Biodegradation of patulin in apple juice by phosphoribosyl transferase (URA5): implications for food safety

Patulin (PAT), a mycotoxin produced primarily by Penicillium expansum, poses significant health risks and frequently contaminates apples and apple-derived products, often exceeding permissible safety limits. This study investigated the potential of orotate phosphoribosyl transferase (URA5) to degrade PAT in apple juice under controlled conditions. PAT degradation was assessed at initial concentrations of 100 µg/L and 250 µg/L, with enzymatic treatment using 0.2 mg/mL URA5. Samples were incubated for up to 24 h, and PAT degradation was monitored at time intervals of 3, 6, 9, 12, 18, and 24 h using liquid chromatography-mass spectrometry (LC-MS). The results demonstrated a time-dependent PAT degradation, with significant reductions observed as incubation time increased. After 6 h, PAT concentrations decreased to 57.30 µg/L and 112.69 µg/L for the 100 µg/L and 250 µg/L samples, respectively. At 12 h, PAT levels in the 100 µg/L sample fell just below the permissible limit (50 µg/kg), while substantial degradation was observed in the 250 µg/L sample. By 18 h, PAT concentrations dropped further to 47.22 µg/L and 40.10 µg/L, reaching safe consumption levels. After 24 h, degradation rates reached 96.36% and 98.25%, reducing PAT levels to 30.22 µg/L and 31.48 µg/L, confirming the efficacy of URA5 in detoxifying PAT-contaminated apple juice. The findings highlight the potential application of URA5 as a biocatalyst for PAT detoxification in the fruit juice industry. Compared to existing detoxification methods, enzyme-based degradation presents a promising, environmentally friendly, cost-effective, and non-toxic alternative. Further studies should explore its feasibility in large-scale processing and its interaction with other contaminants in commercial apple juice production.