A practical approach to producing the single-arm linear dextrin, a chimeric glucosaccharide containing an (?-1?4) linked portion at the nonreducing end of an (?-1?6) glucochain

How to improve the solubility of linear dextrins (LD) and retain their characteristic helix amphiphilic cavities with flexible embedding capability, is a question worth exploring without adding new chemical groups. The strategy presented in this study is to attach a highly flexible (alpha-1-* 6) glucochain at the reducing end of LD by preparing a new type of dextrin, referred to as single-arm linear dextrin (SLD). In the actual synthesis, an (alpha-1-* 6) linked oligosaccharide of DP 10.7 (PDI = 1.28) was formed by extension of glucose units onto sucrose (2 M) by using L940W mutant of the glucansucrase GTF180-Delta N firstly. Next using gamma-CD as glucosylation donor gamma-CGTase extended this (alpha-1-* 6) glucochain with (alpha-1-* 4) bonds. SLD is a chimeric glucosaccharide comprising an (alpha-1-* 4) linked part (DP 10.5) attached to the nonreducing end of an (alpha-1-* 6) glucochain as verified by enzyme fingerprinting and 1H NMR. Furthermore, SLD was validated to show greatly improved solubility and dis-persibility of resveratrol in water, as indicated by a 3.12-fold enhancement over the solubility in the presence of 0.014 M SLD. This study provided a new strategy for solving the solubility problem of LD and opens possibilities for new design of the fine structure of starch-like materials.

Automated summary

How to improve the solubility of linear dextrins (LD) without adding new chemical groups has been explored in this study by attaching a flexible glucochain at the reducing end to create a single-arm linear dextrin (SLD). The synthesis involved extending glucose units onto sucrose and subsequently extending the glucochain with gamma-CD. SLD demonstrated significantly improved solubility and dispersibility of resveratrol in water, providing a new strategy for addressing the solubility problem of LD and potential design of starch-like materials.