52 THE VITAMINES 



split by acids, and likewise not in yeast ash. The experiments by 

 Wildiers were then confirmed by Amand (114) who demonstrated 

 that the failure of the yeast to grow, with just a slight inoculation, 

 was not due to the toxicity of the nutritive solution. Devloo (115) 

 reported that he isolated pure bios from lecithin. From his own 

 data it is evident that his preparation was not very active, and at 

 present we can say with certainty that the activity noted was due 

 to the contamination of the lecithin with vitamine. In this connec- 

 tion, it has been also stated that lecithin is curative for beriberi ; we 

 shall have occasion to refer to this matter later. 



We should not think that the important conclusions of Wildiers 

 found immediate acceptance in the literature. For example, H. H. 

 Pringsheim (116) took the stand that the bios of Wildiers was nothing 

 else than protein material, which was best used in the form that is 

 found in yeast cells themselves. This statement of Pringsheim's 

 was introduced into the literature, and therefore the conclusions of 

 Wildiers were given no further attention. For instance, Rubner 

 (117) said that the growth of yeast began only when there was a 

 certain relationship between the amount of food and the number of 

 yeast cells, an excess of food acting as a stimulus for yeast growth. 

 From time to time, however, reports appear in the literature dealing 

 with the observation of Wildiers. Vlahuta (118) prepared a peptone 

 from beer yeast, with cold suffuric acid, which could give rise to 

 fermentation. Kurono (119) foihid that a vitamine extract, prepared 

 from rice polishings, added to Hayduck or Nageli solution, accelerated 

 to a greater extent the growth of yeast cells and also the degree of 

 fermentation, than when peptone or asparagine were added. Brill 

 and Thurlow (120), on the contrary, could obtain no increase in the 

 growth of yeast cells with rice polishings. The ability of certain 

 brewery residues to accelerate fermentation can be attributed to the 

 presence of vitamines. Moufang (121) made the observation that 

 dead beer or baker's yeast exerted a marked catalytic action on 

 fermentation. Saito (122) was of the opinion that certain chemical 

 substances were important to allow of a complete development of the 

 reproductive capacity of yeast. Bokorny (123) observed an increase 

 in weight of yeast when it was grown on urine containing sugar 

 (we sliall see later that urine contains vitamine). Vansteenberge 

 (124) studied the influence of autolyzed yeast upon the growth of 

 yeast and lactic acid bacteria, and found that above a certain 



