Adsorption of mutagens in distilled water by dietary fibers

Dietary fibers, alginate and defatted corn fiber, adsorbed food mutagens, Trp-P-1 and Glu-P-1, which are heterocyclic amines formed in cooking processes. The saturation masses of adsorbed heterocyclic amines to unit mass of the alginate, and to the defatted corn fiber, in distilled water, were independent of the specific surface area of the dry fibers. The saturation mass of Trp-P-1 to the alginate was more than twenty times as much as that to the defatted corn fiber, binding of 0.8 mol, or more, of Trp-P-1 per 1 mol of uronic acid of alginate. Pectic acid, another polymer of uronic acid, also had high binding capacity for Trp-P-1 and Glu-P-1, but chitosan, a polymer of glucosamine, adsorbed neither Trp-P-1 nor Glu-P-1. Dimethylnitrosoamine, which is also a food mutagen, was not adsorbed to these dietary fibers. These results suggested that the heterocyclic amines were mostly adsorbed to the carboxyl groups of the dietary fibers.