Percorrer por autor "Fernandes, Tiago A."
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- Antioxidant ativities of wine spirits aged by a sustainable technology using chestnut wood staves and micro-oxygenationPublication . Alves, Sheila Oliveira; Lourenço, Sílvia; Anjos, O.; Caldeira, Ilda; Fernandes, Tiago A.; Catarino, Sofia; Canas, SaraAntioxidant ativities of wine spirits aged by a sustainable technology using chestnut wood staves and micro-oxygenation.
- Application of near-infrared spectroscopy to characterize volatile phenols and sensory profile of aged wine spiritsPublication . Anjos, O.; Caldeira, Ilda; Fernandes, Tiago A.; Pedro, Soraia; Vitória, Cláudia; Alves, Sheila Oliveira; Catarino, Sofia; Canas, SaraVolatile phenols are low molecular weight aromatic alcohols, with particular importance in wine spirits aged with wood due to their strong influence on sensory profile.
- Application of Near-Infrared Spectroscopy to characterize volatile phenols and sensory profile of aged wine spiritsPublication . Anjos, O.; Caldeira, Ilda; Fernandes, Tiago A.; Pedro, Soraia; Vitória, Cláudia; Alves, Sheila Oliveira; Catarino, Sofia; Canas, SaraApplication of Near-Infrared Spectroscopy to characterize volatile phenols and sensory profile of aged wine spirits.
- Behaviour of low molecular weight compounds, iron and copper of wine spirit aged with chestnut staves under different levels of micro-oxygenationPublication . Canas, Sara; Danalache, Florina; Anjos, O.; Fernandes, Tiago A.; Caldeira, Ilda; Santos, Nádia; Fargeton, Laurent; Boissier, Benjamin; Catarino, SofiaAlternative technologies for a more sustainable wine spirits' ageing have been studied but a lack of knowledge on the effect of oxygenation level remains. This work examined the behaviour of low molecular weight compounds, iron and copper of a wine spirit aged in 50 L demijohns with chestnut wood staves combined with three levels of micro-oxygenation or nitrogen. Compounds and mineral elements were quantified by HPLC and FAAS, respectively, in samples collected at 8, 21, 60, 180, 270 and 365 days of ageing. Results showed that most of the compounds underwent significant changes in their content over time and behave differently depending on the wine spirit's oxygenation level: higher contents of gallic acid, syringic acid and vanillin were associated with lower micro-oxygenation level while higher contents of ellagic acid, syringaldehyde, coniferaldehyde and sinapaldehyde resulted from higher one; lowest contents of these compounds were found in the nitrogen modality. Weak correlation between copper and the studied compounds was evidenced whereas closer relationship between iron, vanillin, gallic, syringic and ellagic acids at end of ageing was observed. This study provides innovative information on the role of oxygen in wine spirit's ageing, and on chestnut wood effect on wine spirit's mineral composition.
- Casting light on the chemical characterization of acacia podsPublication . Pedro, Soraia; Fernandes, Tiago A.; Antunes, Alexandra M.M.; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.Invasive species impose a strain on natural ecosystems by contributing to the loss of certain native species. Acacia species are amongst the most aggressive invasive species in Portugal. In this work, Acacia retinodes, A. longifolia, A. melanoxylon, A. pycnantha and A. dealbata pods were studied concerning the extraction of compounds for potential industrial application.
- Chemical characterisation of Cytisus striatus: A multi-technique approach using GC-MS, LC-HRMS/MS, NIR, and FT-RAMANPublication . Caramelo, Débora; Fernandes, Tiago A.; Gallardo, Eugenia; Anjos, O.; Gominho, JorgeThe Cytisus striatus species is a biologically important plant recognised for its high flavonoid content. However, the chemical composition of this species has yet to be fully described. The purpose of this study was to identify flavonoids and related secondary metabolites using advanced analytical techniques, including gas chromatography, liquid chromatography, and NIR and Raman spectroscopy. Ethanolic extracts of flowers, fruits, and twigs/leaves contain highly beneficial flavonoids, with chrysin being the main compound detected in all plant parts. It was quantified by HPLC-DAD at levels ranging from 0.90 to 2.27 mg/g extract in samples collected from three different locations. NIR and FT-RAMAN analysis provided complementary information on the overall chemical fingerprint of the plant material. PCA of the spectroscopic data revealed minor site-related differences in global spectral profiles, with PC1 explaining 85% of the variability in flowers and fruits and 72% in twigs/leaves for FT-NIR, while FT-RAMAN analysis of fruit extracts showed a PC1 accounting for 97% of the variance. This study provides a basis for future research on the biological properties of Cytisus striatus and for further assessment of its potential relevance in pharmaceutical and/or food-related applications.
