Identification of high β-glucan oat lines and localization and chemical characterization of their seed kernel β-glucans

Oat, (Avena sativa) is an excellent source of mixed linkage β-glucans ((1 → 3)(1 → 4)-β-d-glucan), a dietary fibre with cholesterol lowering properties. Using a mutagenized oat-population we screened 1700 different lines and identified ten lines that displayed β-glucan levels above 6.7% and 10 below 3.6%. The extreme values were 1.8% and 7.5%. We chose six lines with an increased- and four lines with a reduced β-glucan content for further study. By longitudinal- and cross-sections of seeds it was shown that localization of β-glucan varied between the different lines. In addition, β-glucan quality parameters like molecular weight and solubility were also determined. Although the selection was designed for quantitative differences, qualitative differences between the β-glucans from the different lines were found. The high and low β-glucan lines will now be used as a model system to study molecular regulation of β-glucan biosynthesis as well as possible links between fibre quality and biological activity.