On the Poisonous Action of the Hydroxyl-derivatives of Benzol 

 upon Yeast and Bacteria. 



BY 



K- Yabe, Nogakushi. 



The toxical action of phenol, of the dioxybenzols (resorcin, 

 pyrocatechin and hydrochinon) and of the trioxybenzols (phloro- 

 glucin,^ pyrogallol) has been compared in regard to animals but 

 not yet in regard to the lower fungi. As a general rule, it has 

 been found that the poisonous character increases with the 

 number of hydroxyl groups entering into the benzol ring. 

 Stolnikow observed that phloroglucin is more poisonous for frogs 

 than resorcin, and this is again more poisonous than phenol. 

 While the lethal dose of phenol for warm-blooded animals is 

 0,3-0,7 gr. per kg., 0,08 gr. resorcin is found to be sufficient 

 (Zeni and Betclli). The three isomeric dioxybenzols show a very 

 great difference in their toxical action. Pyrocatechin is strong- 

 est, then follows hydrochinon and finally resorcin. Of the trioxy- 

 benzols, phloroglucin is less poisonous than pyrogallol. Loew 2) 

 observed that in 1 per mille phenol solution some infusoria still 

 remained alive after 15 hours, and certain algae have been found 

 alive after three days, while pyrocatechin solution of the same 

 strength killed infusoria and diatoms after a few minutes, spiro- 

 gyra after several hours. Hydrochinon acts somewhat more 

 slowly, but in resorcin solution of that strength infusoria live 

 several hours, and algas are found alive even after 18 hours. 

 The phenol character is here evidently increased by the toxical 

 effect caused by the capability of absorbing oxygen. Pyrocatech- 

 in and hydrochinon will rob the cells of the dissolved molecular 

 oxygen much more quickly than phloroglucin, and consequently 

 we find with the former also a much more poisonous character. 



1) The third isomeride, oxyhydrochinon, has not yet been physiologically 

 studied. 



2) Natiirliches System der Giftwirkungen, p. 50-51. 



