Fructo-oligosaccharides (FOS) are low-calorie sweeteners that can be synthesized by the transfructosylation of sucrose using enzymes known as fructosyltransferases. However, enzymatic conversion is inhibited by the accumulation of glucose as a byproduct, which limits the conversion rate and yield. We therefore developed a semi-continuous production process in an enzyme membrane bioreactor (EMBR) system followed by fermentation with the probiotic bacterium . Filtration experiments were conducted in total recycle mode to evaluate membrane fouling using the resistance-in-series model. We found that fouling was predominantly caused by the accumulation of proteins at the membrane surface, which accounted for 29.6–95.5% of the total filtration resistance depending on the conditions. Using these data, we were able to achieve a stable filtration flux that fulfilled the requirements of the EMBR system by regulating the filtration parameters. The average concentration of total FOS in the products of EMBR reached 270 g·L, which was 4.6% higher than the batch process. Subsequently, the crude FOS preparation was treated by fed-batch fermentation with . The monosaccharides in the reaction mix (glucose and fructose) were completely removed, increasing the concentration of FOS to 195.9 g·L and the purity to 96.6%.

中文翻译：

---

使用酶膜生物反应器生产和纯化低聚果糖，并随后用益生菌凝结芽孢杆菌发酵


低聚果糖 (FOS) 是低热量甜味剂，可以通过使用称为果糖基转移酶的酶对蔗糖进行转果糖基化来合成。然而，酶促转化受到副产物葡萄糖积累的抑制，从而限制了转化率和产量。因此，我们在酶膜生物反应器 (EMBR) 系统中开发了一种半连续生产工艺，然后用益生菌发酵。在全循环模式下进行过滤实验，以使用串联电阻模型评估膜污染。我们发现，污垢主要是由膜表面蛋白质的积累引起的，根据条件的不同，蛋白质的积累占总过滤阻力的 29.6-95.5%。利用这些数据，我们能够通过调节过滤参数来实现稳定的过滤通量，满足 EMBR 系统的要求。 EMBR产品中总FOS的平均浓度达到270 g·L，比间歇工艺高出4.6%。随后，通过补料分批发酵处理粗低聚果糖制剂。反应混合物中的单糖（葡萄糖和果糖）被完全去除，FOS浓度提高至195.9 g·L，纯度提高至96.6%。