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Episode Transcript

Speaker 1 (00:00):
The forgotten inventor of antibiotics. Sixteen years before Alexander Fleming
discovered the bacteria inhibiting properties of mold, a French scientist
had described a similar discovery in his doctoral thesis. In
eighteen ninety seven, a young French medical student named Ernest
Duchen submitted a doctoral dissertation titled Contribution to the Study

(00:22):
of Vital Competition in Microorganisms Antagonism between molds and Bacteria.
In this thesis, Duchen proposed a revolutionary idea that bacteria
and molds are constantly engaged in a survival struggle, and
humans could harness this antagonism to treat diseases. According to
Amusing Planet, although the medicinal properties of molds and plants

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in treating infectious diseases had been known since ancient times,
Duchen was the first to experimentally demonstrate that certain molds
could destroy disease causing bacteria such as Salmonella typhi which
causes typhoid fever, and Escherichia coli in laboratory settings by
injecting them into guinea pigs. What Duchane discovered was natural penicillin,

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a breakthrough often associated with Scottish physician Alexander Fleming. Duchane's
work was almost forgotten until it was rediscovered more than
fifty years later in nineteen forty nine, four years after
Fleming was awarded the Nobel Prize. Ernest Duchane was born
in Paris in eighteen seventy four, the son of a
chemical engineer who owned a tanning factory. After finishing high school,

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he enrolled at the Leon Military Medical School e col
d Servis de Sante Militaire in eighteen ninety four. Two
years later, Duchin began researching under the guidance of Gabriel Roux,
a professor of microbiology and the director of the provincial
Sanitation office in Lyon. Rue observed an interesting phenomenon. Although

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mold spores were abundant in the air, they were absent
from tapwater and mountains, even though they could grow in
distilled water. This led Rue to suspect that some microorganisms
in water might inhibit mold growth. He suggested Duchen explore
this idea as the foundation for his thesis. This observation

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became the starting point for Duchen's core research on competition
between microorganisms, eventually leading to his discovery of penicillin. Duschen
conducted a series of experiments in which he cultured Penicillium
glaucum in meat broth and then introduced small amounts of
Salmonella typhi and Escherichia koli into the mold population. Each

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time the bacterial spores died. Duschen concluded that in the
struggle for survival, bacteria were initially more dominant. However, Duchen
speculated that before penicillium perished, it could weaken bacteria, thus
reducing their virulence and disease causing properties. To test this hypothesis,
Duchan injected guinea pigs with a solution containing equal amounts

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of Penicillium glalcum and E. Coli. At first, the animals
became seriously ill, but they recovered quickly. Two days after
the first injection, Dushane administered another dose. The guinea pigs
showed no signs of illness, indicating that they had developed
resistance to E. Coli. A similar immune response occurred when

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guinea pigs were injected with a mixture of S. Typhi
and P. Glalcum. Duschan observed that mold Penicillium glalcum, when
introduced into animals alongside certain bacteria such as S. Typhi
and E. Coli could significantly reduce their virulence. While Duchen
could not isolate the antibiotic substance produced by Penicillium glalcum,

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he correctly concluded that molds could be used to treat diseases.
Duchen's thesis earned him his doctorate, but his ideas did
not attract attention from the medical community. By the end
of eighteen ninety eight, Duchen was appointed as a doctor
in the second Cavalry Regiment, stationed in Sinless. He married
in nineteen oh one, but his wife died two years

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later from tuberculosis. He himself fell ill in nineteen oh
four and was discharged from the army in nineteen oh seven.
Duchen spent his final years in various sanatoriums in southern
France and Switzerland before passing away in nineteen twelve at
the age of thirty seven. In nineteen twenty eight, sixteen
years after Duschane's death, Alexander Fleming made a similar discovery

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when his petri dish of Staphylococcus oreus was accidentally contaminated
with penicillium mold. Like Duchesen, Fleming observed that the molds
secreted a compound that inhibited bacterial growth. Despite its significance,
Fleming's nineteen twenty nine paper, published in the British journal
Experimental Pathology, failed to attract much attention. Much like Duschane's

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thesis years earlier, Fleming himself was unsure of the practical
medical applications of his discovery. He focused more on its
potential use in isolating bacteria rather than treating infectious diseases.
His colleagues in chemistry attempted to isolate the active penicillin compound,
but were unsuccessful, leading Fleming to discontinue further research.