Plant Quality and Food Security, Leibniz Institute of Vegetable and Ornamental Crops (IGZ) e.V., Theodor-Echtermeyer-Weg 1, 14979 Grossbeeren, Germany.
Hamburg School of Food Science, Universität Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
J Agric Food Chem. 2023 Aug 2;71(30):11466-11475. doi: 10.1021/acs.jafc.3c01997. Epub 2023 Jul 18.
The health-beneficial effects of vegetables are mainly attributed to their high contents of glucosinolates and the products of their hydrolysis, especially isothiocyanates. Distribution of glucosinolates across plant organs can strongly vary. Here, we investigated the effect of leaf age on glucosinolate accumulation and hydrolysis in two leafy vegetables, pak choi and giant red mustard. We also evaluated the activity of the hydrolyzing enzyme myrosinase across the leaves. Finally, we assessed whether glucosinolates are transported from older leaves to younger leaves. Young leaves of both species contained more than 3-fold more glucosinolates than older ones. Accordingly, more isothiocyanates were released in the young leaves. Myrosinases fully hydrolyzed all of the amounts of glucosinolates regardless of the leaf age. Moreover, older leaves were observed to supply younger leaves with glucosinolates. Thus, this study suggests that consumers can improve the nutritional value of food by incorporating young leaves of leafy in their diet.
蔬菜的有益健康作用主要归因于其较高含量的硫代葡萄糖苷及其水解产物，尤其是异硫氰酸酯。硫代葡萄糖苷在植物器官中的分布差异很大。在这里，我们研究了叶片年龄对两种绿叶蔬菜，白菜和芥菜中硫代葡萄糖苷积累和水解的影响。我们还评估了水解酶黑芥子酶在叶片中的活性。最后，我们评估了硫代葡萄糖苷是否从较老的叶片运输到较年轻的叶片。两种植物的幼叶中硫代葡萄糖苷的含量是老叶的 3 倍以上。相应地，幼叶中释放出更多的异硫氰酸酯。黑芥子酶完全水解了所有的硫代葡萄糖苷，而与叶片年龄无关。此外，观察到较老的叶片向较年轻的叶片提供硫代葡萄糖苷。因此，这项研究表明，消费者可以通过在饮食中加入绿叶蔬菜的幼叶来提高食物的营养价值。
