Effects of iron and cupper ions on sulforaphane content and peroxidase activity in Lepidium draba seedlings

Sulforaphane (SFN) is an isothiocyanate which is produced through glucoraphanin hydrolysis via myrosinase activity. In the present study, SFN content and peroxidase activity has been assessed in treated Lepidium draba seedlings with different concentrations of iron and copper during ۸ and ۱۶ hours treatment. The results showed that the SFN content drastically elevated at treatment with ۱ mg/L Fe۲+ after ۸ hours treatment which was around two-fold compared to the control. But its content decreased in treated seedlings with higher Fe۲+ concentrations as well as treatment with all concentrations of Cu۲+. Furthermore, promotion of peroxidase activity was seen in the treated seedlings with the both elicitors. The data revealed that not only the inhibitory effect of Cu۲+ on SFN production was stronger than Fe۲+, but its stimulatory effect on peroxidase activity was also remarkable especially after ۱۶ hours treatment. It seems that the metals induce triggering of reactive oxygen species (ROS) which at low Fe۲+ concentration leads to induce glucoraphanin biosynthesis pathway. While at higher Fe۲+ concentrations as well as treatment seedlings with Cu۲+, ROS lead to induce antioxidant enzyme system.   https://dorl.net/dor/۲۰.۱۰۰۱.۱.۲۳۸۳۳۰۱۷.۲۰۱۴.۱.۱.۲.۱