''Penicillium glaucum'' is a

mold A mold () or mould () is one of the structures that certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal ...

that is used in the making of some types of

blue cheese Blue cheese is any cheese made with the addition of Microbial food cultures, cultures of edible Mold (fungus), molds, which create blue-green spots or veins through the cheese. Blue cheeses vary in flavor from mild to strong and from slightly ...

, including Bleu de Gex, Rochebaron, and some varieties of

Bleu d'Auvergne Bleu d'Auvergne () is a French blue cheese, named for its place of origin in the Auvergne (province), Auvergne region of south-central France. It is made from cow's milk, and is one of the cheeses granted the Appellation d'origine contrôlée fr ...

and

Gorgonzola Gorgonzola (, ) is a famously pungent Italian blue cheese made from unskimmed cow's milk; believed to have been created in the 9th century; now with use of its name controlled under the criteria of a Protected Designation of Origin (PDO). Gorg ...

. (Other blue cheeses, including Bleu de Bresse, Brebiblu,

Cambozola Cambozola is a soft-ripened cheese specialty which is made of cow's milk. The blue cheese veins inside give this creamy cheese its very special flavor. History Cambozola was patented and industrially produced for the global market by the G ...

, Cashel Blue, Danish blue, Fourme d'Ambert, Fourme de Montbrison, Lanark Blue,

Roquefort Roquefort () is a sheep milk blue cheese from southern France. Though similar cheeses are produced elsewhere, European Union law, EU law dictates that only those cheeses aged in the natural Combalou caves of Roquefort-sur-Soulzon may bear the na ...

, Shropshire Blue, and Stilton use ''

Penicillium roqueforti ''Penicillium roqueforti'' is a common saprotrophic fungus in the genus ''Penicillium''. Widespread in nature, it can be isolated from soil, decaying organic matter, and plants. The major industrial use of this fungus is the production of blu ...

''.) In 1874, Sir William Roberts, a physician from

Manchester Manchester () is a city and the metropolitan borough of Greater Manchester, England. It had an estimated population of in . Greater Manchester is the third-most populous metropolitan area in the United Kingdom, with a population of 2.92&nbs ...

, noted that cultures of the mold did not display bacterial contamination.

Louis Pasteur Louis Pasteur (, ; 27 December 1822 – 28 September 1895) was a French chemist, pharmacist, and microbiologist renowned for his discoveries of the principles of vaccination, Fermentation, microbial fermentation, and pasteurization, the la ...

would build on this discovery, noting that ''

Bacillus anthracis ''Bacillus anthracis'' is a gram-positive and rod-shaped bacterium that causes anthrax, a deadly disease to livestock and, occasionally, to humans. It is the only permanent (obligate) pathogen within the genus ''Bacillus''. Its infection is a ty ...

'' would not grow in the presence of the related mold '' Penicillium notatum''. Its antibiotic powers were independently discovered and tested on animals by French physician Ernest Duchesne,Duchesne 1897
Antagonism between molds and bacteria. An English translation by Michael Witty. Fort Myers, 2013. ASIN B00E0KRZ0E and B00DZVXPIK. but his thesis in 1897 was ignored by the

Pasteur Institute The Pasteur Institute (, ) is a French non-profit private foundation dedicated to the study of biology, micro-organisms, diseases, and vaccines. It is named after Louis Pasteur, who invented pasteurization and vaccines for anthrax and rabies. Th ...

. ''P. glaucum'' was found by Pasteur to feed on only one

enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...

tartaric acid Tartaric acid is a white, crystalline organic acid that occurs naturally in many fruits, most notably in grapes but also in tamarinds, bananas, avocados, and citrus. Its salt (chemistry), salt, potassium bitartrate, commonly known as cream of ta ...

, L-(+)-tartaric acid, which makes its use the earliest example of

kinetic resolution In organic chemistry, kinetic resolution is a means of differentiating two enantiomers in a racemic mixture. In kinetic resolution, two enantiomers react with different reaction rates in a chemical reaction with a chiral catalyst or reagent, re ...

References

glaucum Molds used in food production Taxa named by Johann Heinrich Friedrich Link Fungus species {{Eurotiomycetes-stub