[VoL. 3 
464 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
DIASTASE 
Hartig (’78) was the first to mention the digestion of starch 
by a wood-destroying fungus, Fomes annosus, but not until 
the work of Bourquelot (’93-’96) did we know that diastase 
is widely distributed in these higher fungi. Bourquelot’s 
work was especially with the sporophores of Polyporus sul- 
phureus. Kohnstamm (’00) demonstrated the presence of 
diastase in Merulius lacrymans, Polyporus squamosus, and 
Armillaria mellea, and in 1906 Buller verified this work with 
the juice from the sporophores of Polyporus squamosus. 
Diastase was found present in both the mycelium and sporo- 
phores of L. saepiaria. 
Potato starch was made up into a 1 per cent paste in the 
manner which is commonly used in this laboratory in the 
advanced plant physiology course conducted by Professor 
Duggar. Two and one-half grams of potato starch in 150 ce. 
of distilled water were brought to boiling, while constantly 
stirred. This was transferred to a flask containing about 600 
ec. of hot distilled water. The whole was boiled in a reflux 
condenser for about 2 hours. After cooling the paste was 
made up to a liter by adding distilled water. To the soluble 
starch thus prepared about 1 per cent toluol was added as an 
antiseptic. 
A series of experiments was set up as for maltase but using 
the starch paste as a substrate. After 4 hours the mycelial 
dispersion showed decided indication of the presence of reduc- 
ing sugars, while the sporophoral dispersion after 8 hours of 
incubation showed comparatively less. This work was not 
quantitative, however, and later experiments were conducted 
so that quantitative results could be taken. For this work I 
used the fungous powder prepared from mycelium grown on 
carrot juice, described under invertase. The fungous powder 
was used directly without extracting the enzymes. А 1 рег 
cent starch paste was made as above described and this used 
for the substrate. In each experiment 50 ce. of the paste were 
used. To this were added 2 grams of the fungous powder and 
enough toluol to act as an antiseptic. Control experiments 
were set up in which the fungous powder had been autoclaved. 
