The D-Mannitol assay will only measure the free, non-covalently linked monosaccharide.  Oligosaccharides or polysaccharides can be measured after hydrolysis to free monosaccharides.  Generally acid hydrolysis can be achieved by boiling the oligo/polysaccharide in 1.3 M HCl for 1 h.  It is recommended that scientific literature is consulted for information on hydrolysis conditions for the particular oligo/polysaccharide that is being measured.

Product Page (K-MANOL)