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Dr. Ana Carvalho
Universidade Católica Portuguesa, CBQF—Centro de Biotecnologia e Química Fina—Laboratório Associado, Escola Superior de Biotecnologia, Porto, Portugal

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0 Lipids
0 bioactive compounds
0 microalgae
0 marine biotechnology

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Journal article
Published: 12 June 2021 in Foods
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The total lipid content and lipidic profile of seaweeds harvested in the North Coast and purchased in Portugal were determined in this paper. The amount of total lipids in the different species of seaweeds varied between 0.7 ± 0.1% (Chondrus crispus) and 3.8 ± 0.6% (Ulva spp.). Regarding the fatty acid content, polyunsaturated fatty acids (PUFA) ranged between 0–35%, with Ulva spp. presenting the highest amount; monounsaturated fatty acids (MUFA) varied between 19 and 67%; and saturated fatty acids (SFA) were predominant in C. crispus (45–78%) and Gracilaria spp. (36–79%). Concerning the nutritional indices, the atherogenicity index (AI) was between 0.4–3.2, the thrombogenicity index (TI) ranged from 0.04 to 1.95, except for Gracilaria spp., which had a TI of 7.6, and the hypocholesterolemic/hypercholesterolemic ratio (HH) values ranged between 0.88–4.21, except for Gracilaria spp., which exhibited values between 0.22–9.26. The n6/n3 ratio was below 1 for most of the species evaluated, except for Ascophyllum nodosum, which presented a higher value, although below 2. Considering the PUFA/SFA ratio, seaweeds presented values between 0.11–1.02. The polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHCs) contamination of seaweeds under study was also quantified, the values found being much lower than the maximum levels recommended for foodstuff.

ACS Style

Cristina Soares; Sara Sousa; Susana Machado; Elsa Vieira; Ana Carvalho; Maria Ramalhosa; Simone Morais; Manuela Correia; Teresa Oliva-Teles; Valentina Domingues; Cristina Delerue-Matos. Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential Contamination. Foods 2021, 10, 1366 .

AMA Style

Cristina Soares, Sara Sousa, Susana Machado, Elsa Vieira, Ana Carvalho, Maria Ramalhosa, Simone Morais, Manuela Correia, Teresa Oliva-Teles, Valentina Domingues, Cristina Delerue-Matos. Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential Contamination. Foods. 2021; 10 (6):1366.

Chicago/Turabian Style

Cristina Soares; Sara Sousa; Susana Machado; Elsa Vieira; Ana Carvalho; Maria Ramalhosa; Simone Morais; Manuela Correia; Teresa Oliva-Teles; Valentina Domingues; Cristina Delerue-Matos. 2021. "Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential Contamination." Foods 10, no. 6: 1366.

Journal article
Published: 08 June 2021 in Materials
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Ferroelectric ceramics (BaTiO3_MnO2) with different Mn admixtures were prepared using solid-state synthesis. Elemental analysis, powder X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and impedance spectroscopy confirmed that the BaTiO3 and MnO2 coexisted in the ceramics. In addition, the high purity and homogeneity of the element distributions in the ceramic samples were confirmed. The adsorptive and photocatalytic properties of the BaTiO3 (reference sample, BTO) and BaTiO3_MnO2 materials (BTO_x, where x is wt.% of MnO2 and x = 1, 2 or 3, denoted as BTO_1, BTO_2 and BTO_3, respectively) were evaluated using Rhodamine B (RhB) as the model dye in a photocatalytic chamber equipped with a UV lamp (15 W) in the absence of additional oxidants and (co)catalysts. No adsorption of RhB dye was found for all the materials during 360 min (dark experiment). All samples were photocatalytically active, and the best results were observed for the BTO_3 material, where RhB was 70% removed from aqueous solution during 360 min of irradiation. The photodegradation of RhB in the presence of MnO2-modified BTO ceramics followed a pseudo-first order model and the rate constant of BTO_3 was about 10 times higher than that of BTO, 2 times that of BTO_2, and 1.5 times that of BTO_1. The photocatalysts could be successfully reused after thermal activation.

ACS Style

Iwona Kuźniarska-Biernacka; Barbara Garbarz-Glos; Elżbieta Skiba; Waldemar Maniukiewicz; Wojciech Bąk; Maija Antonova; Susana Rebelo; Cristina Freire. Evaluation of Rhodamine B Photocatalytic Degradation over BaTiO3-MnO2 Ceramic Materials. Materials 2021, 14, 3152 .

AMA Style

Iwona Kuźniarska-Biernacka, Barbara Garbarz-Glos, Elżbieta Skiba, Waldemar Maniukiewicz, Wojciech Bąk, Maija Antonova, Susana Rebelo, Cristina Freire. Evaluation of Rhodamine B Photocatalytic Degradation over BaTiO3-MnO2 Ceramic Materials. Materials. 2021; 14 (12):3152.

Chicago/Turabian Style

Iwona Kuźniarska-Biernacka; Barbara Garbarz-Glos; Elżbieta Skiba; Waldemar Maniukiewicz; Wojciech Bąk; Maija Antonova; Susana Rebelo; Cristina Freire. 2021. "Evaluation of Rhodamine B Photocatalytic Degradation over BaTiO3-MnO2 Ceramic Materials." Materials 14, no. 12: 3152.

