ETHANOL-PRODUCTION FROM NATIVE CASSAVA STARCH BY A MIXED CULTURE OF ENDOMYCOPSIS-FIBULIGERA AND ZYMOMONAS-MOBILIS

The conversion of starch from unhydrolyzed cassava flour to ethanol by a pure culture of Endomycopsis fibuligera and by a co-culture of this amylolytic yeast and the bacterium Zymomonas mobilis was studied. The best overall results were obtained using the mixed culture. After 96 h of fermentation of a medium containing 150 g/l initial cassava starc h, an ethanol concentration of 31.4 g/l, a productivity of 0.33 g etha nol/l x h and a yield of 0.21 g ethanol/g initial starch were reached. The highest yield (0.37 g/g) was obtained after 48 h when using a med ium containing 50 g/l initial starch.