The degree of acetylation (DA) of various samples has been evaluated by H-1
liquid-state NMR and C-13 and N-15 CP-MAS solid-state NMR over the whole r
ange of DA. A good agreement has been found for all the experiments. The C-
13 and N-15 CP-MAS experiments have permitted the evaluation of the chitin
DA and content in the structural polysaccharides in a fungus named Aspergil
lus niger. The fungus structural carbohydrates mainly consist in pure chiti
n associated with glucans. Comparison of the C-13 CP-MAS spectra with stand
ard (1-->3)-beta -D-glucans strongly suggests that chitin and glucans are l
inked via covalent bonds.