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Abstract：
The mutagenic patterns of A. flavus, A. parasiticus and A. fumigatus extracts were evaluated. These strains of toxigenic Aspergillus were collected from the agricultural environment. The Ames test was performed on Salmonella typhimurium strains TA98, TA100 and TA102, without and with S9mix (exogenous metabolic activation system). These data were compared with the mutagenicity of the corresponding pure mycotoxins tested alone or in reconstituted mixtures with equivalent concentrations, in order to investigate the potential interactions between these molecules and/or other natural metabolites. At least 3 mechanisms are involved in the mutagenic response of these aflatoxins: firstly, the formation of AFB1-8,9-epoxide upon addition of S9mix, secondly the likely formation of oxidative damage as indicated by significant responses in TA102, and thirdly, a direct mutagenicity observed for higher doses of some extracts or associated mycotoxins, which does not therefore involve exogenously activated intermediates. Besides the identified mycotoxins (AFB1, AFB2 and AFM1), additional \"natural\" compounds contribute to the global mutagenicity of the extracts. On the other hand, AFB2 and AFM1 modulate negatively the mutagenicity of AFB1 when mixed in binary or tertiary mixtures. Thus, the evaluation of the mutagenicity of \"natural\" mixtures is an integrated parameter that better reflects the potential impact of exposure to toxigenic Aspergilli.
摘要：
黄曲霉的诱变模式，对寄生曲霉和烟曲霉提取物进行了评价。这些产毒素曲霉菌株是从农业环境中收集的。在没有和有S9mix（外源代谢活化系统）的情况下，对鼠伤寒沙门氏菌菌株TA98，TA100和TA102进行了Ames测试。将这些数据与单独测试的相应纯霉菌毒素或在等浓度的重组混合物中测试的致突变性进行比较，以研究这些分子和/或其他天然代谢物之间的潜在相互作用。至少有3种机制参与这些黄曲霉毒素的诱变反应：首先，添加S9mix后形成AFB1-8,9-环氧化物，第二，氧化损伤的可能形成，如TA102中的显著反应所示，第三，对高剂量的某些提取物或相关霉菌毒素观察到的直接诱变性，因此不涉及外源活化的中间体。除了确定的霉菌毒素（AFB1，AFB2和AFM1），额外的“天然”化合物有助于提取物的全球诱变性。另一方面,当在二元或三元混合物中混合时,AFB2和AFM1负调节AFB1的致突变性。因此，对“天然”混合物致突变性的评估是一个综合参数，可以更好地反映暴露于产毒曲霉的潜在影响。
