Differential effects of acetophenone on shoots' and roots' metabolism of Solanum nigrum L. plants and implications in its phytoremediation

The wide ranges of uses for acetophenone make it more available and expected to accumulate in the biosphere, where consequently it can threat ecosystems. To remediate this problem, the use of Solanum nigrum L. plants for the clean-up of acetophenone-contaminated sites was explored. Also, plant root and shoot biometry and metabolism where assayed to better understand the effects of this organic compound and to pinpoint possible metabolic pathways to be targeted for future manipulations for increasing this plant species' remediation efficiency. Although undergoing through some stress, detected by increases in ROS and lipid peroxidation in both organs, plants were able to rapidly eliminate all acetophenone from the nutrient solution after 7 days of exposure, being this compound mainly detoxified at the root level. Additionally, acetophenone lead to a differential metabolic response in roots and shoots, where antioxidant mechanisms where differentially activated, while nitrogen assimilation was repressed in shoots and activated in roots. These results confirm that S. nigrum is a good phytoremediation tool for acetophenone and suggest that enhancing shoot GS activity may provide more nitrogen precursors for the synthesis of thiolated proteins and glutathione to increase tolerance to acetophenone in roots and shoots, respectively.