Uptake and mobilization of heavy metals through phytoremediation process from native plants species growing on complex pollutants: Antioxidant enzymes and photosynthetic pigments response

The aim of this work was to study the metal removal efficiency of Rumex dentatus, Ranunculus sceleratus, and Cammelina benghalensis which thrive on wastewater containing complex co-pollutants. Physico-chemical characteristic of wastewater showed high levels of biological oxygen demand (7136 mg kg ⁻¹), chemical oxygen demand (26324 mg kg ⁻¹), electric conductivity (1531 μS cm ⁻¹), along with metals (mg kg ⁻¹) such as Fe (124.65 mg kg ⁻¹), Zn (56.33 mg kg ⁻¹), Cu (6.34 mg kg ⁻¹), Cd (9.02 mg kg ⁻¹), Mn (23.64 mg kg ⁻¹), Ni (6.04 mg kg ⁻¹), Pb (1.20 mg kg ⁻¹), Hg (1.08 mg kg ⁻¹), Cr (1.31 mg kg ⁻¹) and As (1.43 mg kg ⁻¹) along with complex co-pollutants. All three plants reduced more than <50% of all physicochemical parameters and metal concentrations in wastewater. The chlorophyll (Ch-a, Chl-b) contents was highest in Rumex dentatus (5.03–6.74 mg g⁻¹ fw), followed by Ranunculus sceleratus (5.69.00–8.03 mg g⁻¹ fw), and Cammelina benghalensis (4.65–7.08 mg g⁻¹ fw), which showed the potentiality of plants. All the plants showed antioxidant activity (U/mL), i.e., superoxide dismutase (SOD), estimate peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), and hydrogen peroxidase (H₂O₂), bioaccumulation factor, and translocation factor, which demonstrated these plants’ high translocation abilities. The results offered evidence to support the potential of using native plants for phytoremediation as a novel green process to be integrated into the treatment and management of hazardous industrial wastewater.