On the Poisonous Action of Potassium 

 Persulphate on Plants, 



BY 

 S. Sawa. 



The salts of persulphuric acid exert a moderate oxidizing' 

 action on certain compounds. Thus Morrell and Crofts observed 

 a slow action on glucose in the presence of ferrous sulphate 

 whereby glucoson is produced. 1 Hitgounencq observed an 

 oxidation of uric acid, haematin, and bilirubin by these 

 salts; 2 uric acid in alkaline solution yields thus allanturic acid. 

 Pro seller found that while methyl green is quickly oxidized, 

 other color bases are not attacked as e.g. methylen blue. He 

 further observed that apomorphine is oxidized by it. The 

 oxidizing character of these salts makes it very probable that 

 they may act poisonously also on living cells in a way similar 

 to the action of hydrogen peioxid. Indeed it was observed by 

 Wackcr, 3 and further by Berard and Nicolas,^ and finally by 

 FriedloLnder y' that these salts easily kill bacteria. The last 

 named author states that \% sodium persulphate in aqueous 

 solution prevents the growth of pathogenic bacteria, and a 

 solution kills them ; and further that one gram of sodium 

 persulphate suffices to kill a rabbit of 2 kilo weight. Nicolas* 

 observed that an intraveinous injection of 0.04 gram of sodium 

 persulphate per kilo body weight kills a rabbit ; and per os 0.3 

 gram per kilo, a guinea pig. Loeiv observed that infusoria died 

 in a 0.$% solution of the potassium persulphate in about thirty 

 minutes. I thought it of some interest to extend such observa- 

 tions also to chlorophyll-bearing plants. 



1 Journ. Chem. Soc. 77, 1219. (1900). 



J Chem. News, 190 1. 



s Merck's Report 1894, 35. 



* Semaine Medicale 1S99, No. 43, p. 342. 



8 Therep. Monatschefte 1899, Feb. 



e La Semaine M<5dicale, Vol. 20 (1900). 