Journal article
Published: 19 May 2021 in Processes
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Mental health and active aging are two of the main concerns in the 21st century. To search for new neuroprotective compounds, extracts of Codium tomentosum Stackhouse and Fucus vesiculosus L. were obtained through multi-step (four step) subcritical water extraction using a temperature gradient. The safety assessment of the extracts was performed by screening pharmaceutical compounds and pesticides by UHPLC-MS/MS, and iodine and arsenic levels by ICP-MS. Although the extracts were free of pharmaceutical compounds and pesticides, the presence of arsenic and high iodine contents were found in the first two extraction steps. Thus, the health-benefits were only evaluated for the fractions obtained in steps 3 and 4 from the extraction process. These fractions were tested against five brain enzymes implicated in Alzheimer’s, Parkinson’s, and major depression etiology as well as against reactive oxygen and nitrogen species, having been observed a strong enzyme inhibition and radical scavenging activities for the step 4 fractions from both seaweed species. Regarding the variation of the chemical composition during the extraction, step 1 fractions were the richest in phenolic compounds. With the increase in temperature, Maillard reaction, caramelization and thermo-oxidation occurred, and the resulting products positively affected the antioxidant capacity and the neuroprotective effects.

ACS Style

Cristina Soares; Paula Paíga; Marta Marques; Tânia Neto; Ana Carvalho; Alexandre Paiva; Pedro Simões; Leonor Costa; Ana Bernardo; Naiara Fernández; Edgar Pinto; Agostinho Almeida; Maria Bronze; Cristina Delerue-Matos; Clara Grosso. Multi-Step Subcritical Water Extracts of Fucus vesiculosus L. and Codium tomentosum Stackhouse: Composition, Health-Benefits and Safety. Processes 2021, 9, 893 .

AMA Style

Cristina Soares, Paula Paíga, Marta Marques, Tânia Neto, Ana Carvalho, Alexandre Paiva, Pedro Simões, Leonor Costa, Ana Bernardo, Naiara Fernández, Edgar Pinto, Agostinho Almeida, Maria Bronze, Cristina Delerue-Matos, Clara Grosso. Multi-Step Subcritical Water Extracts of Fucus vesiculosus L. and Codium tomentosum Stackhouse: Composition, Health-Benefits and Safety. Processes. 2021; 9 (5):893.

Chicago/Turabian Style

Cristina Soares; Paula Paíga; Marta Marques; Tânia Neto; Ana Carvalho; Alexandre Paiva; Pedro Simões; Leonor Costa; Ana Bernardo; Naiara Fernández; Edgar Pinto; Agostinho Almeida; Maria Bronze; Cristina Delerue-Matos; Clara Grosso. 2021. "Multi-Step Subcritical Water Extracts of Fucus vesiculosus L. and Codium tomentosum Stackhouse: Composition, Health-Benefits and Safety." Processes 9, no. 5: 893.

Journal article
Published: 09 April 2021 in Colloids and Surfaces A: Physicochemical and Engineering Aspects
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A straightforward and environmentally-friendly approach for the fabrication of TiO2 supported nano-Au and Ag catalysts with enhanced activity in nitroarenes reduction is presented. The immobilization of the metal nanoparticles (NPs) onto TiO2 was performed through a first step of metal precursors adsorption (tetrachloroauric(III) acid trihydrate or silver(I) nitrate) onto TiO2, followed by a step of in situ metal cations reduction using three types of reducing agents: citric acid, NaBH4 and simulated sunlight irradiation. The type of reducing agent influenced the size, the oxidation state and loading of the grafted metal NPs. The Au-based nanocomposites contained Au NPs with sizes ranging between 19.3 and 28.2 nm and Au loadings in the range of 7.2−19.8 wt%. NaBH4 was the best reducing agent for the Au NPs immobilization onto TiO2, leading to the highest Au loading (19.8 wt%) and lowest Au+/Au0 ratio (0.07). In the case of the Ag-based materials, citric acid revealed to be the best reducing agent for the Ag NPs immobilization onto TiO2, leading to ultrasmall grafted NPs, 10.1 wt% Ag loading and the highest amount of metallic silver (Ag+/Ag0 ratio = 0.03). The catalytic performance of the Au/Ag-based TiO2 nanocomposites was evaluated in the reduction of 4-nitrophenol (4-NP) and 4-nitroaniline (4-NA) in aqueous medium, at room temperature, using NaBH4 as reducing agent (substrate:reducing agent:catalyst weight ratio = 0.007:1.89:1). The Au- and Ag-based nanocomposites (prepared with NaBH4 and citric acid, respectively) led to 100% conversion of 4-NP within 260 and 40 s, respectively, with rate constants (k) of 19.1×10-3 and 94.2×10-3 s-1 (pseudo-first-order kinetics), respectively, demonstrating the higher performance of the Ag-based catalyst. In contrast, in the case of the 4-NA reduction, the highest catalytic performance was achieved for the Au-based material, promoting the total substrate conversion within 90 s (k = 29.4×10-3 s-1), while for the Ag-based catalyst the total 4-NA conversion was achieved within 120 s (k = 16.6×10-3 and 27.5×10-3 s-1). Both catalysts were reused in nine consecutive cycles in both 4-NP and 4-NA reduction, with the Au-based material presenting higher stability, especially for 4-NA reduction, with only a small reaction time increment.

