Mechanism of chemical-biological coupling in an electric field-driven bioelectrochemical system for enhanced...

The accumulation of recalcitrant PS presents a significant environmental challenge. However, the low efficiency of natural biodegradation limits the application of existing remediation strategies. Although bioelectrochemical systems (BES) have shown potential in enhancing pollutant removal, the synergistic mechanisms between the electric field and PS biodegradation remain unclear. This study constructed a BES to investigate the degradation of PS by Cupriavidus sp. CP313 using material characterization and integrated multi-omics analyses. Compared to the pure culture system (PS-CP, 12.78% weight loss), the BES-treated group (PS-BES) exhibited significantly enhanced surface erosion, reduced particle size, increased oxygen content, and a higher weight loss of 18.33% over 60 days. GC-MS analysis revealed shorter-chain, more highly oxidized intermediates in the PS-BES group, while long-chain alkanes that persisted in the PS-CP group were undetectable. Multi-omics analyses demonstrated that the electric field upregulated genes, proteins, and pathways related to energy metabolism, aromatic compound degradation, and oxidative stress responses, globally reshaping the metabolic network. The enhancement is attributed primarily to electric field-stimulated microbial metabolic activity rather than direct abiotic oxidation; elevated reactive oxygen species levels were associated with upregulation of key enzymes such as epoxide hydrolases, establishing a microbe-driven oxidative network that promoted the metabolic progression from initial ω‑oxidation toward deeper β‑oxidation pathways, ultimately driving more extensive polymer backbone cleavage. This study provides theoretical foundations and technical references for electric field-assisted biodegradation of plastic waste.