Abstrakt: |
It was supposed that the solubility of (l→4)(l→6)-linked α-d-glucans, e.g., glycogen, phytoglycogen, and amylopectin, in water was related to the colloidal dispersion stability of such molecules and depended on the degree of branching. Since phytoglycogen has various degrees of branching according to the maturation of plant seeds, it was extracted from sweet corn kernels at several days after pollination (DAP), and we have investigated the effects of the degree of branching on the dispersion stability of phytoglycogen (DSP) by salting out, using ammonium sulfate ((NH4)2SO4).As the sweet corn kernels matured, the concentration of (NH4)2SO4needed for salting out of phytoglycogen increased. According to the degree of branching measured by periodate oxidation analysis and β-amylolysis, the fraction of phytoglycogen precipitated at the high concentration with (NH4)2SO4has a highly branched structure. The turbidity of phytoglycogen aqueous solution was also measured to discuss the relation between the dispersion stability of colloidal particles and the degree of branching. We found that the variation of the degree of branching is closely related to DSP in an aqueous solution. |