ACS Style

Mariana Rocha; Clara Pereira; Cristina Freire. Au/Ag nanoparticles-decorated TiO2 with enhanced catalytic activity for nitroarenes reduction. Colloids and Surfaces A: Physicochemical and Engineering Aspects 2021, 621, 126614 .

AMA Style

Mariana Rocha, Clara Pereira, Cristina Freire. Au/Ag nanoparticles-decorated TiO2 with enhanced catalytic activity for nitroarenes reduction. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2021; 621 ():126614.

Chicago/Turabian Style

Mariana Rocha; Clara Pereira; Cristina Freire. 2021. "Au/Ag nanoparticles-decorated TiO2 with enhanced catalytic activity for nitroarenes reduction." Colloids and Surfaces A: Physicochemical and Engineering Aspects 621, no. : 126614.

Journal article
Published: 13 February 2021 in Materials
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Fuel cells are emerging devices as clean and renewable energy sources, provided their efficiency is increased. In this work, we prepared nanocomposites based on multiwalled carbon nanotubes (MWNTs) and transition metal dichalcogenides (TMDs), namely WS2 and MoS2, and evaluated their performance as electrocatalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), relevant to fuel cells. The one- and two-dimensional (1D and 2D) building blocks were initially exfoliated and non-covalently functionalized by surfactants of opposite charge in aqueous media (tetradecyltrimethylammonium bromide, TTAB, for the nanotubes and sodium cholate, SC, for the dichalcogenides), and thereafter, the three-dimensional (3D) [email protected] and [email protected] composites were assembled via surfactant-mediated electrostatic interactions. The nanocomposites were characterized by scanning electron microscopy (SEM) and structural differences were found. [email protected] and [email protected] show moderate ORR performance with potential onsets of 0.71 and 0.73 V vs. RHE respectively, and diffusion-limiting current densities of −1.87 and −2.74 mA·cm−2, respectively. Both materials present, however, better tolerance to methanol crossover when compared to Pt/C and good stability. Regarding OER performance, [email protected] exhibits promising results, with η 10 and j max of 0.55 V and 17.96 mA·cm−2, respectively. The fabrication method presented here is cost-effective, robust and versatile, opening the doors for the optimization of electrocatalysts’ performance.

ACS Style

Pedro Ferreira; Bárbara Abreu; Cristina Freire; Diana Fernandes; Eduardo Marques. Nanocomposites Prepared from Carbon Nanotubes and the Transition Metal Dichalcogenides WS2 and MoS2 via Surfactant-Assisted Dispersions as Electrocatalysts for Oxygen Reactions. Materials 2021, 14, 896 .

AMA Style

Pedro Ferreira, Bárbara Abreu, Cristina Freire, Diana Fernandes, Eduardo Marques. Nanocomposites Prepared from Carbon Nanotubes and the Transition Metal Dichalcogenides WS2 and MoS2 via Surfactant-Assisted Dispersions as Electrocatalysts for Oxygen Reactions. Materials. 2021; 14 (4):896.

Chicago/Turabian Style

Pedro Ferreira; Bárbara Abreu; Cristina Freire; Diana Fernandes; Eduardo Marques. 2021. "Nanocomposites Prepared from Carbon Nanotubes and the Transition Metal Dichalcogenides WS2 and MoS2 via Surfactant-Assisted Dispersions as Electrocatalysts for Oxygen Reactions." Materials 14, no. 4: 896.

Journal article
Published: 19 December 2020 in Biomass and Bioenergy
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Post-grafting methodologies were used to prepare aryl-organosulfonic acid functionalized silica nanoparticles (SO3H-aryl-SiO2NPs) as highly active heterogeneous acid catalysts for catalytic esterification of free fatty acids (FFA) and levulinic acid (LA), and aldol condensation of furfural with 3-methylfuran, well known renewable feedstocks for biodiesel and fuel additives production. The chemical and structural characterization of the SO3H-aryl-SiO2NPs confirmed the success of the functionalization. Complete conversion for all FFA was observed using SO3H-aryl-SiO2NPs after 2 h of reaction. SiO2NPs_CSPTMS showed to be the most active and stable catalyst with no significant loss of activity in the first 5 cycles. In the LA esterification in the presence of an alcohol, complete conversion and selectivity and high reusability were observed (e.g., 83.2% yield after 10 cycles in the presence of 1-propanol, SiO2NPs10_CSPTMS, at 120 °C and 2h reaction). Finally, aldol condensation of furfural and 3-methylfuran had been performed using SiO2NPs_CSPTMS catalysts with almost 100% yield after 10 min at 65 °C, high stability and reusability for 7 catalytic cycles. In general, the prepared SO3H-aryl-SiO2NPs have demonstrated promising catalytic performance for transformation of biomass-derived feedstocks into biodiesel and fuel additives.

ACS Style

Andreia F. Peixoto; Mohamed M.A. Soliman; Tânia V. Pinto; Sónia M. Silva; Paula Costa; Elisabete C.B.A. Alegria; Cristina Freire. Highly active organosulfonic aryl-silica nanoparticles as efficient catalysts for biomass derived biodiesel and fuel additives. Biomass and Bioenergy 2020, 145, 105936 .

