Diet and dietetics / by A. Gautier; edited and translated by A. J. Rice-Oxley.

  • Rice-Oxley A. J.
Date:
1906
Catalogue details

Licence: In copyright

Credit: Diet and dietetics / by A. Gautier; edited and translated by A. J. Rice-Oxley. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    MECHANISM OF ALIMENTATION Let us try to analyse it, as nearly as possible, in the compara- tively simple case which we have intentionally chosen. Placed in contact with sweetened liquor, the cell of beer yeast takes possession at once of all the nitrogen of the ammoniacal salts, the sulphur of the sulphates, the phosphorus of the phos- phates placed at its disposal. All these salts have nearly disap- peared right from the very beginning. From the sugar already existing in the nutritive liquor, it has borrowed its carbon as well as the oxygen which is necessary to it, for it lives in surroundings deprived of air. From the mass of these elements (although we are not able in the present state of our knowledge to indicate the sequence of the intermediary processes), it has formed most com- plex substances : these albuminoids, phosphorated proteids, the cel- lulose, glycogen, etc., which we find in the cells of new formation. The nutrition of the yeast, far from being an act of simple intussusception or of chemical deposition in the living cells of matter pre-existing in the primitive liquid as when a crystal, for example, grows in its mother water, has been then in reality an extremely complex act. The little organism has broken up the chemical substances offered to it; it has extracted from them the radicals, or the parts which are suitable to it, and has combined them in the form of substances which the vital action had caused to disappear, and from these materials, thus formed, it has nour- ished itself up to the point where, having reached its highest development, it has used these food stuffs to reproduce new cells capable of recommencing the same work. To nourish oneself, is then, in reality, to produce at the expense of the food, whatever it may be, a series of acts of dislocation, of simplification, and as a corollary and complement, of new associa- tions, from which results the reproduction of specific constituent principles which the vital action had destroyed. The cell of yeast adds a new act to this construction of complex and specific organic materials starting from different principles in the very simple case which we have chosen. With a little sugar and substances chemically inert, ammoniacal salts, phosphates, sulphates, etc., substances saturated with oxygen, it forms albumi- nous principles, fats, starch, glycogen, cellulose, etc., combustible matters filled with chemical potentiality. In order to succeed in thus changing inert material into combustible material, this organism required some source from which it could draw the energy contained in these products of new formation. Life can very well fashion matter but it can neither create it nor endow it with power. In the case under consideration, the yeast cell finds the source of energy indispensable to it in the destruction of the greater part of the alimentary sugar, transformed by it into carbonic acid and alcohol, a new system containing Jess chemical force than the sugar from which it comes. The difference
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