are sensitive / hostile to this.


The identification of penicillium mold by Dr. Alexander Fleming in 1928 is hailed as one of the best-known anecdotes of medical discovery, not only because of its serendipity, but also because of its rank in the therapeutic armamentarium.

Humour in Medicine

Alexander Fleming Scientist discovered penicillin over the disc. Hence disc-over = disc+over.

Another serendipity in Medicine

Aspirin was discovered in 1897 by a German chemist, Felix Hoffman at Bayer, a milestone in Medicine.

Acetyl salicylic acid or aspirin :  ‘a’ stands for acetyl and ‘spir’ stands for the spiraea plant, meadowsweet (spiraea ulmaria), the source of salicin.
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