AMA Style

Andreia F. Peixoto, Mohamed M.A. Soliman, Tânia V. Pinto, Sónia M. Silva, Paula Costa, Elisabete C.B.A. Alegria, Cristina Freire. Highly active organosulfonic aryl-silica nanoparticles as efficient catalysts for biomass derived biodiesel and fuel additives. Biomass and Bioenergy. 2020; 145 ():105936.

Chicago/Turabian Style

Andreia F. Peixoto; Mohamed M.A. Soliman; Tânia V. Pinto; Sónia M. Silva; Paula Costa; Elisabete C.B.A. Alegria; Cristina Freire. 2020. "Highly active organosulfonic aryl-silica nanoparticles as efficient catalysts for biomass derived biodiesel and fuel additives." Biomass and Bioenergy 145, no. : 105936.

Review
Published: 30 October 2020 in Journal of CO2 Utilization
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The recycling of carbon dioxide via its electroreduction (CO2RR) is a key factor to stimulate the capture of this greenhouse gas, being a promising green strategy for achieving sustainable development. Nanostructured carbon materials play a protagonist role in the search of efficient and selective CO2RR electrocatalysts and, at the same time, pyrolysis is one of the most versatile tools to produce tailored nanocarbons. Nanocarbons involving a variety of dopants, metal single-atom sites/nanoparticles and textural/structural arrangements can be obtained through rational precursor/s selection and control of the carbonization conditions. Thus, this review aims to highlight the advances in CO2RR electrocatalysis using nanocarbons derived from MOFs, biomass, polymers, and other precursors, assessing the aspects to improve as well. Bearing in mind that selectivity toward valuable products is the ever-present obstacle, we summarize the nature and proportion of the produced compounds. With this, we provide a useful guide in which carbon synthetic conditions, structural features and electrocatalytic metrics are correlated to facilitate further progress in this boisterous field. After all, the main limitations detected in CO2RR research as well as potential approaches to address them are included.

ACS Style

Víctor K. Abdelkader-Fernández; Diana M. Fernandes; Cristina Freire. Carbon-based electrocatalysts for CO2 electroreduction produced via MOF, biomass, and other precursors carbonization: A review. Journal of CO2 Utilization 2020, 42, 101350 .

AMA Style

Víctor K. Abdelkader-Fernández, Diana M. Fernandes, Cristina Freire. Carbon-based electrocatalysts for CO2 electroreduction produced via MOF, biomass, and other precursors carbonization: A review. Journal of CO2 Utilization. 2020; 42 ():101350.

Chicago/Turabian Style

Víctor K. Abdelkader-Fernández; Diana M. Fernandes; Cristina Freire. 2020. "Carbon-based electrocatalysts for CO2 electroreduction produced via MOF, biomass, and other precursors carbonization: A review." Journal of CO2 Utilization 42, no. : 101350.

Books
Published: 28 October 2020 in Catalysis Series
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Oxidovanadium complexes are an important class of homogeneous catalysts with paramount importance for the synthesis of valuable fine and bulk chemicals and chemical intermediates. However, their low chemical–thermal stability and difficult separation from the reaction medium hamper their implementation in industrial processes. In this sense, the quest for recyclable and eco-sustainable supported vanadium-based catalytic systems has been a longstanding goal. The aim of this chapter is to provide an overview of the widespread potential of supported vanadium complexes and other vanadium-containing solid-state compounds as eco-sustainable recyclable catalysts on several important reactions for the production of high value-added products. The progress on the development of efficient and reusable oxidovanadium catalysts immobilized onto different types of bulk and nano supports, or integrated on organic framework structures, will be reviewed. Special emphasis will be given to literature reports in which the catalytic performance of the vanadium-based heterogeneous systems surpasses that of the corresponding homogeneous counterparts. The application of vanadium-based materials as electrocatalysts for reduction–oxidation reactions relevant for renewable energy storage and conversion technologies will be also described. Subsequently, vanadium-mediated catalytic reactions for biomass valorization will be addressed. Finally, some insights on the latest theoretical findings on supported vanadium catalysts will be provided.

ACS Style

Cristina Freire; Clara Pereira; Bruno Jarrais; Diana Fernandes; Andreia Peixoto; Natália Cordeiro; Filipe Teixeira. Chapter 11. Supported Vanadium Catalysts: Heterogeneous Molecular Complexes, Electrocatalysis and Biomass Transformation. Catalysis Series 2020, 241 -284.

AMA Style

Cristina Freire, Clara Pereira, Bruno Jarrais, Diana Fernandes, Andreia Peixoto, Natália Cordeiro, Filipe Teixeira. Chapter 11. Supported Vanadium Catalysts: Heterogeneous Molecular Complexes, Electrocatalysis and Biomass Transformation. Catalysis Series. 2020; ():241-284.

Chicago/Turabian Style

Cristina Freire; Clara Pereira; Bruno Jarrais; Diana Fernandes; Andreia Peixoto; Natália Cordeiro; Filipe Teixeira. 2020. "Chapter 11. Supported Vanadium Catalysts: Heterogeneous Molecular Complexes, Electrocatalysis and Biomass Transformation." Catalysis Series , no. : 241-284.

