Improvement of l-Lactic Acid Production under Glucose Feedback Controlled Culture by Lactobacillus rhamnosus

In this study, a glucose feedback controller had been designed. Under the controller, the glucose concentration in l-lactic acid culture could be automatically controlled at 15 ± 1 g/L. Furthermore, l-lactic acid production by Lactobacillus rhamnosus LA-04-1 in fed-batch culture was significantly increased to 170 g/L l-lactic acid using the controller compared with 130 g/L l-lactic acid in pulse fed-batch and 135 g/L in l-lactic acid constant feed rate fed-batch cultures. The results showed that the controller was effective at glucose control in l-lactic acid culture. The control strategy could also be used in other fermentation processes.