Green synthesis of magnetic silver/zinc/iron nanocomposite mitigates detrimental effects of polymethyl methacrylate nanoplastics and Arsenic and ameliorates biochemical compositions in Triticum aestivum L

With the phytotoxicity of nano-microplastics and heavy metals, it becomes imperative to develop appropriate solutions to prevent the entry of these pollutants into plants and to mitigate their harmful effects. The silver/zinc/iron green magnetic nanocomposite (Ag/Zn/Fe) was synthesized using Malva Sylvestris plant extract and characterized by TEM, XRD, FESEM. To explore the effects of Arsenic (As: 50 or 100 mg/L), polymethyl methacrylate nanoplastics (PMMANPs: 50 or 500 mg/L), and Ag/Zn/Fe (100 mg/L) in the wheat plant medium, a factorial experiment employing a randomized complete block design was conducted. TEM images showed the presence of PMMANPs in the roots and leaves, and Ag/Zn/Fe in the leaves. The results indicated that PMMANPs and Ag/Zn/Fe reduced As absorption into the plants. Both As and PMMANPs increased total phenol content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity. They also increased hydrogen peroxide (H2O2) and malondialdehyde (MDA) content. Ag/Zn/Fe improved wheat tolerance by reducing MDA and H2O2, TPC and TFC under As and PMMANPs. Polyphenol profile of leaves was changed by all treatments. As increased cinnamic acid, caffeic acid, gallic acid, chlorogenic acid, and p-coumaric, and As+PMMANPs enhanced rosmarinic acid, quercetin and chlorogenic acid. Ag/Zn/Fe increased gallic acid and chlorogenic acid in non-stressed treatments, rosmarinic acid and chlorogenic at 50 mg/L As, and quercetin and caffeic acid at 100 mg/L As. These results suggest that Ag/Zn/Fe mitigated the adverse effects of As and PMMANPs in wheat plants.