Metabolomics and lipidomics focused on polar lipids of kernel and leaves of Corylus avellana cv. Tonda Gentile delle Langhe

Corylus avellana L. (Betulaceae), commonly known as hazelnut tree, is one of the most popular nut trees worldwide. Hazelnuts are a nutritious food, rich in healthy lipids, extensively used by the confectionery industry. They are consumed either raw (with skin) or roasted (without skin) [ 1 ]. Currently, Italy has two hazelnut varieties recognized by the European Union with the Protected Geographical Indication (PGI) label: “Tonda di Giffoni” or “Nocciola di Giffoni” and “Tonda Gentile delle Langhe” or “Nocciola Piemonte” [ 1 ]. After an extensive investigation on the different parts (kernels, shells, leaves, flowers, leafy covers) of C. avellana cv. Giffoni [ 1 ] [ 2 ] [ 3 ] [ 4 ], the objective of the present work was to obtain comprehensive information about the metabolome of the kernels and leaves of C. avellana cv. Piemonte. Polar extracts were subjected to liquid chromatography coupled with electrospray ionization and high-resolution mass spectrometry (LC-ESI/LTQOrbitrap/MS/MS n ). LC-ESI/HRMS profiling of the leaves revealed mono- and diglycosylated flavonoids as well as diarylheptanoid derivatives previously isolated also from C. avellana cv. Giffoni which demonstrated the ability to prevent oxidative damage to human plasma lipids induced by H2O2 and H2O2/Fe 2+ , exhibiting higher antioxidant activity than curcumin [ 1 ] [ 2 ]. LC-ESI/HRMS profiling of the kernels confirmed the presence of phenolic compounds found in the leaves, along with a wide range of polar lipids, from oxylipins and long-chain bases (LCBs and LCBPs) to intact high-molecular-weight phospholipids (l-PC/PC, l-PE/PE, l-PI/PI, l-PA/PA, l-PG/PG, PS, and NA-GPEs), sphingolipids (GlcCers), and glycolipids (DGMG, MAG, SQDG). Based on the biological activities of these polar lipids and their impact on human health, these findings support the inclusion of hazelnuts in human nutrition as a food rich in bioactive and healthy lipids with beneficial effects [ 5 ]. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany