HYDROCARBON COMPOUNDS 79 



ported that S. membranaefaciens could take its carbon from ethyl but 

 not from methyl alcohol. Bokorny l studied the sources of carbon 

 for yeasts and stated that urea cannot supply carbon for yeasts. This 

 is confirmed by Lindner and Wiist 2 who found that urea could supply 

 nitrogen but not carbon. Pentoses were found by Bokorny to be not 

 fermented but could serve as a source for carbon. Others have shown 

 that different organic acids, glycerol, asparagin, peptone, etc., could 

 be used. Will 3 found that, in mineral media, esters could act as a 

 source of carbon. Lindner 4 studied the assimilability of the various 

 carbohydrates. He investigated dextrose, mannose, galactose, levulose, 

 trehalose, sucrose, maltose, lactose, melibiose, rafnnose, a-methyl- 

 glucoside, xylose and rhamnose. The simple sugars, trehalose, suc- 

 rose and maltose, were fermented. Lactose was not. In certain cases, 

 there was a questionable fermentation of xylose and rhamnose. Meli- 

 biose was not fermented by top yeast. There seemed to be a marked 

 difference in action toward a-methylglucoside. In a later paper 

 Lindner 5 again found maltose better than other sugars. 



Bokorny s has stated that external factors have great influence in 

 fermentation and assimilation studies. Light is not important for 

 the yeasts but plenty of air is important. The increase in dry sub- 

 stance in this experiment was taken as the criterion of assimilation. 

 Assimilation was promoted by free KOH at certain concentrations. 



Kita 7 found that purified maltose was less easily assimilated than 

 unpurified. He attributed this to the fact that in the impure maltose 

 there was an oryzanin-like compound. The same thing was observed 

 by Kluyver. 8 



1 Bokorny, T. The formation of protein from different sources of carbon. 

 Munch, med. Wochenschr. 63, 791-2; Chem. Absts. 11 (1917) 2813. 



2 Lindner, P. and Wiist, G. Wochenschr. Brau. 30, 477-9. Chem. Absts. 8 

 (1914) 727. 



3 Will, H. Influence of esters on yeasts and other budding fungi. Cent. 

 Bakt. Abt. II. 38, 539-76. Chem. Absts. 8 (1914) 357. 



4 Lindner, P. Assimilation of various carbohydrates by different yeasts and 

 the like. Wochenschr. Brau. 47, 561-563. Chem. Absts. 6 (1912) 1808. 



Lindner, P. and Saito, K. The assimilation of various carbohydrates by 

 different yeasts. Wochenschr. Brau. 27, 509-13; Chem. Absts. II, 476, 5 (1911) 

 1489. 



6 Lindner, P. The results obtained in fermentation and assimilation experi- 

 ments with yeasts. Chem. Ztg. 34, 1144. 



6 Bokorny, Th. Relation between sugar fermentations and sugar assimila- 

 tion. Allgem. Brau-Hopfen Ztg. 57, 447-80; Chem. Absts. 12 (1918) 847. 



7 Kita, G. The question of the assimilability of maltose by yeasts. Zeit. 

 Garungsphysiologie, 4, 231-4. Chem. Absts. 8 (1914) 3809. 



8 Kluyver, A. J. Assimilability of maltose by yeasts. Biochem. Z. 52, 486; 

 Chem. Absts 8 (1914) 359. 



