46 
extent by lipase is of interest as indicating that the structural differ- 
ence between these radicals is without influence on the ly poly tic 
process. 
THE EFFECT OF THE ACID RADICAL ON THE LIPOLYTIC HYDROLYSIS ' 
OF ETHEREAL SALTS. 
In order to determine the effect of the acid radical of the ethereal 
salt on the rate of the hydrolysis of these compounds by lipase, the 
following experiments were carried out: 
Three solutions were prepared (1) containing 50 cc. N 100 methyl 
acetate, (2) 50 cc. N/ 100 methyl propionate, and (3) 50 cc. of IS! TOO 
methyl butyrate. Five cubic centimeters of a clear solution of lipase 
was added to each of these solutions, and after standing for one hour 
at ordinary temperature they were titrated with N 10 sodium hydroxide. 
The following results were obtained: 
Name of ester. 
Cubic centime- 
ters N/10 sodi- 
um hydroxide 
required. 
Per cent of 
hydrolysis. 
Methyl acetate 
0. 10 
2 
Methyl propionate 
Methyl butyrate 
. 45 
.95 
9 
19 
In a second series of experiments the conditions being the same as 
in the first, except that a different solution of lipase was employed, 
the following numbers were obtained: 
Name of ester. 
Cubic centime- 
ters N 10 sodi- 
um hydroxide 
required. 
Per cent of 
hydrolysis. 
Methyl acetate 
0. 30 
6 
Methyl propionate 
.60 
12 
Methyl butyrate _• 
1.10 
22 
A third series gave the following results: 
Name of ester. 
Cubic centime- 
ters N /10 sodi- 
um hydroxide 
required. 
Per cent of 
hydrolysis. 
Methyl acetate 
0. 10 
2 
Methyl propionate 
.40 
8 
Methyl butyrate 
. 75 
15 
J J 
Similar experiments were tried using the ethyl esters of these three 
acids, the other conditions of the experiments remaining the same. 
