Lüthy J, Carden B, Friederich U, Bachmann M
Experientia. 1984 May 15;40(5):452-3. doi: 10.1007/BF01952381.
N-nitrosamides are known as direct-acting carcinogens at the site of their formation; they do not need any metabolic activation in vivo. The conditions leading to their formation in the stomach, and also their genotoxicity, have been thoroughly studied with some model compounds. Several reports link this type of compound to the induction of gastric cancer in human. However, only limited data are presently available about possible precursors of N-nitrosamides in foods. In the present study we found that goitrin --a naturally occurring compound in cruciferous vegetables and rape--could be easily nitrosated by treatment with nitrite under stomach conditions, yielding with loss of sulfur the N-nitroso- oxazolidone 4 (fig.). This product has a mutagenicity pattern and potency similar to that of N-nitroso-N-methyl-N'- nitroguanidine (MNNG) in the Ames Salmonella/mammalian microsome test.
N-亚硝基酰胺在其形成部位被认为是直接作用的致癌物；它们在体内不需要任何代谢激活。已经用一些模型化合物对导致它们在胃中形成的条件及其遗传毒性进行了深入研究。几份报告将这类化合物与人类胃癌的诱发联系起来。然而，目前关于食物中N-亚硝基酰胺可能的前体的可用数据有限。在本研究中，我们发现甲状腺肿素——十字花科蔬菜和油菜中的一种天然存在的化合物——在胃部条件下用亚硝酸盐处理很容易被亚硝化，失去硫后生成N-亚硝基-恶唑烷-4（图）。在艾姆斯沙门氏菌/哺乳动物微粒体试验中，该产物的诱变性模式和效力与N-亚硝基-N-甲基-N'-硝基胍（MNNG）相似。
