CHEMICAL DYNAMICS OF ANIMAL NUTRITION 147 



Series III (V). With another sample of the products of digestion 

 of caseine the following results were obtained : 



Products of digestion alone N = 1117 c.c H 2 SO 4 (20 c.c.) 



Time With T.D. * Control * Difference 



8 hours 128-5 138*0 9-5 



24 ,, 140-0 J 35' 2 4'8 



Experiments were also made to determine whether previous 

 treatment of the product ot tryptic digestion with mucous membrane 

 of the small intestine exerted any influence on the inhibitory power. 

 No difference could, however, be detected. 



Series III (<?). It will be shown below that acids accelerate 

 autolysis, whereas alkalis inhibit it ; it was, therefore, of interest to 

 determine whether the products of tryptic digestion inhibit autolysis 

 in distinctly acid solutions, especially as it is somewhat difficult to be 

 sure of the reaction to litmus of the products of digestion. 



The sample of digestion products used had been prepared by 

 digesting an alkaline solution (5 per cent.) of caseine for three months 

 with Rhenania trypsine. 



Amount of acid used for 4. grams liver = 20 c.c. acetic acid 



10 



To this was added 10 c.c. T.D. solution = 95-5 - _ H 2 SO 4 



Time With T.D. * Control A * Control B * 



2 hours Io6'0 I>6'3 11 S'S 



4 115-5 129-8 131-0 



6 123*3 H4-' 5 H4'5 



Control A was made by boiling the mixture incubated with water 

 before adding the T.D. solution ; then adding trichloracetic acid. In 

 control B the T.D. was added first ; then the mixture boiled and 

 trichloracetic acid added. These results clearly indicate the marked 

 inhibitory actiort of the products' of tryptic digestion. 



Series III (/). Attempts to reverse autolysis. 



4 grams of liver in each case were incubated with 20 c.c. ^ 



lactic acid. After i\ and 3^ hours respectively, the following mixtures 

 were added : 



