The conformation of oxidized scleroglucan (sclerox) was characterized
in water and in NaCl aqueous solution by means of small-angle X-ray sc
attering (SAXS). The observed SAXS profiles were analyzed in terms of
a modified broken rod model, where each rod component was replaced wit
h the molecular models of a triple-stranded helix and a single chain s
imulated by the Monte Carlo method. The electrostatic interaction due
to carboxylate groups was taken into account by assuming a Gaussian-ty
pe interaction potential. The results confirmed that the triple-strand
ed helix of scleroglucan was disentangled to a single chain by the oxi
dation of beta-D-glucosyl side residues, The triple-stranded structure
is partly recovered by shielding charge on the side chains.