Degradation of Alternaria mycotoxins by UV-C irradiation: Effect of selected process and exposure to food components

Abstract

Alternariol (AOH) and alternariol monomethyl ether (AME) are two Alternaria mycotoxins with high occurrence rates in food systems. This study aimed to investigate the photodegradation of AOH and AME by ultraviolet-C (UV-C) irradiation. The effect of UV-C intensity, pH, treatment time, solvents and the exposure of food components were evaluated. After treated by UV-C irradiation at 3500 μW/cm² for 90 min, AOH samples in methanol, aqueous solution and solid state were degraded by 89.1%, 72.9% and 53.2%, respectively, while the degradation percentages of AME were 86.6%, 50.1% and 11.1%, respectively. Increasing irradiation intensity and prolonging irradiation time could significantly facilitate the degradation of AOH and AME. An alkaline environment (pH = 11) was more conducive to the degradation of toxins. In addition, 2.5 mg mL⁻¹ citric acid or malic acid increased the photodegradation of AOH and AME to 94.6% and 95.3%, 93.2% and 70.5%, respectively. However, protein, polyphenols and vitamin C exerted inhibitory effects on the degradation, while 10% glucose or sucrose reduced the photodegradation of AOH and AME to 65.9% and 40.3%. UV-C treatment could effectively reduce the content of AOH and AME, with the highest efficiency achieved in methanol and alkaline environment. By contrast, UV-C irradiation is more effective in degrading toxins in some liquid foods rich in organic acids but lacking in protein. The utilization of UV-C radiation appears to be a potentially useful approach for decreasing the underlying risk of Alternaria mycotoxin contamination in foods.

Keywords:

• Alternaria mycotoxins
• AOH
• AME
• UV-C irradiation
• food component

Disclosure statement

No potential conflict of interest was reported by the author(s).

Authors statement

Yike Han, Ziang Zhou and Zihan Cao: Investigation, Methodology, Formal analysis. Wei Zong: Writing, Review and Editing. Guangyuan Zhao: Supervision, Writing, Review and Editing. Xiaoyuan Wang: Investigation, Methodology, Writing, Review and Editing, Funding acquisition, Resources.

Additional information

Funding

This research was supported by Innovation Training Program for College Students of Zhengzhou University of Light Industry.