半连续发酵对提高阿维菌素放罐体积的影响

Effect of Semi-Continuous Fermentation on Improvement of Final Fermentation Volume of Avermectin

为提高阿维菌素发酵放罐体积,研究了其半连续发酵中的补料工艺。在100 L、50 L发酵罐中进行平行试验,发酵中后期分别补入体积分数15%的补料培养基和培养50 h后的发酵液,比较效价增长情况;研究分别补入体积分数为15%和8%的发酵液对效价增长的影响,并以试验效价与回归效价差的正负为确定发酵放罐时间的依据。结果表明,补入发酵液(斜率K=0.0375)较补入补料培养基(斜率K=0.0346)效价增长得更快;补入体积分数15%的发酵液(斜率K=0.0364)比补入体积分数8%的发酵液(斜率K=0.0298)效价增长更快,但同时稀释作用也更明显,宜在补入发酵液72 h后放罐;补入体积分数8%的发酵液效价增长相对较慢,但稀释作用相对不太明显,宜在补入发酵液48 h后放罐。阿维菌素发酵带放后补入培养50 h后的发酵液,可以提高设备产能,增加阿维菌素发酵放罐体积。

In order to improve the final fermentation volume of Avermectin,we studied the feeding process in semi-continuous fermentation.Moreover,we performed the parallel experiments in 100 L and 50 L fermentation tanks,and added 15%(volume fraction,the same below)feed liquid and the fermentation broth after being cultured for 50 h during the middle and late stages of fermentation,respectively,to compare the increase of titer.Furthermore,we studied the effects of adding 15%and 8%fermentation broth on the increase of titer,and determined the release time of fermentation tank by the positive and negative difference between test titer and regression titer.The results show that,adding the fermentation broth will accelerate the increase of titer than that of adding the feed liquid;adding the 15%fermentation broth will accelerate the increase of titer than that of adding the 8%fermentation broth,but the dilution effect is more obvious at the same time,and the harvesting is preferred to be at 72 h after adding the fermentation broth;adding the 8%fermentation broth will result in a relatively slower increase of titer while the dilution effect is relatively smaller,and the harvesting is preferred to be at 48 h after adding the fermentation broth.Adding the fermentation broth after being cultured for 50 h in the semi-continuous fermentation will improve the yield of devices and increase the find fermentation volume of Arermectin.