Journal article
Published: 10 July 2020 in Food Chemistry
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The objective of this study was to evaluate the optimal Subcritical Water Extraction (SWE) conditions of antioxidants and polyphenols from chestnut shells using Response Surface Methodology (RSM). A central composite design (CCD) was conducted to analyse the time (6–30 min) and temperature (51–249 °C) effects in antioxidant activity (ABTS, DPPH and FRAP) and Total Phenolic Compounds (TPC). TPC ranged from 315.21 to 496.80 mg gallic acid equivalents (GAE)/g DW; the DPPH from 549.23 to 1125.68 mg Trolox equivalents (TE)/g DW; ABTS varied between 631.16 and 965.45 mg ascorbic acid equivalents (AAE)/g DW and FRAP from 2793.95 to 11393.97 mg ferrous sulphate equivalents (FSE)/g DW. The optimal extraction conditions were 30 min/220 °C, revealing excelling scavenging efficiencies against HOCl (IC50 = 0.79 µg/mL) and O2− (IC50 = 12.92 µg/mL) without toxicity on intestinal cells (0.1 µg/mL). The phenolic composition revealed high amounts of pyrogallol and protocatechuic acid. SWE can be a useful extraction technique for the recovery of polyphenolics from chestnut shells.

ACS Style

Diana Pinto; Elsa F. Vieira; Andreia F. Peixoto; Cristina Freire; Vitor Freitas; Paulo Costa; Cristina Delerue-Matos; Francisca Rodrigues. Optimizing the extraction of phenolic antioxidants from chestnut shells by subcritical water extraction using response surface methodology. Food Chemistry 2020, 334, 127521 .

AMA Style

Diana Pinto, Elsa F. Vieira, Andreia F. Peixoto, Cristina Freire, Vitor Freitas, Paulo Costa, Cristina Delerue-Matos, Francisca Rodrigues. Optimizing the extraction of phenolic antioxidants from chestnut shells by subcritical water extraction using response surface methodology. Food Chemistry. 2020; 334 ():127521.

Chicago/Turabian Style

Diana Pinto; Elsa F. Vieira; Andreia F. Peixoto; Cristina Freire; Vitor Freitas; Paulo Costa; Cristina Delerue-Matos; Francisca Rodrigues. 2020. "Optimizing the extraction of phenolic antioxidants from chestnut shells by subcritical water extraction using response surface methodology." Food Chemistry 334, no. : 127521.

Journal article
Published: 07 July 2020 in Science of The Total Environment
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This paper assesses the applicability of a new carob waste-derived powdered activated carbon (PAC) obtained by steam activation for pharmaceutical compounds (PhCs) removal in urban wastewater treatment plants (WWTPs) with activated sludge (AS) secondary treatment. The new carob-derived PAC presents chemical and textural properties similar to a high-performing commercial PAC produced from vegetable source by physical activation. The adsorption isotherms of three target PhCs, carbamazepine, diclofenac and sulfamethoxazole, spiked (at around 100 μg/L) in mixed liquor (ML) and in clarified-ML from the AS-bioreactor of a WWTP show: (i) minor reduction of PAC capacity with real MLs compared to clarified MLs; (ii) the higher the PhC hydrophobicity, the higher the PAC adsorption capacity in both water matrices; (iii) hydrophobic interactions probably overweight electrostatic interactions between the PhCs and the slightly positively charged PAC in these real water matrices with background organics and inorganics. The PhC adsorption results with ML and clarified-ML are used to calibrate the IAST-based tracer model (TRM) and predict the new PAC performance when added to AS-bioreactor vs. in post-secondary treatment, at the PhC naturally-occurring trace concentrations. The modelling projections show (i) one needs higher PAC doses than those reported in the literature, particularly in post-treatment, and (ii) the benefits of PAC dosing to the bioreactor, with only a slightly higher PAC dose being needed when compared to its post-secondary dosing and minimising the capital investment.

ACS Style

Rui M.C. Viegas; Ana S. Mestre; Elsa Mesquita; Margarida Campinas; Marta A. Andrade; Ana P. Carvalho; Maria João Rosa. Assessing the applicability of a new carob waste-derived powdered activated carbon to control pharmaceutical compounds in wastewater treatment. Science of The Total Environment 2020, 743, 140791 .

AMA Style

Rui M.C. Viegas, Ana S. Mestre, Elsa Mesquita, Margarida Campinas, Marta A. Andrade, Ana P. Carvalho, Maria João Rosa. Assessing the applicability of a new carob waste-derived powdered activated carbon to control pharmaceutical compounds in wastewater treatment. Science of The Total Environment. 2020; 743 ():140791.

Chicago/Turabian Style

Rui M.C. Viegas; Ana S. Mestre; Elsa Mesquita; Margarida Campinas; Marta A. Andrade; Ana P. Carvalho; Maria João Rosa. 2020. "Assessing the applicability of a new carob waste-derived powdered activated carbon to control pharmaceutical compounds in wastewater treatment." Science of The Total Environment 743, no. : 140791.

