Nicotine is the chief addictive ingredient in cigarettes, cigars, and snuff, and has extensive applications in the agricultural and pharmaceutical industries. The synthesis of nicotine using free enzyme systems has been widely reported in literature; this approach chiefly utilizes the alkaloid myosmine and the enzymes imine reductase (IRED) as well as glucose dehydrogenase (GDH), and generates the intermediate (S)-nornicotine. Free enzymes are not reusable, thereby resulting in higher cost of production. The use of recyclable immobilized enzymes is an efficient approach for lowering the costs and improving the efficiency of production. In the current study, we present an efficient and environment-friendly approach utilizing immobilized enzymes for synthesizing (S)-nornicotine using batch and continuous flow reaction processes. A highly active coimmobilized enzyme system was successfully obtained by coimmobilizing IRED and GDH on the resin LXTE-706. The immobilized enzymes were amenable to repeated usage for at least 40 operation cycles in the batch mode of operation and yielded a product with a high chiral purity of >99.90%, effectively reducing the overall production cost. Furthermore, a space–time yield of 211.47 g/Lh was obtained using a continuous mode of operation, which is 289.7-fold higher than that obtained with batch mode.

中文翻译：

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在间歇式和连续流反应系统中使用共固定 IRED 和 GDH 高效合成 (S)-降烟碱

尼古丁是香烟、雪茄和鼻烟中的主要成瘾成分，在农业和制药行业有着广泛的应用。使用游离酶系统合成尼古丁已在文献中广泛报道；该方法主要利用生物碱肌胺和亚胺还原酶（IRED）以及葡萄糖脱氢酶（GDH），并生成中间体（S）-降烟碱。游离酶不可重复使用，从而导致生产成本较高。使用可回收的固定化酶是降低生产成本、提高生产效率的有效途径。在当前的研究中，我们提出了一种利用固定化酶通过间歇和连续流动反应过程合成（ S ）-降尼古丁的高效且环境友好的方法。通过将IRED和GDH共固定在树脂LXTE-706上，成功获得了高活性的共固定化酶体系。固定化酶可在批量操作模式下重复使用至少40个操作周期，得到的产品手性纯度高达>99.90%，有效降低了总体生产成本。此外，使用连续操作模式获得的时空产率为 211.47 g/Lh，比间歇模式高 289.7 倍。