Abstract To improve fermentation efficiency during L-tyrosine production, we established a novel method to produce L-tyrosine by repeated batch fermentation through cell recycling. According to the characteristics of the fermented broth, the cells were recovered using two dish centrifuges in series. First, L-tyrosine crystals were removed from the previous batch of fermented broth by selective centrifugation. The cells were then concentrated in another centrifuge and recycled for use in the next cycle of batch fermentation. L-tyrosine removal and cell recovery rates were 86% and 67%, respectively, in a centrifuge bioreactor. Through repeated batch fermentation, L-tyrosine productivity was increased by up to 44.1% compared with that for fed-batch fermentation, and the coupling of fermentation and separation was achieved, which is useful in reducing production costs. This study provides a rationale for the fermentation of low-solubility products by repeated batch or cell-recycle fermentation.

中文翻译：

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基于新型离心生物反应器的重复分批发酵技术提高L-酪氨酸产量

摘要 为了提高L-酪氨酸生产过程中的发酵效率，我们建立了一种通过细胞循环重复分批发酵生产L-酪氨酸的新方法。根据发酵液的特点，采用两台串联离心机回收细胞。首先，通过选择性离心从前一批发酵肉汤中去除 L-酪氨酸晶体。然后将细胞在另一台离心机中浓缩并循环用于下一个分批发酵循环。在离心生物反应器中，L-酪氨酸去除率和细胞回收率分别为 86% 和 67%。通过反复分批发酵，L-酪氨酸产率较补料分批发酵提高44.1%，实现了发酵与分离的耦合，这有助于降低生产成本。该研究为通过重复分批或细胞循环发酵来发酵低溶解度产品提供了基本原理。