Journal article
Published: 03 July 2020 in Foods
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This work focused on evaluating the possibility of using vineyard pruning wastes from two Portuguese Vitis vinifera varieties; Touriga Nacional (TN) and Tinta Roriz (TR), as new potential ingredients for the nutraceutical industry. An environmentally friendly extraction technique; namely subcritical-water extraction (SWE), was employed. The overall results indicate that phenolic acids were the major class of compounds quantified; being gallic acid the principal one. The highest value for total phenolic content (TPC) was obtained for the TR extract at 250 °C (181 ± 12 mg GAE/g dw). In terms of antioxidant activity; the DPPH values for the extracts obtained at 250 °C were approximately 4-fold higher than the ones obtained at 125 °C; with TR extract presenting the highest value (203 ± 22 mg TE/g dw). Thus, the TR extract obtained through SWE at 250 °C was selected to evaluate the scavenging activity and the in vitro effects on cells due to the best results achieved in the previous assays. This extract presented the ability to scavenge reactive oxygen species (O2●-, HOCl and ROO●). No adverse effects were observed in HFF-1 viability after exposure to extract concentrations below 100 μg/mL. This work demonstrated that vine-canes extracts could be a potential ingredient to nutraceutical industry

ACS Style

Olena Dorosh; Manuela M. Moreira; Diana Pinto; Andreia F. Peixoto; Cristina Freire; Paulo Costa; Francisca Rodrigues; Cristina Delerue-Matos. Evaluation of the Extraction Temperature Influence on Polyphenolic Profiles of Vine-Canes (Vitis vinifera) Subcritical Water Extracts. Foods 2020, 9, 872 .

AMA Style

Olena Dorosh, Manuela M. Moreira, Diana Pinto, Andreia F. Peixoto, Cristina Freire, Paulo Costa, Francisca Rodrigues, Cristina Delerue-Matos. Evaluation of the Extraction Temperature Influence on Polyphenolic Profiles of Vine-Canes (Vitis vinifera) Subcritical Water Extracts. Foods. 2020; 9 (7):872.

Chicago/Turabian Style

Olena Dorosh; Manuela M. Moreira; Diana Pinto; Andreia F. Peixoto; Cristina Freire; Paulo Costa; Francisca Rodrigues; Cristina Delerue-Matos. 2020. "Evaluation of the Extraction Temperature Influence on Polyphenolic Profiles of Vine-Canes (Vitis vinifera) Subcritical Water Extracts." Foods 9, no. 7: 872.

Paper
Published: 29 June 2020 in Dalton Transactions
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We report the application of Ru/CNT for the catalytic reduction of nitroarenes and the electrocatalytic oxygen reactions (ORR/OER).

ACS Style

Diana M. Fernandes; Mariana Rocha; Camila Rivera-Cárcamo; Philippe Serp; Cristina Freire. Ru single atoms and nanoparticles on carbon nanotubes as multifunctional catalysts. Dalton Transactions 2020, 49, 10250 -10260.

AMA Style

Diana M. Fernandes, Mariana Rocha, Camila Rivera-Cárcamo, Philippe Serp, Cristina Freire. Ru single atoms and nanoparticles on carbon nanotubes as multifunctional catalysts. Dalton Transactions. 2020; 49 (29):10250-10260.

Chicago/Turabian Style

Diana M. Fernandes; Mariana Rocha; Camila Rivera-Cárcamo; Philippe Serp; Cristina Freire. 2020. "Ru single atoms and nanoparticles on carbon nanotubes as multifunctional catalysts." Dalton Transactions 49, no. 29: 10250-10260.

Paper
Published: 18 June 2020 in Journal of Materials Chemistry A
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Increasing the POM loadings in [email protected] nanocomposites prepared in situ results in extremely modified framework electrocatalysts with highly enhanced OER performances.

ACS Style

Víctor K. Abdelkader-Fernández; Diana M. Fernandes; Salete S. Balula; Luís Cunha-Silva; Cristina Freire. Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts. Journal of Materials Chemistry A 2020, 8, 13509 -13521.

AMA Style

Víctor K. Abdelkader-Fernández, Diana M. Fernandes, Salete S. Balula, Luís Cunha-Silva, Cristina Freire. Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts. Journal of Materials Chemistry A. 2020; 8 (27):13509-13521.

Chicago/Turabian Style

Víctor K. Abdelkader-Fernández; Diana M. Fernandes; Salete S. Balula; Luís Cunha-Silva; Cristina Freire. 2020. "Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts." Journal of Materials Chemistry A 8, no. 27: 13509-13521.

Journal article
Published: 10 April 2020 in Molecules
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Wine production generates large amounts of vine-canes, a devalued by-product that could be used for the recovery of bioactive compounds. In this work, two vine-canes varieties, namely Touriga Nacional (TN) and Tinta Roriz (TR), were submitted to different ultrasound-assisted extraction (UAE) conditions. The highest phenolic and flavonoid content was observed for TR extract obtained at lab-scale without an ice bath and pilot-scale after 60 min of extraction (32.6 ± 2.1 and 26.0 ± 1.5 mg gallic acid equivalent/g dry weight (dw) and 9.5 ± 0.6 and 8.3 ± 0.8 mg epicatechin equivalents/g dw, respectively). Further, all extracts demonstrated a high antioxidant activity to scavenge DPPH free radicals with the best value reached by TR at the lab-scale without an ice bath after 30 min and pilot-scale extraction after 60 min (34.2 ± 2.4 and 33.4 ± 2.1 mg trolox equivalents/g dw, respectively). Extracts phenolic composition were also evaluated by HPLC, demonstrating that resveratrol, myricetin and catechin were the main compounds. According to our knowledge, this is the first time that a pilot scale of UAE of phenolic compounds from vine-canes was performed. This paper represents an important step to the use of UAE as an industrial process to recover bioactive compounds.

