Impact of indole and its derivatives in the environment: Metabolic mechanisms, functional properties, and ecological...

Indole and its derivatives, as widely prevalent nitrogen-containing heterocyclic compounds, play a complex dual role in environmental systems. Based on a comprehensive review of literature from 2017 to 2025, this work summarizes the metabolic mechanisms, functional properties, and ecological effects of indole and its derivatives, establishing an interdisciplinary framework for understanding their environmental behavior and applications. Significant potential is highlighted in environmental remediation, particularly in enhancing plant-based phytoremediation of heavy metals. These compounds also show promise in the development of novel indole-based materials for efficient adsorption, pollutant degradation, and CO₂ capture. Furthermore, this work critically evaluates their environmental impact, including their effects on aquatic ecosystems and human health, as well as their contribution to the formation of secondary organic aerosols in the atmosphere. Key research challenges are identified, particularly in quantifying environmental transport processes, such as environment-specific degradation rate constants, partition coefficients and half-life, elucidating complex microbial degradation mechanisms, and assessing long-term ecological toxicity. By integrating both beneficial applications and potential risks analysis of indole derivatives, this review aims to foster innovation in environmental science and technological advancement, while also providing a scientific basis for mitigating potential ecological impacts. It concludes a forward-looking perspective on the sustainable environmental use of indole and its derivatives.