Abstract:
Variations in the concentration of glucoraphanin (GRA) and glucoerucin (GER), as well as the corresponding breakdown products, isothiocyanates (ITCs) and nitriles, were investigated during the growth of broccoli sprouts. The concentrations of GRA and GER decreased sharply from 33.66 µmol/g to 11.48 µmol/g and 12.98 µmol/g to 8.23 µmol/g, respectively, after seed germination. From the third to the seventh day, both GRA and GER were maintained as relatively stable. The highest concentrations of sulforaphane (17.16 µmol/g) and erucin (12.26 µmol/g) were observed on the first day. Hereafter, the concentrations of nitrile hydrolyzed from GRA or GER were higher than those of the corresponding ITCs. Moreover, the ratio of sulforaphane to sulforaphane nitrile decreased from 1.35 to 0.164 from 1 d to 5 d, with a similar trend exhibited for erucin/erucin nitrile after 2 d. RNA-seq analysis showed that BolMYB28 and BolCYP83A1, involved in aliphatic glucosinolate (GSL) biosynthesis, remained largely unexpressed until the third day. In contrast, the genes operating within the GSL-myrosinase hydrolysis pathway were highly expressed right from the beginning, with their expression levels increasing significantly after the third day. Additionally, we identified two BolESPs and six BolNSPs that might play important roles in promoting the production of nitriles during the development of broccoli sprouts.
摘要:
葡萄糖苷(GRA)和芥酸葡萄糖苷(GER)的浓度变化,以及相应的细分产品,异硫氰酸酯(ITC)和腈,在西兰花芽的生长过程中进行了调查。GRA和GER的浓度从33.66μmol/g急剧下降至11.48μmol/g,从12.98μmol/g急剧下降至8.23μmol/g,分别,种子发芽后。从第三天到第七天,GRA和GER均维持相对稳定.第一天观察到最高浓度的萝卜硫烷(17.16µmol/g)和芥酸素(12.26µmol/g)。此后,从GRA或GER水解的腈浓度高于相应的ITC。此外,从1d到5d,萝卜硫烷与萝卜硫烷腈的比率从1.35下降到0.164,在2d后,芥酸素/芥酸素腈表现出类似的趋势。RNA-seq分析表明,BolMYB28和BolCYP83A1参与脂肪族芥子油苷(GSL)生物合成,基本上没有表达,直到第三天。相比之下,在GSL-黑芥子酶水解途径内运作的基因从一开始就高表达,其表达水平在第三天后显著增加。此外,我们确定了两种BolESP和六种BolNSP,它们可能在西兰花芽发育过程中促进腈的产生中起重要作用。