The role of secondary metabolites of Pontederia parviflora Alexander and Salvinia auriculata Aubl. in phytoremediation of cadmium contaminated water

Abstract Heavy metals represent a serious source of water and soil contamination, mainly due to their non-biodegradable nature. Their bioaccumulation occurs in plants and other trophic levels, including animals, consequently affecting humans and causing various side effects. Phytoremediation offers a biological, cost-effective, and environmentally friendly cleaning solution, utilizing plants to remove contaminants from soil and water. This study aims to establish the chemical composition of Pontederia parviflora and Salvinia auriculata using liquid chromatography and evaluate the role of their secondary metabolites in passive phytoremediation by these plants. Although the results are not aligned with the initial hypothesis of metal removal from the liquid medium (sequestration and chelation of metals), the amount of metal removed still represents a positive outlook for technique enhancement. Furthermore, this research challenges the notion presented in the literature, as secondary metabolites were considered contaminant sequesters. The removal of these metabolites from the biomass of these macrophytes did not significantly impact their phytoremediation performance.