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Updated: Jun 3, 2026

Semi-Targeted Ultra-High-Performance Chromatography Coupled to Mass Spectrometry Analysis of Phenolic Metabolites in Plasma of Elderly Adults
Published on: April 22, 2022
Chemical modifications of polyphenols by plasma-treated water: oxidation, nitration, and adduct formation
Mohammad Bayati1, Brijesh K Tiwari2, Mahesha M Poojary1
1Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark.
None:
Plasma-treated water (PTW) is increasingly explored in food processing, yet its oxidative and nitrosative impacts on the stability of phenolic compounds remain unclear. In this study, individual polyphenols (5 mM) and mixtures of polyphenols with amino acids were treated with PTW. PTW generated after 10 min plasma treatment caused up to 75% degradation of polyphenols, with stability decreasing in the order: p-coumaric acid > phloretic acid > protocatechuic acid > 4-hydroxybenzoic acid > chlorogenic acid. Multiple hydroxylated and nitrated derivatives were identified, including dihydrocaffeic acid and 3-(4-hydroxy-3-nitrophenyl)propanoic acid from phloretic acid, protocatechuic acid and 4-hydroxy-3-nitrobenzoic acid from 4-hydroxybenzoic acid, and 3-nitrocoumaric acid from p-coumaric acid, ranging from 40 μmol to 160 mmol per mol of precursor. Amino acids altered these pathways: cysteine yielded five distinct cysteine-polyphenol adducts, whereas lysine produced two. The results clarify how reactive plasma species modify phenolics and amino acids, underscoring the complexity of oxidation chemistry in PTW-treated systems.
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