Chemical, physico-chemical and cytotoxicity characterisation of xyloglucan from Guibourtia hymenifolia (Moric.) J. Leonard seeds

A water-soluble polysaccharide was obtained from Guibourtia hymenifolia seeds in a 54.2% yield (w/w). The Glc:Xyl:Gal molar ratio was 3.3:2.3:1. The methylation results and 1D/2D NMR spectra indicated the presence of xyloglucan (XG), the intrinsic viscosity of which was 665 mL/g. The molar mass (Mw), radius of gyration (Rg), hydrodynamic radius (Rh), and ρ (Rg/Rh) of XG were 8.43 × 105 g/mol, 97 nm, 61 nm, and 1.59, respectively, indicating a random coil and flexible conformation that was subsequently confirmed by the Mark–Houwink constant α (0.70). Atomic force microscopy analysis of XG adsorbed on silicon revealed that the chains are an average of 1.25-nm high, 28.9-nm wide and 131-nm long. Furthermore, a cytotoxicity assay indicated a high CC50 value (>3.3 mg/mL). These results suggest that this biopolymer has potential applications in different food technologies and biotechnological processes.