γ-Fe2O3 nanoparticle-facilitated bisphenol A degradation by white rot fungus

The effect of γ-Fe2O3 nanoparticles on bisphenol A (BPA) biodegradation by white rot fungus (Pleurotus ostreatus) was investigated. Interestingly, the addition of γ-Fe2O3 nanoparticles enhanced BPA degradation efficiency by as much as 32 % after 3 d in the presence of an environmentally relevant concentration of H2O2. The γ-Fe2O3-induced BPA degradation enhancement was not due to a commonly assumed Fenton-like reaction catalyzed by γ-Fe2O3 or dissolved Fe3+ ions. However, γ-Fe2O3 was bioreduced to Fe3O4, which was more efficient at catalyzing the Fenton reaction, producing a highly active hydroxyl radical. The bioreduction of γ-Fe2O3 was confirmed by X-ray powder diffraction analysis. This study elucidates the potential biotransformation of nanoparticles in the environment and broadens the application of iron oxide nanoparticles for improved pollutant control.