A Text-book of physiological chemistry / Olof Hammarsten.

  • Olof Hammarsten
Date:
1908
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Licence: Public Domain Mark

Credit: A Text-book of physiological chemistry / Olof Hammarsten. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    Alcoholic fermentation and other processes of fermentation and putre^ faction are dependent upon the presence of living organisms, ferment fmigi, and splitting fungi of different kinds. The ordinary view, according to the researches of Pasteur, is that these processes are to be considered as phases of the life of these organisms. The name organized ferments or fer- ments has been given to such micro-organisms, of which ordinary yeast is an example. However, the same name has also been given to certain bodies or mixtures of bodies of unknown organic origin which are products of the <:• hemical work within the cell, and which after they are removed from the t'ell still have their characteristic action. Such bodies—for example, malt diastase, rennin, and the digestive ferments—are capable in the very small- est quantity of causing a decomposition or cleavage in very considerable quantities of other substances, without entering into permanent chemical combination with the decomposed body or with any of the cleavage or decomposition products. These formless or unorganized ferments are generally called enzymes, according to KtJHXE. A ferment in a more restricted sense is therefore a living being, while an enzyme is a product of chemical processes in the cell, a product which has an individuality even without the cell, and which may be active when ^separated from the cell. The splitting of invert-sugar into carbon dioxide and alcohol by fermentation is a fermentative process closely connected with the life of the yeast. The inversion of cane-sugar is, on the contrary, an enzymotic process caused by one of the bodies or a mixture of bodies formed by the living ferment, which can be severed from this ferment, and still remain active even after the death of the latter. Consequently fer- ments and enzymes are capable of manifesting a different behavior towards <'ertain chemical reagents. Thus there exist a number of substances, among which we may mention arsenious acid, phenol, toluene, salicylic acid, boracic acid, sodium fluoride, chloroform, ether, and protoplasmic poisons, which in certain concentration kill ferments, but which do not noticeably impair the action of the enzymes. The above view as to the difference between ferments and enzymes has lately been essentially shaken by the researches of E. Buchner i and his pupils. He has been able to obtain from beer-yeast, by grinding and strong pressure, a cell fluid rich in protein which when introduced into ' E. Buchner, Ber. d. devitsch. chem. Gesellsch., 30 and 31; E. Buchner and Rapp, xbid., 31, 32, 34; H. Buchner, Sitzungsber. d. Gesellsch. f. Morphol. u. Physiol, in Miinchen, 13, 1897, part 1, which also contains the discussion on this topic. See also E. and H. Buchner and M. Hahn, Die Zymasegarung, Miinchen, 1903; Stavenhagen, Ber. d. deutsch. chem. Gesellsch., 30; Albert and Buchner, ibid., 33; Buchner, ibid., 33; Albert, ihid., 33; Albert, Buchner, and Rapp, ibid., 35; in regard to the opposed views see Macfadyen, Morris, and Rowland, ibid., 33; Wroblewski, Centralbl. f. Physiol,, 13, and Joum. f. prakt. Chem. (N. F.), 64.
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