Structure of nascent microbial cellulose - V. Influence of number of sulfonate group in fluorescent brightener on crystal structure of microbial cellulose

The influence of the number of sulfonate groups in a Fluorescent Brightener on the crystal structure of microbial cellulose was examined by X-ray diffraction and solid state C-13 NMR spectroscopy. All products obtained from Acetobacter xylinum-culture in the presence of a Fluorescent Brightener with 2 (FB), 9 (FWA2), or 6 sulfonate groups (FWA3) were crystalline complexes that contained a dye between cellulose sheets corresponding to the (ITO) plane of microbial cellulose. Cellulose regenerated from the FB complex forms a cellulose I-beta rich structure. whereas cellulose regenerated from FWA2 and FWA3 complexes form cellulose II. The influence of a Fluorescent Brightener on the crystal formation of regenerated microbial cellulose clearly differs according to the number of sulfonate groups in a dye. The nascent structure of microbial cellulose may he the structure that the conformation and arrangement of the cellulose chain changes when a dye adheres to it.