A Moldy Cantaloupe & The Dawn of Penicillin

By Rebecca Kreston | December 6, 2012 12:08 pm

For something that grows so carelessly and freely on our fruits and breads, mass producing the white mold and its hidden wonder drug penicillin was devilishly difficult. After Alexander Fleming’s accidental discovery of a bacteria-killing mold contaminating his cultures of Staphylococcus aureus, it languished as a laboratory parlor trick until World War II and the desperate need for treatments to fight bacterial infections became quickly apparent (1).


An image of Alexander Fleming’s original culture of penicillium mold. In his 1929 paper, it is described as a “photograph of a culture-plate showing the dissolution of staphylococcal colonies”. Image: A Fleming. Click for source.

Researchers working at Oxford University in the late 1930s had been able to isolate the penicillin compound and prove demonstrably that it could be used to treat deadly infections but the matter of transforming the spores from kitchen pests to medicinal powerhouses still remained. In 1941, struggling under the relentless blitz of their cities and factories, Britain turned to the United States to develop methods of the industrial manufacturing of penicillin (2).

It would be another fluke – the discovery of a moldy cantaloupe – that would yield a particular strain of mold that could produce prodigious amounts of this “magic bullet” antibiotic. Factories with the expert know-how on man-handling yeast and fungi into yielding their strange fruits  – alcohol distilleries and mushroom factories – were then tasked with the production of penicillin (2). Watch the video below to catch a glimpse of the very beginnings of what would ultimately become a behemoth pharmaceutical industry.

I love this video and all of its unspoken implications. The manufacturing of mankind’s very first antibiotic. The dynamism of an industry on the verge of changing death itself. Women in lab coats, Rosie the Riveter lab gals, toiling away in the molasses and mushroom factories to stop their young men from dying from sepsis (and to help cure those pesky gonorrhea infections!). Watching this video and swayed by the brimming optimism of its narrator, I thought, “By golly, with penicillin we CAN win this war!” And we did – penicillin radically changed the outlook of the war for the Allies, while Germany’s pharmaceutical companies scrambled, frantically trying to find the one strain of mold that would produce penicillin in its required quantities.

We won the war against the fascists but we’ve largely lost the war on microbes. This video will make you fall in love with the once mighty power of antibiotics but our Pyrrhic victory has now brought the battle to hospitals and antibiotic-resistant bacteria have turned against us again. Penicillin is now only effective for a chump change of bacteria and we are swiftly running out of our very best options. Enjoy this video and reflect on our short-lived golden age of antibiotics.


You can read Alexander Fleming’s paper on his oddball discovery, “On the Antibacterial Action of Cultures of a Penicillium, with Special Reference to their Use in the Isolation of B. influenzæ” published in 1929 in the British Journal of Experimental Pathology, here.

Absolutely fantastic: Fleming’s “germ paintings” using pigmented bacteria.

An ancient Sudanese tribe may have been guzzling penicillin in their beer, the antibiotic a by-product of the fermentation process. Sign this girl up!

Kulturkampf: The German Quest for Penicillin details the history of Germany’s efforts to steal/secure Fleming’s strain of mold and the penicillin arms race with the US and Britain.


(1) A Fleming (1929) On the Antibacterial Action of Cultures of a Penicillium, with Special Reference to their Use in the Isolation of B. influenzæ. Br J Exp Pathol; 10(3): 226–236

(2) J Stafford (December 4, 1943) More Penicillin Coming. Science News-Letters. 44(23): 362-4

&NA;, . (1930). Antibacterial Action in Cultures of Penicillium, With Special Reference to Their Use in Isolation of Bacillus Influenzas The American Journal of the Medical Sciences, 180 (3) DOI: 10.1097/00000441-193009000-00056


Body Horrors

Body Horrors looks at the history, anthropology and geography of infectious diseases and parasites.

About Rebecca Kreston

Rebecca Kreston is an infectious disease scholar trained in microbiology and epidemiology. She obtained her Biology degree from Reed College and her Masters of Science in Tropical Medicine from Tulane University. She's lived in tropical jungles, beaches and deserts around the world and has been exposed to several of the diseases that she studies. She currently lives in New Orleans, is a fourth year medical student and regularly battles insects of the Diptera, Siphonaptera and Hymenoptera orders.

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