%D 2002 %0 ARTICLE %T Ethanol production from corn cob hydrolysates by Escherichia coli KO11 . %J J Ind . Microbiol . Biotechnol . %V 29 ( 3 ) %P 124-8 %A de Carvalho %A Lima KG %A Takahashi CM %A Alterthum F %M pub12242633 %X Corn cob hydrolysates , with xylose as the dominant sugar , were fermented to ethanol by recombinant Escherichia coli KO11 . When inoculum was grown on LB medium containing glucose , fermentation of the hydrolysate was completed in 163 h and ethanol yield was 0 . 50 g ethanol/g sugar . When inoculum was grown on xylose , ethanol yield dropped , but fermentation was faster ( 113 h ) . Hydrolysate containing 72 . 0 g/l xylose and supplemented with 20 . 0 g/l rice bran was readily fermented , producing 36 . 0 g/l ethanol within 70 h . Maximum ethanol concentrations were not higher for fermentations using higher cellular concentration inocula . A simulation of an industrial process integrating pentose fermentation by E coli and hexose fermentation by yeast was carried out . At the first step , E coli fermented the hydrolysate containing 85 . 0 g/l xylose , producing 40 . 0 g/l ethanol in 94 h . Bakers yeast and sucrose ( 150 . 0 g/l ) were then added to the spent fermentation broth . After 8 h of yeast fermentation , the ethanol concentration reached 104 . 0 g/l . This two-stage fermentation can render the bioconversion of lignocellulose to ethanol more attractive due to increased final alcohol concentration .