Study on antimutagenicity of the agents related to foods

1)我们从对风味的研究中得出了一个理论，即抗突变剂必须与突变剂一样通过rec-assay检测。为了验证这一理论，本文采用艾姆斯试验和再试验对20多种天然食品添加剂进行了致突变性检测。2）采用沸水浸提法对几种茶叶进行抗突变性研究。日本茶具有较强的抗突变性，而乌龙茶和普洱茶则没有。提取物的HPLC分级分离实验表明，抗突变作用不是由于咖啡因或咖啡因。结果表明，提取物对细菌无毒性作用，再试验也无效。3）丙氨酸和葡萄糖的美拉德反应增强了AF-2的致突变性，而降低了MNNG的致突变性。4）对12种有机砷化合物的致突变性和抗突变性进行了研究。其中2株在rec-assay中呈阳性反应，在艾姆斯试验中均无致突变性。Seven诱导CHL细胞SCE。5）汞蒸气灯照射可明显降低大多数典型诱变剂的致突变性。而染发剂中间体4-硝基邻苯二胺的诱变性则随照射量的增加而增加。6）降低预孵育液中二甲基亚砜的浓度，可增强1-硝基芘的致突变性。这种增强似乎是由于细胞壁对化学物质的吸收增加。这一现象在难溶于水的化学品中很常见。本实验提示了一种新型的抗突变作用。

1) We had had a theory from the study on flavors that antimutagens must be detected by the rec-assay as well as mutagens. To prove the theory, mutagenicity of over 20 natural food additives were surveyed by Ames test and the rec-assay. They, however, did not show toxicity on the bacteria and so the rec-assay was not useful.2) Several kinds of tea leaves were extracted with boiling water and antimutagenicity of the extracts were surveyed. Japanese tea had strong antimutagenicity but Oolong tea or Puar tea did not have. The experiments of fractionation of the extract with HPLC suggested that antimutagenicity was not due to catekins or caffeins. The extracts showd no toxicity on the bacteria, and the rec-assay was not useful, too.3) We found that the Maillard reactive of alanine and glucose enhanced the mutagenicity of AF-2 and decreased that of MNNG. The mechanism was not cleared.4) Mutagenicity and antimutagenicity of 12 organoarsenic compounds were surveyed. Two of them were positive in the rec-assay and all of them were not mutagenic in Ames assay. Seven induced SCE in CHL cells. Three reduced the mutagenicity of quercetin.5) The mutagenicity of most of typical mutagens decreased strongly by irradiation of a mercury vapour lamp. However, that of 4-nitro-o-phenylenediamine, an intermediate of hair dyes, increased lineally with irradiation.6) We found that the mutagenicity of 1-nitropyrene was enhanced byreducing the concentration of dimethylsulfoxide in the preincubation mixture. The enhancement seemed to be due to increased absorption of the chemicals by the cell walls. This phenomenon were common to the chemicals hardly soluble in water. This experiment suggested a new type of antimutagenicity.