Departamento de Farmácia, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil.
Instituto de Biotecnologia, Universidade de Caxias Do Sul, PO Box 1352, Caxias do Sul, RS, 95001-970, Brazil.
Bioprocess Biosyst Eng. 2020 Jul;43(7):1265-1276. doi: 10.1007/s00449-020-02323-7. Epub 2020 Mar 14.
Lactobionic acid and sorbitol are produced from lactose and fructose in reactions catalyzed by glucose-fructose oxidoreductase and glucono-δ-lactonase, periplasmic enzymes present in Zymomonas mobilis cells. Considering the previously established laboratory-scale process parameters, the bioproduction of lactobionic acid was explored to enable the transfer of this technology to the productive sector. Aspects such as pH, temperature, reuse and storage conditions of Ca-alginate immobilized Z. mobilis cells, and large-scale bioconversion were assessed. Greatest catalyst performance was observed between pH range of 6.4 and 6.8 and from 39 to 43 °C. The immobilized biocatalyst was reused for twenty three 24-h batches preserving the enzymatic activity. The activity was maintained during biocatalyst storage for up to 120 days. Statistically similar results, approximately 510 mmol/L of lactobionic acid, were attained in bioconversion of 0.2 and 3.0 L, indicating the potential of this technique of lactobionic acid production to be scaled up to the industrial level.
乳醛酸和山梨醇是由乳糖和果糖在葡萄糖-果糖氧化还原酶和葡萄糖酸-δ-内脂酶的催化作用下反应生成的，这两种酶都是存在于运动发酵单胞菌细胞中的周质酶。考虑到之前建立的实验室规模的工艺参数，对乳醛酸的生物生产进行了探索，以将这项技术转移到生产领域。评估了 pH 值、温度、海藻酸钙固定化运动发酵单胞菌细胞的再利用和储存条件以及大规模生物转化等方面。在 pH 值为 6.4 到 6.8 之间和 39 到 43°C 的范围内观察到最大的催化剂性能。固定化生物催化剂在重复使用 23 个 24 小时批次后仍能保持酶活性。在长达 120 天的时间内，生物催化剂的储存过程中保持了其活性。在 0.2 和 3.0 L 的生物转化中，获得了约 510 mmol/L 的乳醛酸的统计学上相似的结果，表明该乳醛酸生产技术具有放大到工业规模的潜力。
