Elimination Mechanism of Methylglyoxal by Naringenin in Foods and Cytotoxicity of Their Adducts

This study aimed to explore the mechanism of action of naringenin in eliminating methylglyoxal (MGO) in foods and to evaluate the cytotoxicity of their reaction products. It was found that the elimination rate of MGO and the inhibition rate of advanced glycation end products (AGEs) by naringenin increased over time under simulated physiological condition (37 ℃ and pH 7.4). After 24 hours, the elimination rate of MGO reached 47.90%, and the inhibition rate of AGEs reached 69.70%. Through high performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) analysis, we elucidated that the elimination mechanism was related to the interaction between MGO and naringenin forming two isomeric adducts, named 8-(1-hydroxyacetone)-naringenin. Next, highly pure adduct standards were prepared and used to develop a method for determining the adducts in foods. In thermally processed foods (biscuits), naringenin could eliminate MGO by forming the adducts and the elimination rate of MGO and the formation levels of the adducts increased with increasing addition of naringenin. At the maximum addition level of 1.0 g/kg, the elimination rate of MGO was 70%, and the content of the adducts was 47.44 mg/kg. The cytotoxicity of the adducts against human gastric, intestinal, and liver cells was close to that of the dietary polyphenol naringenin. In conclusion, naringenin is a safe and effective scavenger for harmful reactive carbonyl compounds, being promising for applications in various fields such as food and pharmaceuticals.