Aeration and fermentation strategies on nisin production.

Abstract

To optimize nisin production in Lactococcus lactis by using different aeration and fermentation strategies. The nisin titer and specific nisin production rate reached maximum values of 11,900IU/ml and 4110IU/g/h, respectively, in aerobic batch fermentation with glucose as C source. These values were higher than in anaerobic batch fermentation (10,700IU/ml and 3260IU/g/h, respectively). The maximum specific nisin production rates appeared earlier in aerobic batch fermentation, which suggests that nisin production is stimulated by aeration. Different fermentation strategies were compared: maximum nisin production (15,400IU/ml) was achieved with fed-batch fermentation with a variable rate of feeding under aerobic conditions. Nisin production can be stimulated by aeration, which goes against the typical conditions involving strict anaerobiosis.