IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Hemisynthesis, NMR Characterization and UHPLC-Q-Orbitrap /MS² identification of (+)-Catechin oxidation products in red wines and grape seed extracts

Hemisynthesis, NMR Characterization and UHPLC-Q-Orbitrap /MS² identification of (+)-Catechin oxidation products in red wines and grape seed extracts


(+)-Catechin—laccase oxidation dimeric standards were hemi-synthesized using laccase from Trametes versicolor in a water-ethanol solution at pH 3.6. Eight fractions corresponding to eight potential oxidation dimeric products were detected. The fractions profiles were compared with profiles obtained with two other oxidoreductases: polyphenoloxidase extracted from grapes and laccase from Botrytis cinerea. The profiles were very similar, although some minor differences suggested possible dissimilarities in the reactivity of these enzymes. Five fractions were then isolated and analyzed by 1D and 2D NMR spectroscopy. The addition of traces of cadmium nitrate in the samples solubilized in acetone-d6 led to fully resolved NMR signals of phenolic protons, allowing the unambiguous structural determination of six reaction products, one of the fractions containing two enantiomers. These products were then analyzed in grape seed extracts and red wines (UHPLC-Q-Orbitrap MS). The different dimers had different fragmentation patterns according to their interflavan linkage position. Oxidation dimeric compounds had a specific fragment ion at m/z 393, missing for B-Type dimers fragmentations. A fragment ion at m/z 291 occurred and was specific for oxidation dimeric compounds with a C-O-C linkage. Higher level oxidation products had abundant specific fragments: m/z 425, 397 and 245. These fragmentations were useful to identify them in complex samples such as grape seed extracts and wines. Three grape varieties and three ripening stages were selected and the corresponding seed extracts were obtained. The analyses revealed an increasing trend for the oxidation markers during grape ripening. The analysis of Syrah wines (2018, 2014, 2010) showed a decreasing trend of these molecules during wine ageing which might be due to further oxidation.


Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article


Saucier Cedric1, Deshaies Stacy1, Le Guernevé Christine1,2, Sommerer Nicolas1,2, Garcia Lucas Suc François1, Mouls Laetitia1

1SPO, Université de Montpellier, INRAE, Institut Agro, UMR SPO, Faculté de Pharmacie, 15 avenue Charles Flahault, 34000 Montpellier, France
2INRAE, PROBE Research Infrastructure, PFP Polyphenol Facility, 34060 Montpellier, France

Contact the author


wine, grape, polyphenol,oxidation, catechin


IVAS 2022 | IVES Conference Series


Related articles…

Comparison of imputation methods in long and varied phenological series. Application to the Conegliano dataset, including observations from 1964 over 400 grape varieties

A large varietal collection including over 1700 varieties was maintained in Conegliano, ITA, since the 1950s. Phenological data on a subset of 400 grape varieties including wine grapes, table grapes, and raisins were acquired at bud break, flowering, veraison, and ripening since 1964. Despite the efforts in maintaining and acquiring data over such an extensive collection, the data set has varying degrees of missing cases depending on the variety and the year. This is ubiquitous in phenology datasets with significant size and length. In this work, we evaluated four state-of-the-art methods to estimate missing values in this phenological series: k-Nearest Neighbour (kNN), Multivariate Imputation by Chained Equations (mice), MissForest, and Bidirectional Recurrent Imputation for Time Series (BRITS). For each phenological stage, we evaluated the performance of the methods in two ways. 1) On the full dataset, we randomly hold-out 10% of the true values for use as a test set and repeated the process 1000 times (Monte Carlo cross-validation). 2) On a reduced and almost complete subset of varieties, we varied the percentage of missing values from 10% to 70% by random deletion. In all cases, we evaluated the performance on the original values using normalized root mean squared error. For the full dataset we also obtained performance statistics by variety and by year. MissForest provided average errors of 17% (3 days) at budbreak, 14% (4 days) at flowering, 14.5% (7 days) at veraison, and 17% (3 days) at maturity. We completed the imputations of the Conegliano dataset, one of the world’s most extensive and varied phenological time series and a steppingstone for future climate change studies in grapes. The dataset is now ready for further analysis, and a rigorous evaluation of imputation errors is included.

DOSAVIÑA® A new app for a more sustainable use of plant protection products in vineyard

Aims: DOSAVIÑA® was developed with the aim of helping farmers to determine optimal volume rates for spray applications in vineyards. The final developed tool is a good example of bringing research to end users.

Texas terroir: gis characterization of the texas high plains ava

The Texas High Plains AVA is one of eight officially recognized wine regions in Texas, established in 1993. Six local wineries, including the second-largest in Texas, are supported by approximately 50 vineyards, which are also major suppliers of grapes to Texas wineries outside the region.

Benefits and risks of the utilization of grape pomace as organic fertilizers

Rhineland-Palatinate is Germany’s largest wine growing region. The recently launched collaborative project in the frame of the ‘Carl-Zeiss-Stiftungs-Kooperationsfonds für Nachhaltigkeitsforschung’ focusses on the risk-benefit assessment of the use of grape pomace (GP) from the region ‘Pfalz’ in Rhineland-Palatinate as a natural fertilizer

Zoning of viticulture in Yugoslavia

The last official zoning of Viticulture in Yugoslavia was performed 1978. year, when (according to recommendation of OIV and European Economic Community), regions, sub regions and vineyards districts were established supposing that the varieties which will be exhibit ail the positive agro biological and technological characteristics.