Submitted to: Applied Biochemistry and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/7/1995
Publication Date: N/A
Interpretive Summary: Corn fiber is a renewable resource available in sufficient quantities from the corn wet milling industry to serve as a potential low cost feedstock for production of fuel alcohol. However, typical corn fiber consists of a variety of sugars that traditional yeast cannot ferment to alcohol. Thus, this research was undertaken to screen yeasts from the ARS Culture Collection for conversion of the corn fiber sugar, arabinose, to fuel alcohol. Over 100 different types were screened. Seven yeasts were able to convert the sugar to alcohol. They did so slowly, and the final amounts of alcohol made were small. However, these yeasts may still be useful because genetic manipulation could improve their performance.
Technical Abstract: Utilization of pentose sugars (D-xylose and L-arabinose) derived from hemicellulose is essential for the economic conversion of biomass to ethanol. Xylose fermenting yeasts were discovered in the 1980's, but to date, no yeasts have been found that ferment L-arabinose to ethanol in significant quantities. We have screened 116 different yeasts for the ability to ferment L-arabinose and have found the following species able t ferment the sugar: Candida auringiensis, Candida succiphila, Ambrosiozyma monospora, and Candida sp. (YB-2248). Though these yeasts produced ethanol concentrations of 4.1 g/L or less, they are potential candidates for mutational enhancement of L-arabinose fermentation. These yeasts were also found to ferment D-xylose.