Effect of Zinc Sulphate Treatments on Key Active Components and the Molecular Mechanism of Thioglycoside Changes of Broccoli Sprouts

To investigated the effects of spray application of zinc sulfate (ZnSO4) solution on the accumulation of crucial bioactive components and antioxidant activity, and explored the regulatory mechanism of zinc sulfate on glucosinolates in broccoli flower buds and seedlings at the molecular level, seven-day-old broccoli sprouts were treated with one of four concentrations (1, 2, 4, and 8 mmol/L) of aqueous ZnSO4 solutions or water (0 mmol/L ZnSO4 as the control). The effects of each ZnSO4 treatment on the bioactive components of broccoli sprouts were investigated by determining the contents of chlorophyll, ascorbic acid, total flavonoids, total phenols, and total glucosinolates, as well as myrosinase activity and DPPH free-radical scavenging rate. The expression levels of glucosinolate synthesis structural genes in the sprouts were analyzed using a real-time quantitative PCR detection system. The results showed that the chlorophyll content of all ZnSO4 treatments was lower than that of the control. The ascorbic ac