428 



K. G. DERNBY AND J, BLANC 



Pepton test 



Table 8 shows the composition of the pepton standard so- 

 lutions. The rate of digestion was measured with the Sorensen 

 formol method. Tables 9 and 10 give the results of experiments 

 with Clostridium sporogenes and Clostridium histolyticum. 



It may be objected that in this case the Van Slyke method 

 might have given sharper values, but the only question we wanted 

 to study was the optimum for the action of the enzymes on pep- 

 ton, and for this purpose the formol method gives results which 



Fig. 2. 



pH 



pH 



can not be misinterpreted. In figure 2 the results are graphi- 

 cally represented. It is evident that the enzymes from Clos- 

 tridium sporogenes act in the same manner as to the pH optimum 

 as those from Clostridium histolyticum. For both the optimum 

 is at pH 6 and the range within which they act is pH 4 to 

 pH 8. Also in this case the enzymes acting on pepton seem to be 

 "tryptases." 



From figure 2 it is evident that the action on gelatin and the 

 action on pepton of the two anaerobes in relation to the hydrogen 



