Preharvest Methyl Jasmonate Treatment Increased Glucosinolate Biosynthesis, Sulforaphane Accumulation, and Antioxidant Activity of Broccoli.

Broccoli is becoming increasingly popular among consumers owing to its nutritional value and rich bioactive compounds, such glucosinolates (GSLs) and hydrolysis products, which are secondary metabolites for plant defense, cancer prevention, and higher antioxidant activity for humans. In this study, 40 μmol/L methyl jasmonate (MeJA) was sprayed onto broccoli from budding until harvest. The harvested broccoli florets, stem, and leaves were used to measure the contents of GSLs, sulforaphane, total phenolics, and flavonoids, as well as myrosinase activity, antioxidant activity, and gene expression involved in GSL biosynthesis.

Effects of LED illumination spectra on glucosinolate and sulforaphane accumulation in broccoli seedlings.

Glucosinolates (GSLs) are well known for plant defense and human nutrition. In this study, broccoli seedlings were illuminated under different LED light, including white, red, blue, and 75% red + 25% blue (200 mmol·m·s) for 4 weeks to investigate the effects of LED light on GSLs and sulforaphane biosynthesis. Results showed that red light promoted GSL biosynthesis and sulforaphane accumulation because red light could induce SOT18 expression to advance aliphatic GSLs biosynthesis, whereas the high tryptophan content and the upregulation of CYP79B2, CYP79B3, and CYP83B1 were attributed to indole GSL biosynthesis.

Effect of selenium-sulfur interaction on the anabolism of sulforaphane in broccoli.

The effects of S (as sulphate) and Se (as selenite) treatment (S mM/Se μM: 1/0, 1/50, 1/100, 1/150, 4/0, 4/50, 4/100, and 4/150) on the production of sulforaphane (an anticancer compound), the accumulation of its precursor substance, and the expression of genes related to glucoraphanin biosynthesis in broccoli were examined. Sulforaphane yield and myrosinase activity increased significantly with the combined application of 4 mM S and 100 μM Se on broccoli. Furthermore, the concentrations of glucoraphanin (a sulforaphane precursor) and methionine (a glucoraphanin substrate) slightly changed after Se application.

Comparative transcriptome analyses of genes involved in sulforaphane metabolism at different treatment in Chinese kale using full-length transcriptome sequencing.

Background: Sulforaphane is a natural isothiocyanate available from cruciferous vegetables with multiple characteristics including antioxidant, antitumor and anti-inflammatory effect. Single-molecule real-time (SMRT) sequencing has been used for long-read de novo assembly of plant genome. Here, we investigated the molecular mechanism related to glucosinolates biosynthesis in Chinese kale using combined NGS and SMRT sequencing.