Binding of mineral elements by some dietary fibre components— In vitro (II)

Abstract

The ability of some fibre preparations (soluble fibre fractions of wheat bran and whole-grain wheat bread-dough, a bulk-laxative—Inolaxol—and cellulose) to bind copper (II), zinc(II) and cadmium(II) ions has been studied using a potentiometric method. Soluble fibre fractions of wheat bran and whole-grain wheat bread-dough, in which most of the phytate was present, interacted strongly with the metal ions. Incubation of these fractions with phytase reduced the complexing ability, indicating the active ligand to be phytate. Inolaxol (a bulk laxative containing about 80% Sterculia gum) also bound a considerable amount of the three metals, which could not be explained by the Sterculia gum itself. The complexing ability of cellulose was negligible.