Abstract Fe3O4-Arg was selected as the optimal carrier due to its high activity recovery of immobilized cells in the preparation of Fe3O4-Arg-Cells. The optimal immobilization conditions for the preparation of Fe3O4-Arg-Cells were 30 °C, 4 h, pH 7, and 3 g dry yeast. The activity recovery of immobilized cells reached 76.8 %. For a batch reduction in a shaker in an alternating magnetic field, Fe3O4-Arg-Cells were used as a catalyst to gain ethyl (R)-4-chloro-3-hydroxybutyrate ((R)-CHBE). For further improvement in reduction productivity, a continuous reduction in the magnetic fluidized bed reactor system (MFBRS) was completed. Under their optimal transformation conditions, it took 24 h for Fe3O4-Arg-Cells to complete the conversion of ethyl 4-chloro-3-oxobutanoate (COBE) (0.8553 mol/L) in the shaker and only 8 h for the batch reduction in an alternating magnetic field. Continuous reduction in MFBRS provided new ideas for the efficient production of (R)-CHBE; 1.5882 mol/L (10 mL) of COBE can be completely converted in 6 h. The conversion and enantiomeric excess (e.e.) of (R)-CHBE were 100 % and above 99.9 % respectively, in the three reaction systems mentioned above.

中文翻译：

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使用氨基酸修饰的磁性纳米颗粒通过固定细胞合成 (R)-4-氯-3-羟基丁酸乙酯

摘要 Fe3O4-Arg在制备Fe3O4-Arg-Cells时，固定化细胞的活性恢复率高，因此选择Fe3O4-Arg作为最佳载体。制备 Fe3O4-Arg-细胞的最佳固定条件是 30 °C、4 h、pH 7 和 3 g 干酵母。固定化细胞活性恢复率达到76.8%。对于在交变磁场中在振荡器中进行批量还原，Fe3O4-Arg-Cells 被用作催化剂来获得 (R)-4-氯-3-羟基丁酸乙酯 ((R)-CHBE)。为了进一步提高还原生产率，完成了磁流化床反应器系统（MFBRS）的连续还原。在最佳转化条件下，Fe3O4-Arg-Cells 需要 24 小时才能完成 4-氯-3-氧代丁酸乙酯 (COBE) (0. 8553 mol/L），在交变磁场中批量还原仅需 8 小时。MFBRS 的不断降低为 (R)-CHBE 的高效生产提供了新思路；1.5882 mol/L (10 mL) COBE 可在 6 小时内完全转化。在上述三个反应体系中，(R)-CHBE 的转化率和对映体过量 (ee) 分别为 100% 和 99.9% 以上。