Physicochemical properties and physiological effects of the (1----3)(1----4)-beta-D-glucan from oats.

In summary, despite the many uncertainties regarding mode of action, these results have established that the soluble dietary fibre from oats, mainly (1----3)(1----4)-beta-D-glucan, is physiologically active in a fashion similar to guar gum. Extraction processes reduce the molecular size of the beta-glucan relative to the native cell wall polymer, and the product was of lower viscosity than a guar gum used for comparison, but this did not appear to affect either in vivo or in vitro activity under the conditions used. There remains a need to develop a clearer picture of the relationship, if any, of viscosity to activity, through dose response studies with products of different viscosity.