PHOSPHORUS FROM CASEINOGEN. 



455 



clearly that, except for quite a small residue, the whole of the phos- 

 phorus of caseinogen goes into solution in 24 hours. The residue 

 in the trypsin-caseinogen digestion is thus partly derived from the 

 caseinogen. 



In two other experiments we also determined the rate at which 

 soluble nitrogen was produced by 1 per cent, caustic soda, at the 

 same time making determinations of the soluble P 2 O 5 . The results are 

 best seen from the data and the accompanying curve (Exp. 5) : 



(4) 20 grs. caseinogen in 750 c.c. H 2 

 + 10 c.c. J NaOH. 250 c. c. * NaOH. 



(5) 20 grs. caseinogen in 750 c.c. H 2 

 + 10 c.c. y NaOH. 250 c.c. y NaOH. 



Soluble N. 

 in grs. 



0-0168-i-5 = 



0-0175 = 



0-0189 = 



0-0203 = 



0-0252 = 



0-0245 = 

 0-0245 



0-0280 = 

 0-0280 



3-36 



= 3-5 



= 3-8 



= 4-0 



= 5-0 



= 4-9 



- 4-9 



= 5-6 



= 5-6 



0-1449 =28-98 



Contrary to expectation the soluble nitrogen scarcely increased in 

 24 hours whereas the soluble P 2 O 5 in, this time reached a maximum. 

 It seems as if the 1 per cent, alkali had the special effect of only 

 splitting off soluble P 2 O S from caseinogen. 



During the action of the 1 per cent, caustic soda it was noticed 

 that the digest became distinctly opalescent. On exact neutralisation 

 with the calculated quantity of sulphuric acid there was no change, but 

 on slightly acidifying (not sufficient to turn congo red paper blue) a 

 voluminous precipitate was thrown down and the solution became almost 

 free from opalescence. We have made a few preliminary experiments 

 upon this precipitate, and have obtained a small quantity as a white dry 

 powder by redissolving in alkali and reprecipitating and then drying with 

 alcohol and ether. Its composition is under investigation. The acid 

 solution, which remained, contained albumoses precipitable by half 

 saturation and complete saturation with ammonium sulphate. 



PH. XXXIII. 30 



