PHYSIOLOGICAL ADAPTATION AND PHYTOREMEDIATION POTENTIAL OF A HALOPHYTE, SESUVIUM PORTULACASTRUM UNDER HOSPITAL WASTEWATER EXPOSURE

Abstract

Hospital wastewater (HWW) poses a serious challenge to environmental cleanup owing to its complex nature, and the presence of pharmaceutical residues, microorganisms, and cytotoxic chemicals. In this study, we assessed the phytoremediation capacity of the halophyte Sesuvium portulacastrum (L.) L. in a 24-day hydroponic experiment at 5% HWW concentration, extending our research on this plant species in industrial wastewater situations. Physicochemical profile showed significant reductions in parameters: BOD decreased by 56.9%, COD by 77.2%, TSS by 87.6%, and TDS by 60.10%. The plant's biochemical response was biphasic: total phenolic content increased slightly on Day 8 before declining to 8.40 mg GAE g⁻¹ by Day 24, whereas total flavonoid content progressively increased to 108.13 µg QE g⁻¹FW, indicating a shift towards flavonoid-driven antioxidant defence over time. DPPH radical scavenging activity decreased to 62.3% on Day 8 before increasing to 79.2% on Day 24, indicating physiological adaptation of Sesuvium plants to the wastewater exposure. Phytotoxicity testing with Vigna radiata seeds showed significantly better germination and seedling development in the treated HWW than untreated HWW. These laboratory-scale results indicate that S. portulacastrum is a low-cost, environmentally friendly alternative for hospital wastewater treatment.