Zymase (also known as alcoholase) is an obsolete term[1] for an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide.
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.
British chemist Sir Arthur Harden divided zymase into two varieties (dialyzable and nondialyzable) in 1905.
Some science historians[10] suggest that Eduard Buchner, in his 1897 work, merely repeated experiments already made by Antoine Béchamp in 1857.