Microbial Synthesis of Nanoparticles for Wastewater Remediation

The wastewater originating from the industrial and domestic sector with potential hazardous organic and inorganic pollutants when discharged into the water bodies causes undesirable effects on the aquatic environment and human health. It is therefore desirable to treat wastewater prior to its disposal. Recently, the application of nanostructured materials for water remediation has gained attention due to their unique size-dependent properties like large surface area, stability, remarkable reusability and recyclability. Nanoparticles represent a promising new technology for wastewater remediation, not only because of their high treatment efficiency but also for their cost-effectiveness, as they have the flexibility for in-situ and ex-situ applications. Several conventional physical and chemical procedures have been reported for the synthesis of metallic and non-metallic nanoparticles. But the environmental hazards associated with the conventional methods restrict the large-scale production and application in water remediation. It is therefore desirable to synthesize nanoparticles using environmentally safer, rapid and inexpensive biogenic approaches based on microbes. Carbohydrates, proteins, polyphenols, vitamins, polymeric substances and several antioxidants obtained from bacteria, fungi and algae have proven their effectiveness as capping and stabilizing agents during greener synthesis of nanomaterials. Application of microbially synthesized nanomaterials for wastewater treatment is a relatively newer but rapidly escalating area of research. The present book chapter outlines the information on recent advances on the microbial synthesis of different types of metallic and non-metallic nanoparticles, their characterization and role in the removal of different types of organic and inorganic pollutants from wastewater.