为了解除发酵过程中目标产物乳链菌肽(nisin)的抑制,研究了发酵泡沫分离耦合。通过正交试验确定了合适的耦合操作条件:气速40 mL/min、pH 5.75、通气时间90 min。在此条件下进行实验,nisin失活最小(6.1%)。随后,在耦合操作的基础上进行了补料实验。结果表明,在发酵末期时nisin总效价(4 813 IU/mL)和总产量(3.37×106IU)相对于对照组的总效价(4 097 IU/mL)和总产量(2.46×106IU)分别提高了17.5%和37.0%。

The fermentation technology coupling with foam separation was studied to relieve the inhibition of target product nisin during fermentation of Lactococcus lactis subsp.lactis ATCC 11454.Coupled operation conditions were determined by Orthogonal-designing experiments as follows: air velocity 40 mL/min,pH 5.75,and aeration duration 90 min.Under the condition,a minimal nisin inactivity rate(6.1%) was achieved.Based on the coupled experiments,fed-batch fermentation was conducted.The results showed that the total nisin activity(4 813 IU/mL) and production(3.37×106 IU) at the end of fermentation increase by 17.5% and 37.0% compared with those in the control group which were 4 813 IU/mL and 2.46×106 IU,respectively.These provided a promising method for industrial production of nisin.