x Qi2] CURRENT LITERATURE 



341 



the effects of Oidium lactis killed with acetone and ether on the lactic, succinic, 

 and mandelic acids. The results obtained do not conform with those obtained 

 in the foregoing experiments with P enicillium . Only lactic acid gave a greater 

 carbon dioxide production than the control with distilled water. With 

 mandelic and succinic acids the control flasks yielded greater amounts of 

 carbon dioxide. In an experiment in which the fungus was left in liquid air for 

 several hours, subsequent cultures showed that the cells had not all been killed. 



A similar set of experiments carried out by Herzog, Ripke, and Saladin 6 

 with acetone preparations of Mycoderma cerevisiae showed that with acetic acid 

 and lactic acid the carbon dioxide production was less in the acid medium than 

 in distilled water, although a part of the acid in each case had disappeared. The 

 carbon dioxide output in experiments with the different isomeric modifications 

 of mandelic and tartaric acids was not determined, but the whole added quan- 

 tity of these acids could not be recovered. In some cases with mandelic acid 

 the total acid content of the controls at the end of the experiment was as great as 

 that in flasks to which acid had been added. The authors assume that the 

 autolytic production of acid by the killed fungus cells reaches a certain maxi- 

 mum. If that maximum has been attained by the addition of a foreign acid, 

 no further spontaneous acid formation occurs. Succinic acid depressed the 

 production of carbon dioxide, but there was no evidence that any of the acid 

 had disappeared. The general conclusion from this last set of experiments is 

 that the production of carbon dioxide by killed cells of Mycoderma is depressed 

 in acid media, although the quantity of acid is diminished. The disappearance 

 ot the acid, therefore, cannot be explained as a process of oxidation, nor is the 

 process one of metabolism, since the cells were dead. In view of the compara- 

 tively small quantities of acids which disappeared apparently through the action 

 of the killed fungus cells, the experiments would have been more convincing 

 it the authors had reported control experiments showing how much of the acids 

 could be immediately recovered from the mixtures. 



In another paper by Herzog and Saladin 7 the effect of leucine on the 

 carbon dioxide production of P enicillium is reported. The method of experi- 

 mentation was similar to that described above in the experiments of Herzog 

 and Meier, and the results were comparable to those obtained with oxyacids. 

 The addition of leucine was followed by an increased production of carbon 

 dioxide, which was greater than that calculated on the assumption that all the 

 available leucine had been oxidized to carbon dioxide and water. 



The important series of researches of Ehrlich 8 on the behavior of amino- 



Herzog, R. O., Ripke, O., und Saladin, O. Ibid. 73=290-301. 1911. 

 'Herzog, R. O., und Saladin, O., Ueber das Verhaiten einiger Pilze gegen 



Aminosauren. Ibid. 73:302-307. 1911. 



X 



Ehrlich 



organge pflanzlichen Erweissstoffwechsets und ihre Bedeutung fur die Alkoholische 



Garung und andere pflanzenphysiologische Processe. Landwirth. Jahrb. 38: 289-327, 

 1909. 



