FUEL ETHANOL-PRODUCTION FROM CORN FIBER - CURRENT STATUS AND TECHNICAL PROSPECTS

Corn fiber, which consists of about 20% starch, 14% cellulose, and 35% hemicellulose, has the potential to serve as a low cost feedstock for production of fuel ethanol. Currently, the use of corn fiber to produ ce fuel ethanol faces significant technical and economic challenges. I ts success depends largely on the development of environmentally frien dly pretreatment procedures, highly effective enzyme systems for conve rsion of pretreated corn fiber to fermentable sugars, and efficient mi croorganisms to convert multiple sugars to ethanol. Several promising pretreatment and enzymatic processes for conversion of corn fiber cell ulose, hemicellulose, and remaining starch to fermentable sugars were evaluated. These hydrolyzates were then examined for ethanol productio n in bioreactors, using genetically modified bacteria and yeast. Sever al novel enzymes were also developed for use in pretreated corn fiber saccharification.