Production of Ethanol from d-Xylose by Using d-Xylose Isomerase and Yeasts.
d-Xylulose, an intermediate of d-xylose catabolism, was observed to be fermentable to ethanol and carbon dioxide in a yield of greater than 80% by yeasts (including industrial bakers' yeast) under fermentative conditions. This conversion appears to be carried out by many yeasts known for d-glucose fermentation. In some yeasts, xylitol, in addition to ethanol, was produced from d-xylulose. Fermenting yeasts are also able to produce ethanol from d-xylose when d-xylose isomerizing enzyme is present. The results indicate that ethanol could be produced from d-xylose in a yield of greater than 80% by a two-step process. First, d-xylose is converted to d-xylulose by xylose isomerase. d-Xylulose is then fermented to ethanol by yeasts.
Gong
C S
CS
Laboratory of Renewable Resources Engineering, A. A. Potter Engineering Center, Purdue University, West Lafayette, Indiana 47907.
Chen
L F
LF
Flickinger
M C
MC
Chiang
L C
LC
Tsao
G T
GT