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LON A. HAWKINS 
one percent concentration. In preparing the culture media the 
solutions of salts were made up at a somewhat higher concentration 
than finally desired and sterilized in the autoclave, then diluted to the 
proper concentration by the addition of the sugar solutions which 
had been sterilized separately in a steamer. The culture solutions 
were inoculated and the fungus allowed to grow twelve days in an 
incubator at about 28° C. At the end of this time the mycelium 
was removed and dried to constant weight. The culture solutions 
were tested for reducing sugars, and the solutions which originally 
contained xylose or arabinose were tested for pentoses. Traces only 
were found. The sugar had been almost entirely removed from the 
solution by the fungus. The weight of the mycelium from the twelve 
flasks is shown in Table II. 
Table II 
Comparative Yields of Mycelium, Expressed in mg. Dry Weight, from Cultures of 
Glomerella cingulata on Nutrient Salt Solutions with Glucose, Arabinose or 
Xylose as Source of Carbon 
Glucose Arabinose Xylose 
365.1 382.0 401.4 
347-5 372.3 383-8 
317-3 337-2 380.1 
365-3 349-5 386.1 
The pentoses seem to be slightly better sources of carbon than 
glucose. Xylose is apparently the best, though the difference is not 
great. It is very evident that the pentoses are readily utilized by 
this fungus. 
A series of culture solutions was next made using arabin and two 
xylans, one prepared from rye straw and the other the commercial 
preparation. The yield in dry weight of fungus mycelium with the 
amount of furfurol-yielding material used in each case is given in 
Table III. The amount of arabin or xylan used was determined by 
Table III 
Comparative Yields of Mycelium and Amount of Pentosan Used with Cultures of 
Glomerella cingulata Grown upon Nutrient Salt Solutions with Xylan or 
Arabin as the Source of Carbon 
Commercial Xylan 
Xylan Prepared from Rye Straw 
Arabin 
Yield, mg. 
Percentage of Xylan 
Used 
, , I Percentage oi Xylan 
Yield, mg. i Used 
Yield, mg. 
Percentage of Arabin 
Used 
202.2 
196.0 
179.9 
205.4 
86.0 
85.0 
90.0 
87.0 
230.9 88.0 
74-3 
64.6 
98.2 
79.8 
15-0 
14.0 
13.0 
15.0 
