Ethanol production byZymomonas mobilis in continuous culture at high glucose concentrations

Summary Ethanol production byZ.mobilis has been studied in continuous culture with 10, 15 and 20% glucose media. At 10% glucose, steady state conditions were achieved under glucose-limited conditions. At 15 and 20% glucose, the glucose was not fully metabolized even at low dilution rates and oscillatory behavior was evident. It is proposed that ethanol inhibition of growth is responsible for these phenomena. Comparison of kinetic parameters with those from previously published batch data revealed similar values. The maintenance energy coefficient (m) forZ.mobilis was relatively high and was calculated as 1.6 g/g/h for 10% glucose and 3.1 g/g/h for 15% glucose.