Straightforward method to quantify GSH, GSSG, GRP, and hydroxycinnamic acids in wines by UPLC-MRM-MS

Area of Science:

• Analytical Chemistry
• Food Chemistry
• Biochemistry

Background:

• Wine quality is influenced by oxidation and specific compounds.
• Accurate quantification of key molecules like glutathione and hydroxycinnamic acids is crucial for wine analysis.
• Existing methods may lack the speed, robustness, or sensitivity required for comprehensive wine analysis.

Purpose of the Study:

• To develop and validate a novel, rapid, and robust ultrahigh performance liquid chromatography–multiple reaction monitoring mass spectrometry (UHPLC-MRM-MS) method.
• To enable simultaneous quantification of reduced glutathione (GSH), oxidized glutathione (GSSG), grape reaction product (GRP), and hydroxycinnamic acids in various wine types.
• To assess the method's performance characteristics including linearity, precision, accuracy, and matrix effects.

Main Methods:

• Development of a UHPLC-MRM-MS method for simultaneous analysis of GSH, GSSG, GRP, and hydroxycinnamic acids.
• Method validation encompassing linearity, precision, accuracy, limits of detection/quantification, stability, and matrix effects.
• Application of the validated method to analyze white, rosé, and red wine samples with varying oxidation levels.

Main Results:

• The UHPLC-MRM-MS method demonstrated excellent linearity, accuracy (74–110% recovery), and interday precision (RSD <14%) for all target compounds.
• No significant matrix-dependent suppression or enhancement effects were observed, indicating method robustness.
• Analyzed wine samples showed a wide range of concentrations for GSH (1.63–9.91 mg/L), GSSG (0.32–3.33 mg/L), caftaric acid (2.57–293.07 mg/L), and GRP (28.35–114.20 mg/L).

Conclusions:

• The developed UHPLC-MRM-MS method is a reliable and efficient tool for the simultaneous quantification of key compounds in wine.
• The method's applicability was successfully demonstrated across different wine types and oxidation states.
• This analytical approach provides valuable insights into wine composition and oxidative status, supporting quality control and research.