THE UTILIZATION OF CERTAIN PENTOSES 
xylan did not take place immediately but that the amount of alcohol- 
soluble furfurol-yielding substance (xylose) increased the longer the 
extract was allowed to act. The rate of hydrolysis was much more 
rapid at first and gradually decreased almost, if not quite, to zero. 
In contrast to the unboiled preparation there seemed to be no increase 
in the alcohol-soluble furfurol-yielding material in the boiled controls ; 
that is, heating to 100° C. apparently rendered the extract incapable 
of affecting the xylan. 
While it seemed probable that xylose was liberated by the action 
of the extract of the fungus upon xylan it was deemed advisable to 
attempt to crystallize the sugar from the alcohol-soluble portion of 
the preparation. In order to obtain a sufficient quantity, a number 
of flasks of the xylan and extract of the fungus mycelium were pre- 
pared in the usual manner excepting that larger quantities were used. 
These preparations were kept in the incubator for about a week, 
the unchanged xylan precipitated as before, the alcohol extract con- 
centrated under reduced pressure, decolorized with animal charcoal 
and. filtered. The filtrate was allowed to evaporate slowly over 
sulphuric acid in a desiccator and crystals were formed. These 
crystals were separated from the mother liquor and recrystallized. 
The substance did not melt sharply but apparently fused between 
141° and 144° C, This was probably due to impurities present. The 
crystals reduced Fehling's solution and formed the characteristic 
phloroglucid when boiled with a hydrochloric acid solution of phloro- 
glucin. The phenylhydrazine derivative was similar to the osazone 
of xylose as prepared in this study in color, crystal form, solubility 
and melting point. The compound when dissolved in water and 
treated with cadmium carbonate and bromine formed the charac- 
teristic crystals of the double salt of cadmium xylonate and cadmium 
bromide described by Widstoe and Tollens^^ and observed in the 
present study with xylose. These properties all agree closely with 
the properties of xylose. 
It is evident then that xylan is hydrolyzed under aseptic conditions 
by the extract of the fungus and that xylose is formed. No attempt 
was made to determine whether intermediate products of hydrolysis 
were present as might well be the case. 
In these experiments on the effect of the fungus Glomerella cingulata 
21 Widstoe, J. A., und Tollens, B. Ueber Arabinose, Xylose und Fucose aus 
Traganth. Bericht. Deutsch. Chem. Ges. 33: 132-143, 1900. 