- Comparative analysis of the phytochemical profiles in the flowers and pods of Acacia mearnsiiPublication . Pedro, Soraia; Fernandes, Tiago A.; Antunes, Alexandra M.M.; Gonçalves, José Carlos; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.As espécies do género Acacia são plantas invasoras e extremamente agressivas em vários territórios, representando uma ameaça significativa à biodiversidade e ao equilíbrio dos ecossistemas. Alguns estudos têm sido realizados sobre a composição e atividade biológica em diferentes partes da árvore. Este trabalho tem como objetivo caracterizar extratos de Acacia mearnsii para potencial aplicação industrial.
- First chemical profile analysis of acacia podsPublication . Pedro, Soraia; Fernandes, Tiago A.; Luís, Ângelo; Antunes, Alexandra M.M.; Gonçalves, José Carlos; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.This study intended to evaluate the potential industrial applications of various Acacia species (Acacia melanoxylon, Acacia longifolia, Acacia cyclops, Acacia retinodes, Acacia pycnantha, Acacia mearnsii, and Acacia dealbata) by examining their chemical composition, antioxidant, and antimicrobial properties. Using high-resolution mass spectrometry, a comprehensive analysis successfully identified targeted compounds, including flavonoids (flavonols/flavones) and phenolic acids, such as 4-hydroxybenzoic acid, p-coumaric acid, and ellagic acid. Additionally, p-coumaric acid was specifically identified and quantified within the hydroxycinnamic aldehydes. This comprehensive characterization provides valuable insights into the chemical profiles of the studied species. Among the studied species, A. pycnantha exhibited a higher concentration of total phenolic compounds, including catechin, myricetin, quercetin, and coniferaldehyde. Furthermore, A. pycnantha displayed notable antibacterial activity against K. pneumoniae, E. coli, S. Typhimurium, and B. cereus. The identified compounds in Acacia pods and their shown antibacterial activities exhibit promising potential for future applications. Moreover, vibrational spectroscopy was a reliable method for distinguishing between species. These significant findings enhance our understanding of Acacia species and their potential for various industrial applications.
- Hydrolysable tannins in aged wine spirits: a fresh perspective using alternative ageing technology and high-resolution mass spectrometryPublication . Fernandes, Tiago A.; Antunes, Alexandra M.M.; Alves, Sheila Oliveira; Caldeira, Ilda; Anjos, O.; Catarino, Sofia; Canas, SaraWine spirits (WSs) are usually aged in wooden barrels, but using wood pieces instead of barrels, with or without micro-oxygenation, is a technological alternative that has been investigated by our team.
- Identification of gallotannins and ellagitannins in aged wine spirits : a new perspective using alternative ageing technology and high-resolution mass spectrometryPublication . Fernandes, Tiago A.; Antunes, Alexandra M.M.; Caldeira, Ilda; Anjos, O.; Freitas, Victor; Fargeton, Laurent; Boissier, Benjamin; Catarino, Sofia; Canas, SaraThis research was focused on identifying gallotannins and ellagitannins degradation pathways to better understand their behavior in complex media such as wine spirits (WS). A WS was aged with chestnut wood staves with three levels of micro-oxygenation, nitrogen, and using wooden barrels. Gallotannins and ellagitannins were identified by LC-ESI-HRMS/MS using a Q-TOF in samples collected at 8, 21, 60, 180, 270, and 365 days of ageing, allowed comparing their relative abundances according to the ageing technology. It was established for the first time, the importance of oxygen in gallotannins and ellagitannins formation/degradation pathways in WS and shading light into the explanation for the steady increase of gallic and ellagic acid contents on WS during ageing. The results also highlighted the presence of penta-O-galloyl-β-D-glucose, tetra-O-galloyl-β-D-glucose, tri- O-galloyl-β-D-glucose, di-O-galloyl-β-D-glucose, and mono-O-galloyl-β-D-glucose, 2,3-(S)-hexahydroxydiphenoyl-β-D-glucose, pedunculagin, isomers vescalagin/castalagin and two products stemming from ethanol-promoted oxidation of castalagin/vescalagin and vescalin/castalin, in the composition WS aged with chestnut wood.
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