Understanding the formation of hemicellulose-polyphenol assemblies: case study of the xyloglucan-tannic acid system

Hemicellulose and polyphenols present attractive functional potential for the elaboration of biobased materials but their interaction remains scarcely studied. In this study, the interaction behavior of xyloglucan (XG) and tannic acid (TA) was systematically studied over XG concentration ranging from 0.25 g/L to 3 g/L and TA:XG weight ratio from 0.1 to 10. Three distinct types of assemblies identified as swollen coils, dense beads or aggregated beads were described using a combination of QCM-D, light scattering and thermodynamic characterizations. They differed in size and colloidal behavior, and their formation was primarily governed by hydrophobic interactions and steric repulsions. These findings provide new insights into the molecular mechanisms driving hemicellulose-polyphenol association and highlight their potential in the design of functional, plant-inspired materials.