Copper Phthalocyanine Sulfonate-mediated Oxidative Degradation of 3-Hydroxyamino-1-methyl-5H-pyrido [4,3-b]indole [Trp-P-2(NHOH)], a Direct-acting Mutagen Derived from Trp-P-2 by Metabolic Activation

Abstract

Blue rayon and blue chitin are potential absorbents of heterocyclic amines. However, in our preliminary research, no recovery (0%) of an activated form of Trp-P-2, 3-hydroxyamino-1-methyl-5H-pyrido[4,3-b]indole [Trp-P-2 (NHOH)] with blue rayon extraction was observed. We investigated whether copper phthalocyanine sulfonate on blue rayon may react with Trp-P-2(NHOH) and accelerate the degradation of Trp-P-2(NHOH) in concert with oxygen and photons. Both the disulfonate and tetrasulfonate of copper phthalocyanine inhibited the mutagenicity of Trp-P-2(NHOH). Copper phthalocyanine disulfonate (CuCYB) accelerated the disappearance of Trp-P-2(NHOH). The degradation of Trp-P-2(NHOH) with CuCYB was attenuated in the presence of glutathione, under dark conditions, and with helium bubbling. Therefore, the reaction mechanisms may involve the interaction of molecular oxygen with CuCYB, which accelerate the oxidative degradation of Trp-P-2(NHOH). Photodynamic activation of molecular oxygen might contribute, in a part, to the oxidative degradation of Trp-P-2(NHOH).