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25, 35 02 ) tnat a l anme heated alone, or, still better, with an excess 

 of concentrated phosphoric acid, to 220-230, is decomposed into 

 acetaldehyde, carbon monoxide and ammonia, a systematic search 

 for ferments whether inorganic or enzymic which can effect a ca- 

 talytic decomposition of alanine with production of acetaldehyde 

 seems desiderable. 



Schade found (Zeilsch. physikal Chem., 1906, I, 57) that dextrose 

 is decomposed by alkalis with the formation of acetaldehyde and 

 a formiate, whilst acetaldehyde and formic acid yield ethyl alcohol 

 and carbon dioxide under the influence of rhodium sponge. 



Schade thinks it is not improbable that yeast effects the conversion 

 of dextrose into ethyl alcohol and carbon dioxide in a somewhat si- 

 milar manner, dextrose decomposing into an intermediate product, 

 which in turn yields formic acid and acetaldehyde, an enzyme 

 functioning in a similar manner to rhodium sponge then coming 

 into play. P. B. Jensen supposes that zymase consists of two en- 

 zymes (Ber. Deut. bot. Ges., 1908, 26, A, 666) the first capable of 

 effecting the conversion of dextrose into dihydroxyacetone, the 

 second decomposing the latter into ethyl alcohol and carbon dioxide. 



Buchner and Meisenheimer consider Schade's view quite unten- 

 able (Ber., 1906, j>9, 4218; 1910, 43, 1782) but there seems to be 

 a consensus of opinion that some intermediate product, probably 

 of the formula CjH 6 O ? is produced, and that this gives rise to al- 

 cohol and carbon dioxide either directly or possibly with the in- 

 termediate formation of acetaldehyde and formic acid. 



From the experiments of Buchner and Meisenheimer it would 

 appear that any possibility of formic acid playing a part in ferment- 

 ation was out of the question, but, the authors' experiments show 

 that the amount of acetaldehyde formed is largely reduced when 

 a formiate is present, whilst the use of small quantities of formic 

 acid as an aid to good fermentations has been strongly advocated 

 by H. Lange (Zeitsch. filr Spiritusind., 1905, 28, 341). With refe- 

 rence to the possibility of formic acid playing a part in alcoholic 

 fermentation, attention may be drawn to F. Ehrlich's views on the 

 decomposition of leucine and the occurrence of valeraldehyde as 

 a by-product (Ber., 1907, 40, 1046). 



The authors conclude that it seems not improbable that some 

 substance, possibly alanine, which should ferment normally to give 

 ethyl alcohol and carbon dioxide, may be formed either as a pro- 

 duct of the decomposition of the dextrose or perhaps as a trasform- 

 ation product of dihydroxyacetone in presence of nitrogenous ma- 

 terial. 



