000K utf8 1100 $c2022 1500 eng 2050 urn:nbn:de:gbv:8:3-2025-00387-9 2051 10.3390/antiox11122366 3000 Formato, Marialuisa 3010 Calabrò, Serena 3010 Cutrignelli, Monica Isabella 3010 Pacifico, Severina 3010 Piccolella, Simona 3010 Vastolo, Alessandro 3010 Zidorn, Christian 4000 $hMDPI AG [Formato, Marialuisa] 4000 Antioxidants in Animal Nutrition: UHPLC-ESI-QqTOF Analysis and Effects on In Vitro Rumen Fermentation of Oak Leaf Extracts$hMDPI AG [Formato, Marialuisa] 4030 $nMDPI AG 4209 The genus Quercus supplies a large amount of residual material (e.g., bark, acorns, leaves, wood), the valorization of which can favor a supply of antioxidant polyphenols to be used in the pharmaceutical, nutraceutical, or cosmeceutical sector. The recovery of specialized metabolites could also benefit livestock feeding, so much so that polyphenols have gained attention as rumen fermentation modifiers and for mitigating the oxidative imbalance to which farm animals are subject. In this context, leaves of Quercus robur L. from Northern Germany were of interest and the alcoholic extract obtained underwent an untargeted profiling by means of ultra-high-performance liquid chromatography/high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) techniques. As triterpenes and fatty acids occurred, the alcoholic extract fractionation pointed out the obtainment of a polyphenol fraction, broadly constituted by coumaroyl flavonol glycosides and condensed tannins. Total phenol, flavonoid and condensed tannins content assays, as well as antiradical (DPPH● and ABTS+●) and reducing activity (PFRAP) were carried out on the alcoholic extract and its fractions. When the effects on rumen liquor was evaluated in vitro in terms of changes in fermentation characteristics, it was observed that oak leaf extract and its fractions promoted an increase in total volatile fatty acids and differently modulated the relative content of each fatty acid. 4950 https://doi.org/10.3390/antiox11122366$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8:3-2025-00387-9$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00005919 5051 333.7 5051 590 5051 610 5550 Condensed Tannins (Cts) 5550 Flavonoids 5550 In vitro fermentation 5550 Oak Leaves 5550 Quercus Robur L. 5550 Uhplc-esi-qqtof Hr-ms Analysis 5550 Volatile Fatty Acids