Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany; Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Ohlebergsweg 12, 35392, Giessen, Germany.
Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany; Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Ohlebergsweg 12, 35392, Giessen, Germany.
Bioresour Technol. 2021 Dec;342:125969. doi: 10.1016/j.biortech.2021.125969. Epub 2021 Sep 20.
Fructo-oligosaccharides (FOS) are prebiotic sugar substitutes that can be produced from sucrose using fructosyltransferases (FTases). However, the economic value of this process is limited by inefficient product purification and enzyme reusability. In this study, enzyme-free FOS preparations were produced by immobilizing the FTase on resin carriers. This also increased the catalytic selectivity of the enzyme. However, the crude FOS preparations still contained high concentrations of monosaccharide byproducts and residual disaccharides that must be removed because they lack prebiotic activity. A hybrid process was developed in which fed-batch fermentation was combined with the probiotic bacterium Bacillus coagulans (which selectively utilizes monosaccharides) and the simultaneous conversion of residual sucrose using the FTase to increase FOS purity. This process depleted the monosaccharides and increased the concentration of FOS to 130-170 g·L. The residual sucrose was converted to FOS by the immobilized FTase, increasing the overall purity of FOS to 92.1%.
果寡糖（FOS）是一种可以用果糖基转移酶（FTase）从蔗糖中合成的益生元糖替代品。然而，这个过程的经济价值受到低效的产品纯化和酶的可重复使用性的限制。在这项研究中，通过将 FTase 固定在树脂载体上，制备了无酶的 FOS 制剂。这也提高了酶的催化选择性。然而，粗 FOS 制剂仍然含有高浓度的单糖副产物和残留的二糖，因为它们缺乏益生元活性，所以必须去除。开发了一种混合工艺，将分批发酵与益生菌凝结芽孢杆菌（选择性利用单糖）相结合，并同时使用固定化 FTase 转化残留的蔗糖，以提高 FOS 的纯度。这个过程消耗了单糖，并将 FOS 的浓度提高到 130-170 g·L-1。剩余的蔗糖被固定化的 FTase 转化为 FOS，使 FOS 的总纯度提高到 92.1%。
