Optimizing difenoconazole degradation via sequential photoelectrochemical oxidation and biodegradation treatments

The growing global demand for food has intensified the use of pesticides in conventional agriculture, raising concerns about their environmental contamination and persistence. This study proposes an integrated strategy for the degradation of difenoconazole (DFZ), combining photoelectrochemical oxidation (PECO) with biodegradation. A mixed metal oxide anode, Ti/(RuO₂)_0.8(Sb₂O₄)_0.1(TiO₂)_0.1 was successfully synthesized via the ionic liquid method, and a mangrove-derived Bacillus sp. isolate was employed in a sequential treatment process. Individually, the Bacillus strain degraded 74.56 % of DFZ1 and 72.52 % of DFZ2, while PECO alone achieved a lower removal efficiency of 32 %. Notably, the sequential application of PECO followed by biodegradation enhanced the degradation rates to 77.81 % for DFZ1 and 74.45 % for DFZ2. Additionally, this combined approach significantly reduced chemical oxygen demand (70.6 %) and toxicity, as evidenced by improved lettuce seed germination indices. These findings underscore the potential of integrating PECO with biodegradation as a promising strategy for the remediation of difenoconazole (DFZ), offering new perspectives for the treatment of recalcitrant triazole compounds in contaminated environments.