Jasmonic acid regulating glucosinolates-myrosinase system of cabbage sprouts

摘要

Isothiocyanates (ITCs) are a series components and have functions of anticancer, and antioxidant capacity. They are produced from glucosinolates (GLs) by the catalysis of myrosinase (MYR) when tissues or cells of Brassica vegetables are disrupted. In this study, the effects of jasmonic acid (JA) on GLs-MYR system in cabbage sprouts were investigated. The results showed that JA significantly inhibited the growth of cabbage sprouts and reduced their biomass. However, it effectively increased the GLs content, especially indole GLs glucobrassicin (GBC) and neoglucobrassicin (NGB). Under JA treatment, only 100 mol L-1 of JA increased the ITCs formation in cabbage sprouts through increasing the gene expression and activity of MYR. It was also found that cotyledon of cabbage sprouts contained the highest level of total GLs, aromatic GLs and indole GLs especially GBC and NGB, as well as the ITCs formation either in control or in JA treated sprouts. During the growth period, JA could effectively restrain the decrease of GLs content especially for the indole GLs induding GBC and NGB, it also enhanced MYR activity and gene expression for GLs synthesis and ITC formation. JA treatment altered the GLs composition and increased the relative content of indole GLs including GBC and NGB. The 100 mmol of JA was beneficial for increasing gene expression of GLs synthesis and ITCs formation so that it promoted the GLs-MYR system in cabbage sprouts.