ACS Style

Olena Dorosh; Manuela M. Moreira; Francisca Rodrigues; Andreia F. Peixoto; Cristina Freire; Simone Morais; Cristina Delerue-Matos. Vine-Canes Valorisation: Ultrasound-Assisted Extraction from Lab to Pilot Scale. Molecules 2020, 25, 1739 .

AMA Style

Olena Dorosh, Manuela M. Moreira, Francisca Rodrigues, Andreia F. Peixoto, Cristina Freire, Simone Morais, Cristina Delerue-Matos. Vine-Canes Valorisation: Ultrasound-Assisted Extraction from Lab to Pilot Scale. Molecules. 2020; 25 (7):1739.

Chicago/Turabian Style

Olena Dorosh; Manuela M. Moreira; Francisca Rodrigues; Andreia F. Peixoto; Cristina Freire; Simone Morais; Cristina Delerue-Matos. 2020. "Vine-Canes Valorisation: Ultrasound-Assisted Extraction from Lab to Pilot Scale." Molecules 25, no. 7: 1739.

Journal article
Published: 28 March 2020 in Talanta
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This work reports the development of an electrochemical immunosensor for rapid, specific and decentralized detection of the invasion-associated protein p60 secreted by Listeria monocytogenes, a life-threatening foodborne pathogen. A disposable screen-printed electrode was used as transducer surface and monoclonal and polyclonal antibodies that specifically recognize Listeria monocytogenes p60 protein and Listeria spp. p60 proteins, respectively, were used as the sandwich immuno-pair. The reaction was detected with the aid of an additional secondary antibody conjugated with the enzyme reporter (alkaline phosphatase) and using 3-indoxyl phosphate/silver ions as the mixture substrate. The analytical signal was acquired through the voltammetric stripping of the enzymatically deposited silver, which was directly correlated to p60 concentration in the sample. In optimized conditions, a limit of detection and quantification of 1.5 ng mL−1 and 5.1 ng mL−1 were achieved, respectively, in a useful time (<3 h). As proof-of-concept, the proposed immunosensor was successfully applied to spiked milk samples, demonstrating to be a suitable device for further use in real sample detection of Listeria monocytogenes in food products.

ACS Style

Nádia Silva; Marta M.P.S. Neves; Júlia Maria Magalhaes; Cristina Freire; Cristina Delerue-Matos. Electrochemical immunosensor towards invasion-associated protein p60: An alternative strategy for Listeria monocytogenes screening in food. Talanta 2020, 216, 120976 .

AMA Style

Nádia Silva, Marta M.P.S. Neves, Júlia Maria Magalhaes, Cristina Freire, Cristina Delerue-Matos. Electrochemical immunosensor towards invasion-associated protein p60: An alternative strategy for Listeria monocytogenes screening in food. Talanta. 2020; 216 ():120976.

Chicago/Turabian Style

Nádia Silva; Marta M.P.S. Neves; Júlia Maria Magalhaes; Cristina Freire; Cristina Delerue-Matos. 2020. "Electrochemical immunosensor towards invasion-associated protein p60: An alternative strategy for Listeria monocytogenes screening in food." Talanta 216, no. : 120976.

Journal article
Published: 28 March 2020 in Materials
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To address aggravating environmental and energy problems, active, efficient, low-cost, and robust electrocatalysts (ECs) are actively pursued as substitutes for the current noble metal ECs. Therefore, in this study, we report the preparation of graphene flakes (GF) doped with S and N using 2-5-dimercapto-1,3,4-thiadiazole (S3N2) as precursor followed by the immobilization of cobalt spinel oxide (Co3O4) or manganese spinel oxide (Mn3O4) nanoparticles through a one-step co-precipitation procedure (Co/S3N2–GF and Mn/S3N2–GF). Characterization by different physicochemical techniques (Fourier Transform Infrared (FTIR), Raman spectroscopy, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD)) of both composites shows the preservation of the metal oxide spinel structure and further confirms the successful preparation of the envisaged electrocatalysts. Co/S3N2–GF composite exhibits the best ORR performance with an onset potential of 0.91 V vs. RHE, a diffusion-limiting current density of −4.50 mA cm−2 and selectivity for the direct four-electron pathway, matching the results obtained for commercial Pt/C. Moreover, both Co/S3N2–GF and Mn/S3N2–GF showed excellent tolerance to methanol poisoning and good stability.

ACS Style

Penny Mathumba; Diana M. Fernandes; Renata Matos; Emmanuel I. Iwuoha; Cristina Freire. Metal Oxide (Co3O4 and Mn3O4) Impregnation into S, N-doped Graphene for Oxygen Reduction Reaction (ORR). Materials 2020, 13, 1562 .

AMA Style

Penny Mathumba, Diana M. Fernandes, Renata Matos, Emmanuel I. Iwuoha, Cristina Freire. Metal Oxide (Co3O4 and Mn3O4) Impregnation into S, N-doped Graphene for Oxygen Reduction Reaction (ORR). Materials. 2020; 13 (7):1562.

