STRUCTURE OF TOTAL BARLEY BETA-GLUCAN

The fine structure of total barley beta-glucan, as extracted by hot perchloric acid, was investigated by partial enzymatic hydrolysis. Molecular weight profiles of the resulting oligomeric products were similar to those from hydrolysed 40-degrees-C water-soluble beta-glucan. Concentrations of individual oligosaccharides from total beta-glucan were found to vary between oats and barley and among barley varieties, suggesting variability in beta-glucan structure. Methylation studies, using HPLC to separate methylated sugars, showed no evidence for the presence of contiguous beta-1,3 links in total barley beta-glucan, although not all fractions of total beta-glucan were analysed.