Degradation products of aflatoxin M1 (AFM1) formed by high voltage atmospheric cold plasma (HVACP) treatment

Nikmaram, N.; Brückner, L.; Cramer, B.; Humpf, H.-U.; Keener, K.

Abstract

Cold plasma technology is a novel non-thermal technology that has shown promising results for food decontamination and improving food safety. This study is a continuation of a previous investigation of the treatment of AFM1-contaminated skim and whole milk samples by HVACP. Previous research has shown HVACP is effective in degrading aflatoxin M1 (AFM1) in milk. The goal of this study is to identify the degradation products of AFM1 after HVACP treatment in pure water. An HVACP direct treatment at 90 kV using modified air (MA65: 65% O2, 30% CO2, 5% N2) was performed for up to 5 min at room temperature on a 5.0 mL water sample in a Petri dish artificially contaminated with 2 μg/mL of AFM1. The degradants of AFM1 were analyzed and their molecular formulae were elucidated by using high-performance liquid-chromatography time-of-flight mass spectrometry (HPLC−TOF-MS). Three main degradation products were observed and based on mass spectrometric fragmentation pathways, chemical structures for the degradation products were tentatively assigned. According to the structure–bioactivity relationship of AFM1, the bioactivity of the AFM1 samples treated with HVACP was reduced due to the disappearance of the C8–C9 double bond in the furofuran ring in all of the degradation products.