12 
Journal of Agricultural Research 
Vol. II, No. i 
will increase the production of the corresponding enzym. In accordance 
with this principle, the addition of ethyl butyrate should stimulate the 
production of lipase. 
Preliminary experiments were conducted to discover the most active 
preparation of enzym. Three methods were tried: 
(1) The “acetonedauerhefe” method of Albert, Buchner, and Rapp 
(i, p. 2376). 
(2) Fresh mycelium was triturated with water and powdered glass, 
filtered, and the filtrate used. 
(3) Washed, air-dried mycelium was triturated with dry powdered 
glass and the pulverized mixture used. 
On tributyrin in water, blue with litmus, and with toluene as anti¬ 
septic, the “dauer” preparation gave no pink in six days, the water 
extract Showed slight acidity in six days, and the fresh powdered 
mycelium showed a distinct acidity in 24 hours. Controls of boiled 
enzym preparations showed no acidity in six days. On ethyl butyrate 
made distinctly alkaline with one drop of decinormal sodium hydroxid 
the enzym extract showed acidity in 24 hours and the mycelium powder 
in 4 hours. Controls showed acidity in five days. 
From these preliminary experiments the following conclusions were 
drawn: 
The “dauer” preparation is unreliable for the study of lipase in the 
mycelium of Penicillium roqueforti; a water-soluble lipase can be 
extracted from the mycelium; and the most active preparation is the 
fresh pulverized mycelium. 
A more accurate measure of the activity of the lipase at 38° C. to 40° C. 
was made on tributyrin, triacetin, ethyl butyrate, and ethyl acetate. 
For this study 1 gram of the air-dried mycelium was triturated with 4 
grams of powdered glass, and 0.5 gram of the powder was added to 0.5 c. c. 
of the ester in 50 c. c. of distilled water contained in a small Erlenmeyer 
flask. The water was covered with a thin layer of toluene. Boiled 
enzym preparations were used in the controls. The flasks were tightly 
stoppered. At the end of two weeks the solutions were filtered and 
titrated with decinormal barium hydroxid. The results are given in 
Table VIII. 
Table VIII. — The action of the lipase of Penicillium roqueforti on esters. 
[Acidity in decinormal c. c. j 
* 
Ester. 
Days. 
Unboiled 
enzym. 
Control, 
boiled 
enzym. 
Tributyrin. 
14 
0. 67 
O. 08 
Triacetin. 
14 
.81 
. 51 
Ethyl butyrate... 
14 
I - 37 
. 20 
Ethyl acetate. 
14 
i-31 
. 24 
