Potential of Silver Nanoparticles in Phytoremediation of Wastewater and Their Effects on Growth Parameters of Brassica campestris L.

Abstract

Innovative solutions that should be researched include using nanoparticles and plants to regenerate heavy metal-polluted water and soil effectively. Silver nanoparticles (AgNPs) synthesized and characterized from Dryopteris filix were employed in phytoremediation. Wastewater was collected from sewage water canals on the boundaries of Abdul Wali Khan University Mardan Garden Campus. There were 19 distinct physicochemical properties assessed. Hydroponic research was used to explore the effect of silver nanoparticles on plant growth, photosynthetic pigments, phytohormones, primary and secondary metabolites, antioxidant activity, CAT and POD, and chromium (Cr) accumulation in Brassica campestris L. In addition to the Cr-polluted medium supplemented with 50 mgL⁻¹ of AgNPs, seedlings were cultivated in wastewater. An atomic absorption spectrophotometer (SPECTRO AAS-4000) was utilized to examine chromium in plant tissues. AgNPs improved plant growth and increased photosynthetic pigments, mitigating the stress of Cr and wastewater, while Cr and wastewater significantly reduced the development of seedlings. Plant growth, secondary metabolites, and phytohormones were all suppressed by chromium at a concentration of 50 mg L⁻¹. Production of phenol, flavonoids, indole acetic acid, protein, and sugar was increased, whereas oxidative stress was decreased in seedlings exposed to AgNPs. Chromium increased in wastewater application (131.4 & 82.2 mg kg^-1), whereas it dropped in AgNP application (104.6 & 82.2 mgkg^-1) in B. campestris root and shoot. These findings show that using the correct concentration of AgNPs can help plants remove heavy metals from polluted water through nano-phytoremediation.