摘要：2, 7-Diaminophenazine (2, 7-diNH2-Pz) formed from m-phenylenediamine (PD) by hydrogen peroxide (H2O2) oxidation was extremely mutagenic in Salmonella typhimurium strain TA98 with a mammalian metabolic activation system (S9 mix). In order to evaluate the modulating effect of phenol derivatives and iron (II) sulfate on H2O2 oxidation of m-PD, m-PD and mixtures of m-PD and phenol derivatives (m-PD/phenols) were treated with 3% H2O2 in the presence or absence of iron (II) sulfate and their mutagenicity was tested using strain TA98 with S9 mix. The total mutagenicity, which was calculated from the yields of oxidized mixtures (i.e. ethyl acetate extract) and their mutagenicity, decreased remarkably by the addition of iron (II) sulfate into the H2O2 oxidation system. Since the yields of 2, 7-diNH2-Pz and ethyl acetate extract decreased more in a H2O2-iron (II) sulfate oxidation system than those in a H2O2 oxidation system, the reduction of the total mutagenicity was presumed to be due to the accelerated polymerization of m-PD by iron (II) sulfate added. Furthermore, the modulating effect of 5 kinds of metal chelates on the mutagenicity of 2, 7-diNH2-Pz and on the H2O2 oxidation of m-PD was evaluated. All tested metal chelates reduced the mutagenic response of 2, 7-diNH2-Pz in strain TA98 with S9 mix, and the strongest inhibitory effect was observed in the case using hemin. The amount of free 2, 7-diNH2-Pz in the mixture solution of 2, 7-diNH2-Pz and metal chelates was correlated to the mutagenic potency of the mixture. It was suggested that the mutagenic inhibitory effect of metal chelates depend on the complex formation of metal chelates with 2, 7-diNH2-Pz. The addition of metal chelates into the H2O2 oxidation system of m-PD significantly decreased the amount of free 2, 7-diNH2-Pz in the reaction mixture. The reduction of the yield of 2, 7-diNH2-Pz was assumed to be based on the polymerization of m-PD by metal chelates as catalyst and formation of complex with 2, 7-diNH2-Pz and metal chelates.
关键词：2, 7-diaminophenazine;Salmonella typhimurium TA98;oxidation;m-phenylenediamine;phenol derivative;iron (II) sulfate;metal chelate;mutagenicity
