Effect of growth rate on the production of L-proline in the fed-batch culture of Corynebacterium acetoacidophilum

Corynebacterium acetoacidophilum RYU3161 was cultivated in a L-histidine-limited fed-batch culture. To investigate the effect of cell growth on the L-proline production, 5 L fed-batch culture was performed using an exponential feeding rate to obtain the specific growth rates (mu) of 0.04, 0.06, 0.08, and 0.1 h(-1). The results show that the highest production of L-proline was obtained at mu = 0.04 h(-1). The specific L-proline production rate (Q(P)) increased proportionally as a function of the specific growth rate, but decreased after it revealed the maximum value at mu = 0.08 h(-1). Thus, the highest productivity of L-proline was 1.66 g L-1 h(-1) at mu = 0.08 h(-1). The results show that the production of L-proline in C. acetoacidophilum RYU3161 has mixed growth-associated characteristics.