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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    power either to Hagedorn and Jensen’s solution or to hypoiodite. The [a]gj61 of the barium salt in water is -f- 1320 (c — 3-2) ; that of the free acid is + 185° (c — 2*4). The phosphoric acid group is readily removed by the action of bone phosphatase leaving trehalose. Hydrolysis by acid yields glucose and phosphoric acid as final pro- ducts, but as the disaccharide linkage is more readily broken than the phosphoric, glucosemonophosphoric ester accumulates for a time in the products. Whether this is identical with the glucosemonophos- phoric ester which forms one constituent of the Robison hexose- monophosphoric ester is not yet known. The sodium salt of the trehalosephosphoric ester is readily fermented by dried yeast, more slowly by zymin and yeast-juice. The brucine salt crystallises with 9H20 in large clusters of needles. It is not known whether the formation of this ester bears any essential relation to the mechanism either of alcoholic fermentation or of glycogen formation. The Hexosemonophosphoric Ester of Muscle. Soon after the discovery of hexosediphosphate, attention was drawn by Embden and his colleagues [Embden, Griesbach, and Schmitz, 1915 ; ITagemann, 1915 ; Embden, Griesbach, and Laquer, 1915 ; see also Foster and Moyle, 1921] to the fact that the addition of this compound to the press juice from muscle, kidney, or uterus caused an increase in the amount of lactic acid and phosphoric acid formed, and Embden concluded that the normal precursor of lactic acid in muscle, which he termed lactacidogen was some substance closely connected with hexosediphosphate. Later hexosediphosphoric acid was actually pre- pared from muscle by a process in which sodium fluoride was added to the muscle press juice [Embden and Zimmermann, 1924], whereas a later preparation [Embden and Zimmermann, 1927] which was carried out without addition of fluoride led to the isolation of a hexose- monophosphoric ester closely corresponding with that obtained by fermentation (Robison ester). By this method no hexosediphos- phoric acid could be detected in the muscle pulp, and it is now recognised [see Pryde and Waters, 1929] that living muscle does not contain the diphosphate, but that this is formed in the press juice in the presence of fluoride. Embden’s lactacidogen, therefore, is a hex- osemonophosphoric ester and this, like the Robison ester which it closely resembles [see Lohmann, 1928, 1], is probably a mixture of an aldo- with a keto-ester, the former being present in large excess.
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