New insights into immobilized bacterial systems for removal of heavy metals from wastewater

Abstract Industrial and anthropogenic activities release heavy metals (HMs) from natural resources, transforming them into toxic elements. HMs can be extremely toxic, even at very low concentrations; their bioaccumulative nature damages ecosystem endurance and human health. Bacterial bioremediation of HMs is an effective, sustainable, and reliable method owing to inherent and adaptive systems of bacteria that facilitate significant HMs removal via adsorption, ion exchange, and bioaccumulation. However, the use of free cells in wastewater treatment compromises bioremediation efficiency. Bacterial immobilization emerges as a promising visionary technique for treating HMs-contaminated wastewater. Therefore, the present review elucidates the potential of various bacterial remediation mechanisms and highlights current research outcomes in the field of metal ion bioremediation. Furthermore, this review explores the importance and potential applications of bacterial immobilization in the context of metal ion bioremediation. A comprehensive literature review was conducted to demonstrate the advantages of immobilized bacterial cells in HM-contaminated wastewater treatment. The groundbreaking relationship between bacterial HM removal mechanisms and immobilization methods has been conclusively established. Future research that integrates bacterial HM removal mechanisms and bacterial immobilization methods could play an instrumental role in the effective treatment strategies and efficient recovery of HMs from wastewater.