Pelroy R A, Petersen M R
Environ Health Perspect. 1979 Jun;30:191-203. doi: 10.1289/ehp.7930191.
Conditions that affect the sensitivity of the Ames assay of complex hydrocarbon mixtures derived from shale oil were studied. Two fractions, one enriched in polynuclear aromatic compounds (PNA fraction), and a second fraction enriched in aromatic and heterocyclic amines (basic fraction), were selected for most of this work because of their comparatively high mutagenicity (i.e., compared with raw shale oil). The crude shale oil, as well as the basic, PNA, and tar fractions were mutagenic against the Salmonella typhimurium test strains, TA98 and TA100. Mutation was dependent on metabolic activation by microsomal (S9) enzymes. Both test strains responded equally well to the crude product and to the basic fraction; however, strain TA100 was more effective than TA198 in demonstrating the mutagenicity of the PNA fraction. The mutagenicity of the tar fraction could be most easily detected after metabolic activation in a liquid medium, as opposed to S9 activation in the top agar of the standard Ames assay. The mutagenicity of the basic fraction or 2-aminoanthracene was also demonstrated by metabolic activation in a liquid medium. In other set of experiments, the effect of chemical composition on the expression of mutagenicity in the standard Ames assay was estimated. Premutagens requiring metabolic activation were added to the basic and PNA fractions, and the numbers of revertants obtained in the presence of the fractions were compared with mutation induced by the compounds alone. The basic fraction did not interfere with the mutagenicity of 2-aminoanthracene and 7,9 dimethylbenz[c]acridine. Moreover, in certain experiments, the mutagenicity of the complex fraction plus the added compound was higher than expected on the basis of assays performed on these materials separately. Conversely, the PNA fraction prevented or strongly inhibited mutation by several polynuclear aroumatic compounds, and an acridine. However, the PNA fraction did not inhibit mutation induced by 2-aminoanthracene. The effect of the basic fraction on stability of the S9 enzymes in the standard Ames test was also determined.
研究了影响源自页岩油的复杂烃混合物埃姆斯试验敏感性的条件。由于其相对较高的致突变性（即与未加工的页岩油相比），在这项工作的大部分实验中选用了两个馏分，一个富含多核芳香化合物（PNA馏分），另一个富含芳香胺和杂环胺（碱性馏分）。粗页岩油以及碱性、PNA和焦油馏分对鼠伤寒沙门氏菌测试菌株TA98和TA100具有致突变性。突变依赖于微粒体（S9）酶的代谢激活。两种测试菌株对粗产物和碱性馏分的反应同样良好；然而，在证明PNA馏分的致突变性方面，菌株TA100比TA198更有效。与标准埃姆斯试验顶层琼脂中的S9激活相反，焦油馏分的致突变性在液体培养基中经代谢激活后最容易检测到。碱性馏分或2-氨基蒽的致突变性也通过在液体培养基中的代谢激活得到证实。在另一组实验中，评估了化学成分对标准埃姆斯试验中致突变性表达的影响。将需要代谢激活的前诱变剂添加到碱性和PNA馏分中，并将在有馏分存在的情况下获得的回复突变体数量与单独化合物诱导的突变进行比较。碱性馏分不干扰2-氨基蒽和7,9-二甲基苯并[c]吖啶的致突变性。此外，在某些实验中，复合馏分加添加化合物的致突变性高于对这些材料单独进行试验所预期的结果。相反，PNA馏分可防止或强烈抑制几种多核芳香化合物和一种吖啶诱导的突变。然而，PNA馏分不抑制2-氨基蒽诱导的突变。还测定了碱性馏分对标准埃姆斯试验中S9酶稳定性的影响。
