Tawfiq N, Heaney R K, Plumb J A, Fenwick G R, Musk S R, Williamson G
Food Molecular Biochemistry Department, Institute of Food Research, Norwich Research Park, Colney, UK.
Carcinogenesis. 1995 May;16(5):1191-4. doi: 10.1093/carcin/16.5.1191.
We have tested the ability of a representative range of dietary glucosinolates and their breakdown products, found in high concentrations in cruciferous vegetables, to act as blocking agents against carcinogenesis by inducing the activity of the anticarcinogenic phase II marker enzyme quinone reductase in murine hepa1c1c7 cells. Breakdown of glucosinolates was catalysed by the endogenous plant enzyme thioglucoside glucohydrolase at neutral and acid pH. Only two unmodified glucosinolates, p-hydroxybenzyl and 2-hydroxybut-3-enyl, significantly induced quinone reductase activity. However, after enzymic hydrolysis at near-neutral pH, some of the glucosinolates yielded breakdown products that significantly induced quinone reductase in the order: 3-methylsulphinylpropyl-->prop-2-enyl-->pent-4-enyl approximately 2-phenylethyl approximately benzyl-->all others tested. Incubation with myrosinase at acidic pH resulted in induction of quinone reductase activity by the hydrolysis products of only three of the tested glucosinolates:3-methylsulphinyl-propyl approximately 2-phenylethyl-->benzyl-->all others, activity due to the two alkenyl compounds being lost. The results show that the potential cancer-blocking action of both intact and thioglucoside glucohydrolase-treated glucosinolates, as assessed by induction of phase II enzyme activity, is dependent on the nature of the side chain of the parent glucosinolate.
我们检测了一系列具有代表性的膳食硫代葡萄糖苷及其分解产物（在十字花科蔬菜中含量很高）作为阻断剂预防癌变的能力，这些硫代葡萄糖苷及其分解产物可通过诱导鼠hepa1c1c7细胞中抗癌II相标志物酶醌还原酶的活性来发挥作用。硫代葡萄糖苷的分解由内源性植物酶硫代葡萄糖苷葡萄糖水解酶在中性和酸性pH条件下催化。只有两种未修饰的硫代葡萄糖苷，即对羟基苄基硫代葡萄糖苷和2-羟基丁-3-烯基硫代葡萄糖苷，能显著诱导醌还原酶活性。然而，在近中性pH条件下进行酶水解后，一些硫代葡萄糖苷产生的分解产物能显著诱导醌还原酶活性，其诱导顺序为：3-甲基亚磺酰丙基＞2-丙烯基＞4-戊烯基≈2-苯乙基≈苄基＞所有其他测试的产物。在酸性pH条件下与黑芥子酶一起孵育，仅三种测试硫代葡萄糖苷的水解产物能诱导醌还原酶活性：3-甲基亚磺酰丙基≈2-苯乙基＞苄基＞所有其他产物，由于两种烯基化合物导致的活性丧失。结果表明，通过II相酶活性诱导评估，完整的和经硫代葡萄糖苷葡萄糖水解酶处理的硫代葡萄糖苷的潜在抗癌作用取决于母体硫代葡萄糖苷侧链的性质。
