Lee Jeong Gu, Lim Sooyeon, Kim Jongkee, Lee Eun Jin
Department of Plant Science, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
Department of Integrative Plant Science, Chung-Ang University, Anseong 456-756, Republic of Korea.
Food Chem. 2017 Oct 15;233:60-68. doi: 10.1016/j.foodchem.2017.04.104. Epub 2017 Apr 19.
The hydrolysis of glucosinolates (GSLs) by myrosinase yields varieties of degradation products including isothiocyanates (ITCs). This process is controlled by the glucosinolate-myrosinase (G-M) system. The major ITCs in radish roots are raphasatin and sulforaphene (SFE), and the levels of these compounds decrease during storage after harvest. We investigated the G-M system to understand the mechanism behind the decrease in the ITCs in radish roots. Six varieties of radish roots were stored for 8weeks at 0-1.5°C. The concentrations of GSLs (glucoraphasatin and glucoraphenin) were maintained at harvest levels without significant changes during the storage period. However, SFE concentration and myrosinase activity remarkably decreased for 8weeks. Pearson correlation analysis between ITCs, GSLs, and myrosinase activity showed that a decrease of SFE during storage had a positive correlation with a decrease in myrosinase activity, which resulted from a decrease of ascorbic acid but also a decrease of myrosinase activity-related gene expressions.
芥子酶催化硫代葡萄糖苷（GSLs）水解产生包括异硫氰酸盐（ITCs）在内的多种降解产物。这一过程受硫代葡萄糖苷 - 芥子酶（G - M）系统控制。萝卜根中的主要ITCs是莱菔硫烷素和萝卜硫素（SFE），这些化合物的含量在收获后的储存过程中会降低。我们研究了G - M系统，以了解萝卜根中ITCs含量降低背后的机制。六个品种的萝卜根在0 - 1.5°C下储存8周。硫代葡萄糖苷（葡萄糖莱菔硫素和葡萄糖萝卜硫素）的浓度在储存期间保持在收获时的水平，没有显著变化。然而，SFE浓度和芥子酶活性在8周内显著下降。ITCs、GSLs和芥子酶活性之间的Pearson相关性分析表明，储存期间SFE的降低与芥子酶活性的降低呈正相关，这是由于抗坏血酸的减少以及与芥子酶活性相关的基因表达的降低所致。
