Product solubility control in cellooligosaccharide production by coupled cellobiose and cellodextrin phosphorylase

We provide here the underlying data of the scientific publication "Product solubility control in cellooligosaccharide production by coupled cellobiose and cellodextrin phosphorylase". Please find the abstract below: Soluble cellodextrins (linear β‐1,4‐D‐gluco‐oligosaccharides) have interesting<br> applications as ingredients for human and animal nutrition. Their bottom‐up synthesis<br> from glucose is promising for bulk production, but to ensure a completely watersoluble<br> product via degree of polymerization (DP) control (DP ≤ 6) is challenging.<br> Here, we show biocatalytic production of cellodextrins with DP centered at 3 to 6<br> (~96 wt.% of total product) using coupled cellobiose and cellodextrin phosphorylase.<br> The cascade reaction, wherein glucose was elongated sequentially from α‐glucose<br> 1‐phosphate (αGlc1‐P), required optimization and control at two main points. First,<br> kinetic and thermodynamic restrictions upon αGlc1‐P utilization (200 mM; 45°C,<br> pH 7.0) were effectively overcome (53% → ≥90% conversion after 10 hrs of reaction)<br> by in situ removal of the phosphate released via precipitation with Mg2+. Second, the<br> product DP was controlled by the molar ratio of glucose/αGlc1‐P (∼0.25; 50mM<br> glucose) used in the reaction. In optimized conversion, soluble cellodextrins in a total<br> product concentration of 36 g/L were obtained through efficient utilization of the<br> substrates used (glucose: 98%; αGlc1‐P: ∼80%) after 1 hr of reaction. We also showed<br> that, by keeping the glucose concentration low (i.e., 1–10 mM; 200mM αGlc1‐P), the<br> reaction was shifted completely towards insoluble product formation (DP ∼9–10). In<br> summary, this study provides the basis for an efficient and product DP‐controlled<br> biocatalytic synthesis of cellodextrins from expedient substrates.