Structural and biological characterization of sulfated-derivatized oat beta-glucan

Abstract

The structural, physicochemical, and biological properties of sulfated oat beta-glucan were characterized. The degree of substitution of the sulfated oat-beta glucan was obtained by elemental analysis, which was 0.68. Compared to native oat beta-glucan, the FT-IR spectra of the derivative showed two new absorption bands at 1250 and 810 cm(-1), which would be attributed to (S = O) and (C-O-S) groups, respectively. The molecular weight of the sulfated beta-glucan was determined to be 68 kDa and its viscosity decreased by almost 2 orders of magnitude while its solubility increased by more than 100% compared to that of the native beta-glucan. In addition, the sulfation caused the reduction of in vitro bile acid binding capacity of oat beta-glucan due to the new anionic character and decreased molecular weight. The sulfated derivative exhibited, however, anticoagulant activity which showed a concentration-dependent increase.