Fig. 1.

Fed-batch culture of M. gryphiswaldense strain MSR-1 cells in a 7.5-liter autofermentor supplemented with feed B (see the text). (A) Cell growth curve. The cell density (i.e., the OD₅₆₅) reached a maximum of 19.4 at 44 h. (B) Concentrations of lactate (▪) and NH₄⁺ (▵). Each was controlled at a low level suitable for cell growth. (C) The Fe²⁺/Fe³⁺ concentration in fermentor increased with time but remained within the cell tolerance range. (D) Relation of C_mag (▵) and dO₂ (▪). The C_mag increased rapidly as dO₂ declined to 0% at 12 h, but then decreased in the late logarithmic phase and the stationary phase.