Metabolic activity and pathway study of emerging contaminants biodegradation using a photo-bioelectrochemical system: a review.

Abstract

Emerging contaminants and their intermediate residue pose significant risks to human health and ecosystems due to their persistence in water and soil. The review explores the potential of photo-bioelectrochemical systems as a dual-function approach for the degradation of emerging contaminants while simultaneously generating bioenergy. Photo-bioelectrochemical systems integrate microbial metabolism with photocatalytic processes, utilizing solar energy to enhance electron transfer and promote the breakdown of toxic compounds. Recently, this technology has demonstrated improved removal rates of various emerging contaminants, including antibiotics and neonicotinoid pesticides, while producing valuable by-products such as hydrogen and methane through optimized operational conditions. Although studies have focused mainly on pharmaceuticals and dyes, applying these systems for pesticides remains underexplored. Algae-assisted photo-bioelectrochemical systems have been observed frequently in recent studies. This review synthesizes current research on the metabolic activity and biochemical pathways involved in the biodegradation of contaminants within photo-bioelectrochemical systems. It highlights the efficiency of these systems in converting harmful substances into less toxic by-products. It addresses challenges such as slow degradation rates compared to chemical methods and the need for enhanced extracellular electron transfer capabilities among microorganisms. Through optimized operational conditions, this paper aims to provide a comprehensive understanding of photo-bioelectrochemical systems' performance and to propose future research directions for optimizing these systems in real-world applications. In conclusion, this work underscores the promise of photo-bioelectrochemical systems as a sustainable solution for wastewater treatment and environmental remediation.