Fig. 6.

Production of n-butanol with the high cell density. The fermentation was carried out using E. coli strain BuT-16 at various cell densities in M9Y medium containing 30 g/L crude glycerol. The maximum production of n-butanol was obtained for the case with OD₅₅₀ of 1 at 48 h and with OD₅₅₀ of 5 or 10 at 36 h. The fermentation of the strain became sluggish after the peak production. The experiments were duplicated. Keys: 1 OD₅₅₀ of 1; 2 OD550 of 5; 3 OD₅₅₀ of 10. Symbols production (gray); productivity (black)