Comparison on the Nitrite Scavenging Activity and Antimutagen Formation between Insoluble and Soluble Dietary Fibers

Abstract

Nine insoluble fibers prepared from fruits and vegetables and eleven soluble fibers were evaluated for their nitrite scavenging activity and the antimutagen formation of aminopyrene-nitrite (AP-nitrite) model in the Ames test. Most of the insoluble fibers were good nitrite scavengers and inhibitors of mutagen which arose from the reaction of the model (pH 3). However, it was found that most of the soluble fibers were not good nitrite scavengers. The presence of some fibers (7 out of 11) in the reaction mixture of the AP-nitrite model increased the revertant number of Salmonella typhimurium TA98 and TA100 induced by the reaction products. Subsequent experiments showed that the binding of aminopyrene to some soluble fibers was reversible and might be the possible mechanism of mutagenic enhancement.