Percorrer por autor "Gallardo, Eugenia"
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- Advanced classification of Brazilian stingless bee honey by genus using comprehensive analytical techniques and chemometricsPublication . Ressutte, Jéssica; Galvan, Diego; Luz, Cynthia F.P. da; Gonçalves, Ana Margarida; Rebelo, Kemilla S.; Sattler, José Augusto G.; Passarinha, Luis A.; Gallardo, Eugenia; Anjos, O.; Spinosa, Wilma A.This study aimed to investigate Brazilian stingless bee honey (SBH) to compare their chemical compositions. Fifty-five samples from the genera Melipona, Scaptotrigona, Frieseomelitta, Tetragona, and Tetragonisca, collected from five regions were evaluated by melissopalynological and physicochemical analysis, phenolic compounds, sugar profiling, and FTIR-ATR. Multiblock Analysis (MA) was employed to discriminate and assess the influence of entomological (bee genus) and geographical origins on the honey's characteristics. Subsequently, Linear Discriminant Analysis (LDA) and Partial Least Squares Discriminant Analysis (PLS-DA) were employed to classify the samples based on quantitative data and FTIR-ATR spectra, respectively. The primary factor influencing the chemical profile of Brazilian SBH was entomological origin. MA partially separated samples, while LDA and PLS-DA effectively predicted Melipona, Scaptotrigona, and Tetragonisca samples. Key parameters for separation using MA included sugar profile, phenolic compounds, and FTIR-ATR regions (1800–750 cm⁻¹). In the LDA model, electrical conductivity, pH, color (a*), raffinose content, reducing sugars, and trehalulose + maltose were key for classification. For PLS-DA, spectral regions 1610–1557 cm⁻¹ , 1126–960 cm⁻¹ , and 1170–915 cm⁻¹ were critical for distinguishing samples. This study enhances the understanding of how entomological and geographic factors influence Brazilian SBH characteristics and supports its traceability for quality and authenticity.
- Assessment of mineral and organic compounds from livestock effluentsPublication . Oliveira, Verónica; Vitória, Cláudia; Monteiro, M.C.H.; Anjos, O.; Gallardo, EugeniaO processo eletrodialítico (ED) permite extrair macronutrientes (nitrogénio (N), fósforo (P), cálcio (Ca), potássio (K) e magnésio (Mg)) de efluentes pecuários, para obtenção de fertilizantes minerais de base biológica.
- Caracterização do perfil fenólico em extratos de flores de acácia spp.Publication . Pedro, Soraia; Rosado, Tiago; Barroca, Celina; Neiva, Duarte; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.Caracterização do perfil fenólico em extratos de flores de acácia spp.
- 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.
- Characterisation of the phenolic profile of Acacia retinodes and Acacia mearnsii flowers’ extractsPublication . Pedro, Soraia; Rosado, Tiago; Barroca, Celina; Neiva, Duarte; Alonso-Herranz, Vanesa; Gradillas, Ana; García, Antonia; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.Acacia spp. is an invasive species that is widespread throughout the Portuguese territory. Thus, it is pertinent to better understand this species in order to find different applications that will value its use. To evaluate the phenolic profile in Acacia flowers, ethanolic extracts obtained through an energized guided dispersive extraction were analysed, focusing on two species, Acacia retinodes and Acacia mearnsii, at two flowering stages. The phytochemical profile of each extract was determined by ultra-high performance liquid chromatography coupled with quadrupole time-offlight mass spectrometry and high-performance liquid chromatography coupled with diode array detector. The FTIR-ATR technique was used to distinguish the different samples’ compositions. The results showed the presence of high concentrations of phenolic compounds (>300 mg GAE/g extract), among which are flavonoids (>136 mg QE/g extract), for all combinations of species/flowering stages. The phytochemical profile showed a complex composition with 21 compounds identified and quantified (the predominant ones being epicatechin, rutin, vanillin, and catechol). Both species and flowering stages presented significant variations regarding the presence and quantity of phenols and flavonoids, so much so that a principal component analysis performed with FTIR-ATR spectra data of the extracts was able to discriminate between species and flowering stages.
- Characterization of mineral composition and nutritional value of acacia green podsPublication . Pedro, Soraia; Antunes, Carlos Alberto Lopes; Monteiro, M.C.H. Carmo; Pitacas, F.I.; Gonçalves, Joana; Gominho, Jorge; Gallardo, Eugenia; Anjos, OThe Acacia genus is considered one of the most invasive taxa in some habitats, namely coastal dunes, maritime calcareous soils, fresh lands in the valleys, mountainous areas, and the banks of watercourses and roadsides. In Portugal, the severity risk is very high, so this study aimed to evaluate the nutritional and mineral contents of the green pods as a potential source for livestock feeds and soil fertilizer because, as far as we know, there is no use for this species. The seven different species of Acacia (Acacia mearnsii Link, Acacia longifolia (Andrews) Willd, Acacia melanoxylon R. Br., Acacia pycnantha Bentham, Acacia dealbata Link., Acacia retinodes Schlecht, and Acacia cyclops A. Cunn. ex G. Don fil) were evaluated. The results showed that Acacia green pods have a high protein, fibre and minerals content, especially in potassium (K), calcium (Ca) and magnesium (Mg). All species present a different profile of the studied parameters, suggesting different potentials for their future use. Near-infrared spectroscopy was a potential tool to predict the earlier quality of the Acacia green pods to better select the raw material for the different applications.
- 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.
- Chemical composition and nutritional value of flowers and fruits of Cytisus striatus (Hill) RothmPublication . Caramelo, Débora; Pitacas, F.I.; Vitória, Cláudia; Gonçalves, Joana; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.In ancient times, the shoots of certain species within the Cytisus genus were used as animal feed. Cytisus striatus is a plentiful and widespread shrub that has long been utilized as a soil fertilizer in the Iberian Peninsula. The flowers of this shrub have traditionally been employed for medicinal purposes. However, the nutritional value of yellow broom flowers and fruits remains largely unexplored. In this study, flowers and fruit of C. striatus (Cytisus striatus) were collected from natural shrubs at three different locations in Portugal during the same year. An analytical assessment of their macro and micronutrient content was conducted. Regarding nutritional composition, flowers and fruits exhibited a fibre content of 18% and 42%, protein content of 21% and 12%, lipid content of 2% and 1%, carbohydrate content of 43% and 14%, and ash content of 4% and 3%, respectively. Potassium was the most abundant mineral, with concentrations of approximately 20,094 mg/kg in the flowers and 11,746 mg/kg in the fruits, followed by calcium, phosphorus, and magnesium. Compared to some edible flowers and fruits, these plant parts of C. striatus showed macro and micronutrient values similar to species such as lavender, lupins, and cowpea pod husks.
- 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.
- Comparative phytochemical profiling of flowers and pods in Acacia mearnsiiPublication . Pedro, Soraia; Fernandes, Tiago; Antunes, Alexandra; Gonçalves, J.C.; Gominho,. Jorge; Gallardo, Eugenia; Anjos, O.Comparative phytochemical profiling of flowers and pods in Acacia mearnsii.
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