A fast and robust UHPLC-MRM-MS method to characterize and quantify grape skin tannins after chemical depolymerization

摘要

A rapid, sensitive, and selective analysis method using ultra high performance liquidchromatography coupled with triple-quadrupole mass spectrometry (UHPLC-QqQ-MS) has beendeveloped for the characterization and quantification of grape skin flavan-3-ols after acid-catalyseddepolymerization in the presence of phloroglucinol (phloroglucinolysis). The compound detectionbeing based on specific MS transitions in Multiple Reaction Monitoring (MRM) mode, this fastgradient robust method allows analysis of constitutive units of grape skin proanthocyanidins,including some present in trace amounts, in a single injection, with a throughput of 6 samplesper hour. This method was applied to a set of 214 grape skin samples from 107 different red andwhite grape cultivars grown under two conditions in the vineyard, irrigated or non-irrigated. Theresults of triplicate analyses confirmed the robustness of the method, which was thus proven to besuitable for high-throughput and large-scale metabolomics studies. Moreover, these preliminaryresults suggest that analysis of tannin composition is relevant to investigate the genetic bases of graperesponse to drought.