22 DYNAMICS OF LIVING MATTER 



the case of the alcoholic fermentation. Buchner * showed that Pasteur f 

 was mistaken, and that the only difference was a technical one, inasmuch 

 as it requires a greater pressure to force the zymase out of the yeast 

 cell than other enzymes, e.g. invertase. Through the discovery of 

 Buchner, Biology was relieved of another fragment of mysticism. The 

 splitting up of sugar into CO 2 and alcohol is no more the effect of a 

 "vital principle" than the splitting up of cane sugar by invertase. The 

 history of this problem is instructive, as it warns us against considering 

 problems as beyond our reach because they have not yet found their 

 solution. The enzyme for the alcoholic fermentation of sugar is not 

 confined to yeast, but seems to occur more generally. Thus Pasteur 

 had already mentioned that certain kinds of fruit in the absence of air 

 produced alcohol besides CO 2 ; it is possible, however, that in fruits 

 alcohol forms only an intermediary product which is oxidized further, 

 or undergoes further changes, in the presence of oxygen, while it remains 

 unaltered in the absence of oxygen. Godlewski and Polzeniusz demon- 

 strated an alcoholic fermentation in seeds of plants which germinated 

 in the absence of oxygen. J The fact that in these cases the alcoholic 

 fermentation occurs only in the absence of oxygen seems to favor Pas- 

 teur's statement, that lack of oxygen increases the velocity of the fermen- 

 tative action of yeast in the case of alcoholic fermentation. 



Stoklasa and his pupils showed that in a number of plants and 

 germinating seeds CO 2 and alcohol are formed in the absence of oxygen 

 in the same proportion in which these substances appear in the alcoholic 

 fermentation of sugar, and that just as much dry substance from the 

 plants disappeared as corresponded to the sugar that was fermented. 

 They succeeded in extracting from these plants (roots of sugar beets, 

 potatoes, seeds of peas, seedlings of barley) an enzyme which acted 

 like Buchner's zymase. 



As far as animals are concerned, G. von Liebig had already shown 

 that the muscles continue to produce CO 2 in the absence of air, and 

 that the production of CO 2 is increased when the muscle becomes 

 active. Hermann repeated these experiments, and made sure that the 

 muscle continues to produce CO 2 , even if it does not contain any free 

 oxygen which can be extracted in the vacuum. Inasmuch as glycogen 

 disappears during activity, it looks as if the CO 2 formed in the absence 



* E. Buchner, H. Buchner, und M. Hahn, Die Zvmaseivirkung, Munchen und Berlin, 

 1903. 



t Pasteur, Etudes sur la biere, Paris, 1876. Annales de chimie et de physique, Vol. 58, 

 p. 323, i860. See also Liebig, Ueber Gahrung, uber Quelle der Muskelkraft und Ern'dh- 

 rung, Leipzig und Heidelberg, 1870. 



t Godlewski et Polzeniusz, Btdletin de rAcad. de Cracovie, 1901. 



Stoklasa, Hofmeister 's Beitrage zur chemischen Physiologie, Vol. 3, p. 460, 1902. 

 Pfluger's Archiv, Vol. 101, p. 311, 1904. 



