82 COLLOID CHEMISTRY OF THE PROTEINS 



a similar way the degree of hydrolysis with increasing addition 

 of acid can be read off within OA, as the corresponding quantity 



of ac id which remains 

 free is included in the 

 area OBC. Further, 

 the course of the curve 

 OB shows that the 

 degree of hydrolysis 

 steadily increases up to 

 the value of the com- 

 bined acid represented 



0-01 



an on < by AB Beyond that 



FIG. I9 .-Hydrolysis of acid albumin. ^ ^ excess Q{ add 



rapidly increases, and the hydrolysis is suppressed, as is easily 

 seen by the form of the area BCD. At D the hydrolysis of the 

 protein salt is practically nil. The tabular statement which 

 follows, giving in the usual way the mean hydrolysis of the 

 serum albumin used with increasing acid concentration, demon- 

 strates the same variation. 



Table 34. 



Our observations, therefore, support the view that the com- 

 bination with acid increases proportionally with the content 

 of albumin. The value of maximum combination of 2-1 X 

 io- 2 N HC1 per litre for 1-26 per cent albumin gives for a con- 

 centration of I per cent, albumin the value i -66 X io- 2 NHCl. 

 K. Manabe and J. Matula * obtained as a maximum value 1-8 

 X io- 2 N. acid for a 1-09 per cent, solution of serum albumin, 

 which is equal to 1-65 X io- 2 N HC1 for a i per cent, solution. 

 * Biochem. Zeitsch., 1913, 52, 385. 



