THE EFFECT OF MN2-PRODUCTION FROM LACTOSE USING KLUYVEROMYCES-MARXIANUS IMB3 IMMOBILIZED IN MAGNETICALLY RESPONSIVE MATRICES( ON ETHANOL)

The thermotolerant, ethanol producing yeast strain, a marxianus IMB3 w as immobilized in calcium alginate containing magnetically responsive Fe3O4 particles. In these studies the beta-galactosidase derived from K. marxianus IMB3 was immobilized onto the Fe3O4 particles prior to in clusion into the alginate matrix. Ethanol production by the immobilize d microorganism in the presence of Fe3O4 reached a maximum of 16 g/L o n 40 g/L lactose whereas prior immobilization of the enzyme to the par ticles and inclusion into the alginate matrix increased ethanol produc tion to a maximum concentration of 18 g/L. When Mn2+ was incorporated into fermentations containing the immobilized enzyme in the alginate m atrix, ethanol production increased further to a maximum concentration of 20 g/L. In addition, the behaviour of the magnetically responsive biocatalyst containing the co-immobilized enzyme was examined in a bat ch-fed system in the presence and absence of Mn2+.