Innovative N-butyryl-L-homoserine lactones-assisted strategy for phytoremediation: Improving soybean growth and soil quality in dimethyl phthalate remediation

The excessive accumulation of dimethyl phthalate (DMP) in soil exerts tremendous pressure on soil ecosystems and human health. This study explored the feasibility of using bacterial quorum sensing signal molecules, N -acyl-homoserine lactones (AHLs), to enhance phytoremediation of DMP contaminated soil. The effects of N -butyryl- L -homoserine lactone (C 4 -HSL) on soybean ( Glycine max L.) physiology and phytoremediation efficiency were assessed. Results indicated that C 4 -HSL significantly promoted the efficiency of soybean in remediating DMP contaminated soil, achieving an 87.40 % DMP removal efficiency after 28 d cultivation. Applying C 4 -HSL significantly enhanced soybean photosynthetic by the potential promotion of chlorophyll synthesis and bolstered the antioxidant with a notable reduction in malondialdehyde content. The presence of C 4 -HSL also stimulated plant growth and improved soil enzymatic activities, likely aiding in nutrient cycling and pollutant degradation in soil. Moreover, C 4 -HSL modified the bacterial community, increasing the relative abundance of bacteria related to DMP degradation (Proteobacteria, Actinobacteria) and plant growth promotion (Micromonosporales, Sphingomonadaceae). In general, this study proposed that AHLs-assisted phytoremediation offers a promising, eco-friendly strategy for DMP remediation. This approach provides economic and ecological benefits while reducing damage to soybeans and lays the groundwork for practical applications in agriculture.