title: Analysis of the phenolic composition of fungus-resistant grape varieties cultivated in Italy and Germany using UHPLC-MS/MS.
abstract: The phenolic composition of grape berries grown in Italy (Cabernet Cortis, Johanniter, Solaris, Phoenix, and Regent) and in Germany (Regent and Phoenix) was analyzed using two complementary LC-MS/MS (Liquid Chromatography - Tandem Quadrupole Mass Spectrometry) methods. These five cultivars belong to fungus-resistant grape varieties (PIWI) and little is known about their phenolic profile, although phenolics such as phytoalexins have been recognized, playing a key role in the resistance mechanism. A triple quadruple mass spectrometer detector was used for both identification and quantification, and analytical tools from untargeted metabolomics were applied to check and control the quality of the results. Specifically, biological, technical, and instrumental replications were included in order to study the variability at different levels. The results allowed tuning of the sampling protocol and provided a rich phenolic metabolite profile for the aforementioned PIWI varieties, as compared with Vitis vinifera cultivars, especially in the class of stilbenes.
authors.affiliation: Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all´Adige, Italy; Department of Agriculture and Food Science, University of Applied Sciences Neubrandenburg, Brodaer Str. 2, 17033, Neubrandenburg, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Ehrhardt
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Arapitsas
authors.forename: Marco
authors.initials: M
authors.lastname: Stefanini
authors.forename: Gerhard
authors.initials: G
authors.lastname: Flick
authors.forename: Fulvio
authors.initials: F
authors.lastname: Mattivi
keywords: Vitis; fungus-resistant; polyphenols; stilbenoids; targeted metabolomics