Degradation of patulin in aqueous solution and apple juice by titanium dioxide/graphitic carbon nitride: efficiency, quality and safety

A titanium dioxide/graphitic carbon nitride composite (TiO2/g-C3N4; TOCN) was utilized for the degradation of patulin (PAT). The introduction of carbon nitride into TOCN narrowed the band gap of titanium dioxide (TiO2), thereby enhancing the utilization of the composite with visible light. Patulin at a concentration of 250 μg/kg in aqueous solution and apple juice was degraded respectively by 100% and 85.4% under visible light. The superoxide ion (·O2-) and hydroxyl radical (·OH) play significant roles in the photocatalytic degradation of PAT, and a new degradation product was identified by ultra-high performance liquid chromatography tandem quadrupole orbitrap mass spectrometry (UPLC-Q-Orbitrap MS). In addition, photocatalytic degradation has a minor impact on the quality and nutrition of apple juice. The results of Ames and zebrafish experiments demonstrated that the toxicities of the degradation products were significantly reduced. These results indicate the TOCN photocatalyst can effectively eliminate patulin from aqueous solutions and apple juice, offering a new strategy for removing patulin from food samples.