418 



Dr. A. Harden and Mr. W. J. Young. 



[Dec. 8, 



0*3 molar potassium phosphate solution were added and the liquid at once 

 heated to the boiling point, filtered, and the coagulate washed. 



C. The same additions were made as to B and the liquid then fermented 

 until the close of the initial period, after which it was heated and filtered 

 like the others. 



The total phosphorus was then estimated in each of the coagulates and in 

 •each of the filtrates, and the phosphorus precipitated by magnesium citrate 

 in each of the three filtrates. The estimations of total phosphorus were 

 made by heating with sulphuric and nitric acids until colourless, diluting and 

 precipitating with magnesium citrate mixture in presence of excess of 

 ammonia. 



The following were the results obtained, the numbers representing the 

 grammes of magnesium pyrophosphate per 25 c.c. of juice. 



Table VII. 





A. 



Original juice. 



B. 



J uice + phosphate. 

 Not fermented. 



C. 



Juice + phosphate. 

 Fermented. 



Coagulate 



Filtrate— 

 (a) Precipitated by 



(5) Not precipitated 

 by Hg citrate 



Total 



0-053 



0-126 

 0-271 



0-057 



0-480 

 0-282 



0-072 



0-070 

 0-679 



0-450 



-819 -821 



1 



The amount of phosphate added was equivalent to - 372 gramme of 

 magnesium pyrophosphate. 



A number of other results are given to show the extent to which 

 phosphate is converted into the non-precipitable form by this reaction. 

 All the estimations were made by boiling and filtering the fermented liquid 

 immediately upon the close of the initial period. As before the numbers 

 represent grammes of magnesium pyrophosphate obtained from 25 c.c. of 

 juice. 



The form in which this non-precipitable phosphorus is actually present in 

 the fermented liquid, and in the liquid which has been boiled and filtered, 

 has not yet been ascertained with certainty. Experiments which are still in 

 progress, however, appear to indicate that it exists in combination with 

 glucose, probably in the form of a phosphoric ester. 



