Structural characterisation of a complex heteroglycan from the cyanobacterium Nostoc commune

► A complex high MW heteroglycan was isolated from the cyanobacterium Nostoc commune. ► Nc-5-s is composed of eleven different monosaccharidesincluding both acidic and OMe-units. ► Detailed structural characterisation of Nc-5-s using NMR spectroscopy. ► The results provide crucial data for future studies of cyanobacterial polysaccharides.