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目的 建立一种高残糖-pH反复重碱化震荡发酵(F4)策略,提高乳酸片球菌素(pediocin)的发酵效价.方法 在发酵的第一阶段采用间歇发酵,初始葡萄糖浓度为8.8 g/L;待发酵液中的残留葡萄糖浓度低于2g/L时开始第二阶段发酵;在第二阶段,使发酵液中的残糖浓度始终维持在20 g/L左右,同时,每隔6h将发酵液的pH值调到6.5,维持pH值重碱化震荡.结果 由F4策略发酵产生的pediocin单位效价是对照策略F1和F2的3倍、F3的1.7倍,达到24000 AU/mL.结论 F4策略既能维持菌体的稳定生长,又可大量积累pediocin,适用于大规模生产pediocin的补料流加.“,”Objective To improve the pediocin yield by designing a novel high residual sugar and re-alkalized feeding(F4) strategy.Methods ① The initial glucose concentration was 8.8 g/L in the first phase;② When the residual glucose concentration was lower than 2 g/L,the second phase started,and the glucose concentration kept about 20 g/L in the whole second phase;at the same time,the pH values of fermentation broth were raised to 6.5 every 6 h,which make the pH value re-alkalize repeatedly.Results The max titer of pediocin reached 24 000 AU/mL in the optimized feeding strategy F4.The pediocin yield of F4 strategy is 3,3,and 1.7 times of F1,F2 and F3 strategies.Conclusion F4 strategy can not only increase the cell concentration,but also improve the yield of pediocin,which is suitable for mass production of pediocin.