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{{Short description|Enzyme complex}}Zymase (also known as alcoholase) is an obsolete termBOOK, Cammack, Richard, Oxford dictionary of biochemistry and molecular biology, 2006, Oxford university press, 978-0-19-852917-0, 2nd, Oxford, viii, for an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide.The enzyme complex, composed of many different enzymes in yeast, catalyzes the breakdown of sugar into alcohol and carbon dioxide.”www.thefreedictionary.com/zymase{{Better source needed|date=February 2024}}JOURNAL,onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1905.tb02115.x, 10.1002/j.2050-0416.1905.tb02115.x, Zymase and Alcoholic Fermentation, 1905, Harden, Arthur, Journal of the Institute of Brewing, 11, 2–15, {{Obsolete source|reason=source is from 1905|date=February 2024}}WEB, biochemistry - Is Zymase, A Complex of Enzymes? Which ones?,biology.stackexchange.com/questions/10987/is-zymase-a-complex-of-enzymes-which-ones, 2021-05-29, Biology Stack Exchange, {{Better source needed|date=February 2024}}BOOK, Punekar, N.S.,link.springer.com/10.1007/978-981-13-0785-0, ENZYMES: Catalysis, Kinetics and Mechanisms, 2018, Springer Singapore, 978-981-13-0784-3, Singapore, 8, en, 10.1007/978-981-13-0785-0, It occurs naturally in yeasts.WEB, zymase,www.oxfordreference.com/view/10.1093/oi/authority.20110803133613699, 2021-05-29, Oxford Reference, en, Zymase activity varies among yeast strains.JOURNAL, Angelov, A. I., Karadjov, G. I., Roshkova, Z. G., 10.1016/0963-9969(96)00030-0, Strains selection of baker’s yeast with improved technological properties, Food Research International, 29, 3–4, 235, 1996, Zymase is also the brand name of the drug pancrelipase.WEB, Zymase Side Effects: Common, Severe, Long Term,www.drugs.com/sfx/zymase-side-effects.html, 2021-05-29, Drugs.com, en,

Cell-free fermentation experiment

Zymase was first isolated from the yeast cell in 1897 by a German chemist named Eduard Buchner who fermented sugar in the laboratory without living cells, leading to 1907 Nobel Prize in Chemistry.The experiment for which Buchner won the Nobel Prize consisted of producing a cell-free extract of yeast cells and showing that this “press juice” could ferment sugar. This dealt yet another blow to vitalism by showing that the presence of living yeast cells was not needed for fermentation.JOURNAL, Kohler, Robert E., 1972-09-01, The reception of Eduard Buchner’s discovery of cell-free fermentation,doi.org/10.1007/BF00346663, Journal of the History of Biology, en, 5, 2, 327–53, 10.1007/BF00346663, 11610124, 34944527, 1573-0387, The cell-free extract was produced by combining dry yeast cells, quartz and Diatomaceous earth and then pulverizing the yeast cells with a mortar and pestle. This mixture would then become moist as the yeast cells’ contents would come out of the cells. Once this step was done, the moist mixture would be put through a press and when this resulting “press juice” had glucose, fructose, or maltose added, carbon dioxide was seen to evolve, sometimes for days. Microscopic investigation revealed no living yeast cells in the extract.Buchner hypothesized that yeast cells secrete proteins into their environment in order to ferment sugars. It was later shown that fermentation occurs inside the yeast cells.British chemist Sir Arthur Harden divided zymase into two varieties (dialyzable and nondialyzable) in 1905.Some science historians“Our textbooks, however, erroneously tell us that Buchner was the first to extract an enzyme from yeast, and call it zymase, a ‘breakthrough’ that was achieved in 1897, some 35 years after Bechamp’s experiments!” (Milton Wainwright, Early history of microbiology”, Advances in applied microbiology, vol. 52, 2003, pp. 333–55, partly available on Google Books, esp. pp. 341–42.) suggest that Eduard Buchner, in his 1897 work, merely repeated experiments already made by Antoine Béchamp in 1857. This is not the case: what Buchner obtained with yeast zymase, and without yeast cells, was alcoholic fermentation, while Béchamp had explicitly stated that, in absence of yeast cells, and by use of what he, also, called “zymase”, he obtained only sugar inversion and no alcoholic fermentation.Antoine Béchamp, Les microzymas, Paris, 1883 (repr. Paris, 1990), pp. 286–88 According to K.L. Manchester,Keith L. Manchester : “Antoine Béchamp: père de la biologie. Oui ou non?”, Endeavour, Vol. 25, n° 2, 1 juny 2001, pp. 68–73; Keith L. Manchester : “Louis Pasteur, fermentation, and a rival”, South African Journal of Science, vol. 103 (2007), online. what Béchamp called “zymase” was invertase.

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