Performance of a cross-linked immobilized cell reactor with Zymomonas mobilis using synthetic and complex media for ethanol production

• Autores: E. C. Clausen, J. S. Cross, J. L. Vega
• Localización: Biomass and bioenergy, ISSN 0961-9534, Vol. 4, Nº 4, 1993, pág. 283
• Idioma: inglés
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• Resumen

  • The performance of ethanolic bacterium, Zymomonas mobilis, ATCC 31821, cross-linked to glutaraldehyde-treated, gelatin-coated spherical glass beads in an immobilized cell reactor (ICR) was evaluated for feed glucose concentrations of 150 and 200 g l−1. A synthetic medium, containing inorganic nitrogen and salts, and a complex medium, containing yeast extract, were both used. Two acid-base buffers, succinate and acetate, were added to the medium to regulate the pH of the broth in the ICR. The use of acetate in the broth increased the maximum volumetric ethanol productivity to 19 g l−1 h−1 compared to 16 gl−1 h−1 without acetate. Adding acetate to the medium increased the reactor operating life by decreasing cell growth rate. The reactors were operated from 34–57 days. The ICR fermentations conducted with the synthetic medium gave a comparable maximum volumetric ethanol productivity of 16 gl−1 h−1. Axial temperature distributions of 4–6°C were measured during the fermentation.