Sir Alexander Fleming(1881-1955): the Penicillin

Alexander Flemming in his laboratory in 1943 (KPA)
Sometimes mere chance can reveal groundbreaking discoveries. Such was the case with penicillin, which Scottish chemist Alexander Fleming came across accidentally in 1928.
But thanks to Fleming's perseverance and sharp scientific faculties, the discovery was refined into the cornerstone of modern antibiotics.
And consequently, penicillin has changed the face of medicine forever.
When Alexander Fleming worked as a captain in the British Army's medical corps during WWI, infection was the main cause of death, turning even non-lethal wounds into life-threatening situations.
And while doctors where already using antiseptics for treating wounds, their effects would often backfire by working against the body's natural healing process.
Back at St Mary's hospital in London, Fleming researched tirelessly alongside the eminent bacteriologist Sir Almroth Wright.
The aim: finding an alternative to antiseptics. Fleming's interest in the antibiotic properties of moulds and fungi brought him to experiment with staphylococci - a particularly aggressive strain of bacteria that can cause infections as severe as meningitis - which he cultured in dishes at his laboratory.
Returning from a holiday, Fleming found some forgotten laboratory dishes on which a fungus had seemed to stunt bacterial growth.
Perplexed, Fleming isolated an extract from the mould and identified it as part of the penicillium family. He would name the substance penicillin.



Penicillium chrysogenum fungal culture (Dr Jeremy Burgess / Science Photo Library)
But there were more challenges ahead. While further experiments proved the antibacterial effects of the accidental discovery, Fleming found it very difficult to produce penicillin in large quantities
From 1929 to 1940, he laboured on - insecure about the final outcome - to find a way to mass produce penicillium mould. For twelve long years, Fleming cultivated the original strain of mould he had discovered and invited renowned chemists to have a go at refining it.
Finally, British chemist Ernest Chain devised a method of isolating and concentrating penicillin.
And in turn, his colleague Norman Heatley suggested transferring the active ingredient of penicillin back into water, which paved the way for producing penicillin as a commercial drug in 1945.
Seen from this perspective, the development of penicillin can be perceived as a team effort, crowned with the Nobel Prize for Medicine in 1945 for the three scientists.
But without Fleming's persistence in pursuing his accidental discovery, it may have taken an altogether different turn.
As Fleming himself would say: "It is the lone worker who makes the first advance in a subject; the details may be worked out by a team, but the prime idea is due to enterprise, thought, and perception of an individual."

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