Phytoextraction, accumulation, and toxicological effects of 1-tetradecyl-3-methylimidazolium ionic liquid in ryegrass (Lolium perenne L.).

Ionic liquids are widely used in many fields due to their extremely tunable nature and exceptional properties. The extensive application of ionic liquids raises great concerns regarding their bioaccumulation potential and adverse effects on organisms. Green plants have a great potential for uptake of persistent xenobiotics from aquatic and terrestrial environment. However, the assimilation and bioaccumulation of 1-tetradecyl-3-methylimidazolium bromide ([C14mim]Br) have not been studied in plants yet. In order to explore the phytoaccumulation of [C14mim]+, ryegrass were exposed to [C14mim]Br with hydroponic experiment. The effects of [C14mim]Br dosages on growth index, chlorophyll content, malondialdehyde (MDA) content, and antioxidant enzyme activity of ryegrass were investigated. The toxic effects of [C14mim]Br on ryegrass growth increased with increasing initial concentration. The high initial concentration treatment resulted in rapid changes in physiological characteristics in ryegrass tissue. [C14mim]+ ions were mainly accumulated in root tissue and partly translocated to the above ground part of ryegrass. [C14mim]+ was observed in the highest concentration (314.35 μg/g in root and 101.42 μg/g in aboveground parts of ryegrass) with 10 mg/L of [C14mim]Br. Our results demonstrated that ryegrass can uptake and accumulate [C14mim]+ and is therefore a suitable species for phytoremediation of trace amount of [C14mim]+ and possibly other ionic liquids.