and Casein Peptone. 103 



of its aqueous solution with ammonium sulphate, and like peptone A 

 gave precipitates with nitric and acetic acid and with cupric sul- 

 phate. 



On analysis the following results were obtained : 



Casein antipeptone £. 



I. 0-3770 gram substance gave 0-2023 gram lrLfi = b-QQ per cent. 

 H and 0-6535 gram CO„=47-25 per cent. C. 



II. 0-2687 gram substance gave 0-1442 gram H„0=5-96 per cent. 

 H and 0-4667 gram 00^=47-36 per cent. C. 



III. 0-3732 gram substance gave 44-9 c. c. N at 14-4° C. and 757-0 

 mm pressures 14-31 per cent. N. 



IV. 0-3801 gram substance gave 46-0 c. c. N at 14-0° C. and 756-0 

 mm pressure =14 -3 8 per cent. N. 



V. 0-4760 gram substance gave 0-0374 gram ash=:7-86 per cent. 



VI. 0-5396 gram substance gave 0-0429 gram ash = 7-95 per cent. 



Percentage composition of ash-free substance. 



Average. 



C 51-35 51-42 51-38 



H 6-47 6-47 .... ..- 6-47 



N 15-54 15-61 15-57 



In a third digestion with trypsin, 2 kilos, of casein were warmed at 

 40° C. for five days with 3 litres of 0-5 per cent, sodium carbonate 

 containing an active trypsin solution, well thymolized. At the end of 

 the second day, considerable casein antialbumid separated from the 

 solution, this time more as a gummy precipitate than as a gelatinous 

 coagulum. On the sixth day, the alkaline fluid was filtered from 

 the small undigested residue, neutralized, concentrated, and the 

 caseoses precipitated by saturation with ammonium sulphate. In 

 this digestion, there was present only a very small trace of caseose 

 precipitable by saturation with salt, but considerable precipitable by 

 salt-saturated acetic acid. After repeated boiling of the ammonium 

 sulphate-saturated fluid, for complete removal of caseoses, the peptone 

 remaining was separated, purified and dried as already described. 

 The prodiict dried at 110° C. gave on analysis the following results. 



Casein antipepto7ie C. 



I. 0-3104 gram substance gave 0-1720 gram H„0 = 6-15 per cent. 

 H and 0*5252 gram CO., = 4614 per cent. C. 



II. 0-2756 gram substance gave 0-1513 gram H^O = 6-10 per cent. 

 II and 0-4638 gram CO, = 45 -89 per cent. C. 



