LAUSR

Arabinoxylan oligosaccharides (AXOS) are a complex mixture of cereal derived, water soluble prebiotics, obtained by enzymatic hydrolysis of arabinoxylan, a group of dietary fibers exerting numerous nutritional and health-beneficial effects. Such complex biomolecular mixtures are notoriously difficult to characterize without initial physical fractiona-tion. Here we present the in-situ analysis of AXOS using a variety of state-of-the-art sensitivity-enhanced 13C-DOSY methods, enabling virtual separation and identification of the components. Three dimensional correlation plots dis-playing 13C diffusivity (DOSY: Diffusion Ordered SpectroscopY), relaxation parameters (TOSY: raTe of relaxation Or-dered SpectrscopY) and chemical shift offer a unique way to elucidate the composition of mixtures. We have demon-strated this multifaceted 13C probed correlation strategy in standard mixtures of aliphatic and aromatic compounds, before implementing it on AXOS. These 3D-DOSY-TOSY plots in combination with 2D-NMR correlation experiments offer unprecedented clarity for assigning chemical functions, molecular size distribution and dynamics of oligosaccha-ride mixtures.