CONTINUOUS ETHANOL FERMENTATION AT 45 DEGREES-C USING KLUYVEROMYCES-MARXIANUS IMB3 IMMOBILIZED IN CALCIUM ALGINATE AND KISSIRIS

The thermotolerant ethanol-producing yeast strain Kluyveromyces marxia nus IMB3 was immobilized in calcium alginate and a 1:1 mixture of calc ium alginate and the porous volcanic mineral, kissiris. Immobilized pr eparations were placed in fixed-bed column bioreactors and continuous ethanol production by systems containing both immobilized preparations was examined at 45 degrees C with a 100 g/l glucose feed. The effect of residence time on product concentration, bioreactor efficiency and volumetric productivities have been examined and these were all higher in systems containing the alginate/kissiris mixed immobilization matr ix. Maximum ethanol concentrations produced by the continuous system r anged between 46 and 48 g/l representing efficiencies of 90-94%.