Alcoholic fermentation / by Arthur Harden.

  • Arthur Harden
Date:
1932
Catalogue details

Licence: In copyright

Credit: Alcoholic fermentation / by Arthur Harden. Source: Wellcome Collection.

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    have shown that calcium pyruvate, accompanied by some calcium lactate [Fernbach and Schoen, 1923], is formed when certain yeasts (a “ mycolevure ” and a Champagne yeast) are grown in a synthetic medium in presence of calcium carbonate. On the other hand, Kerb [1919], and Kerb and Zeckendorf [1921], who have been confirmed by von Grab [1921], and by Klein and Fuchs [1929], find that the acid is not produced by culture yeasts in this way. Rapid fermentation of considerable amounts of sugar by pressed yeast in presence of calcium carbonate also yielded no pyruvic acid [Kostytschev and Frey, 1925], whereas acetic, malic, and succinic acids were all formed. By employing a “ fixing ” agent (see p. 128), v. Grab [1921] has also succeeded in demonstrating the production of pyruvic acid as an intermediate stage in the alcoholic fermentation of sugar by yeast- juice. The reaction employed was the condensation of pyruvic acid with /3-naphthylamine to form &-methyl-/3-naphthocinchoninic acid (Dobner) : CH3 • C : Nx 2CH3 . CO • COOH + H2N • C10H7 - 2H20 + C02 + H2 + | \c10h6 HC : C • COOH. The experiment was carried out by adding the naphthylamine in ethereal solution and shaking the mixture until all the sugar had been fermented, the condensation product being then isolated by extraction of the evaporated mass with alcoholic ammonia. 18 g. of sucrose when fermented by 1620 c.c. yeast-juice in presence of 3*6 g. /3-naphthylamine in 75 c.c. ether yielded in all 0-63 g. of pure condensation product, and a larger scale experiment with 180 g. sucrose gave a yield of 7-3 g. The demonstration of the formation of pyruvic acid by the aid of other fixation agents such as brucine [Traetta-Mosca, 1926, 1927] and semicarbazide [Kostytschev and Soldatenkov, 1928] has been reported, but in each case the claim has been subjected to severe criticism [Rimini, 1926; Neuberg and Kobel, 1927, 3; Lebedev, 1928; Klein and Fuchs, 1929, where the literature is fully cited]. Demonstration of the Intermediate Formation of Methylglyoxal and Pyruvic Acid. A more satisfactory result has been obtained [Neuberg and Kobel, 1928, 1 ; 1929, 3 ; 1930, 1, 2 ; Bayo, 1929, 1, 2 ; Kobel and Scheuer, 1930] by the action of dried yeast on magnesium hexosediphosphate under particular conditions of volume of solution per unit weight of dried yeast. The effect of altering the volume of liquid employed is
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