Chicago/Turabian Style

Penny Mathumba; Diana M. Fernandes; Renata Matos; Emmanuel I. Iwuoha; Cristina Freire. 2020. "Metal Oxide (Co3O4 and Mn3O4) Impregnation into S, N-doped Graphene for Oxygen Reduction Reaction (ORR)." Materials 13, no. 7: 1562.

Review article
Published: 27 March 2020 in Trends in Food Science & Technology
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Colony plate counting still remains the “gold standard” procedure for the identification of viable Listeria monocytogenes cells and to address microbiological quality assurance of foodstuff. However, this classical method lacks sensitivity and also requires an analysis time superior to the current demands in food industry. Hence, new time-enhanced methods based on improved cultural techniques, nucleic acid detection and immunological assays have raised as new validated alternatives. Nevertheless, those rapid methods still require specific and expensive equipment and imply a considerable workload. In the last years, electrochemical biosensors and bioassays have been intensively investigated, emerging as excellent alternatives to surpass the disadvantages of the conventional and standard rapid methods. They provide the desired fast, sensitive and selective response, towards a portable, cost-effective and user-friendly performance. Therefore, in this work, a comprehensive review about the foundations, current achievements and limitations described over the past fifteen years for electrochemical biosensing of Listeria monocytogenes in food products is presented. The latest innovations rely on the use of low-cost electrochemical transducers, integration of novel (nano)materials and incorporation of new bioreceptors in the sensing strategy. Single-cell detection and intelligent packaging are also growing trends. Regardless of the remaining challenges, that still need to be overcome, electrochemical biosensing seems to have a role as one of the promising strategies to lead the future of foodborne pathogen analysis.

ACS Style

Nádia Silva; Marta M.P.S. Neves; Júlia M.C. S. Magalhães; Cristina Freire; Cristina Delerue-Matos. Emerging electrochemical biosensing approaches for detection of Listeria monocytogenes in food samples: An overview. Trends in Food Science & Technology 2020, 99, 621 -633.

AMA Style

Nádia Silva, Marta M.P.S. Neves, Júlia M.C. S. Magalhães, Cristina Freire, Cristina Delerue-Matos. Emerging electrochemical biosensing approaches for detection of Listeria monocytogenes in food samples: An overview. Trends in Food Science & Technology. 2020; 99 ():621-633.

Chicago/Turabian Style

Nádia Silva; Marta M.P.S. Neves; Júlia M.C. S. Magalhães; Cristina Freire; Cristina Delerue-Matos. 2020. "Emerging electrochemical biosensing approaches for detection of Listeria monocytogenes in food samples: An overview." Trends in Food Science & Technology 99, no. : 621-633.

Journal article
Published: 24 March 2020 in Antioxidants
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Chestnut processing industry generates large amounts of by-products, including leaves, burs and shells that are a source of bioactive compounds. The purpose of this study was to establish an ultrasound-assisted extraction (UAE) of phenolic and antioxidant compounds from industrial chestnut shells. A central composite design (CCD) was conducted to analyze the effects of time (4–46 min) and temperature (34–76 °C) in the antioxidant activity (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP)) and total phenolic compounds (TPC) of chestnut shells extracts. The optimal extraction conditions were obtained at 70 °C for 40 min. The optimal extract was characterized regarding phenolic profile, radical scavenging capacity, and effects on intestinal and dermal cell lines. The optimal extract revealed high amounts of ellagic acid (40.4 µg/mg dw), followed by caffeic acid derivative (15.4 µg/mg dw) and epigallocatechin (15.3 µg/mg dw). Indeed, the extract exhibited the highest scavenging efficiencies against NO● (IC50 = 0.1 µg/mL) and HOCl (IC50 = 0.7 µg/mL) and did not conducted to a decrease on HaCaT and HFF-1 viability up to 100 μg/mL. Oppositely, a decrease on Caco-2 and HT29-MTX viability was observed. This study suggests that UAE could be a sustainable option to valorize chestnut shells as raw material for different industries.

ACS Style

Fátima Lameirão; Diana Pinto; Elsa F. Vieira; Andreia F. Peixoto; Cristina Freire; Stefania Sut; Stefano Dall’Acqua; Paulo Costa; Cristina Delerue-Matos; Francisca Rodrigues. Green-Sustainable Recovery of Phenolic and Antioxidant Compounds from Industrial Chestnut Shells Using Ultrasound-Assisted Extraction: Optimization and Evaluation of Biological Activities In Vitro. Antioxidants 2020, 9, 267 .

AMA Style

Fátima Lameirão, Diana Pinto, Elsa F. Vieira, Andreia F. Peixoto, Cristina Freire, Stefania Sut, Stefano Dall’Acqua, Paulo Costa, Cristina Delerue-Matos, Francisca Rodrigues. Green-Sustainable Recovery of Phenolic and Antioxidant Compounds from Industrial Chestnut Shells Using Ultrasound-Assisted Extraction: Optimization and Evaluation of Biological Activities In Vitro. Antioxidants. 2020; 9 (3):267.

Chicago/Turabian Style

Fátima Lameirão; Diana Pinto; Elsa F. Vieira; Andreia F. Peixoto; Cristina Freire; Stefania Sut; Stefano Dall’Acqua; Paulo Costa; Cristina Delerue-Matos; Francisca Rodrigues. 2020. "Green-Sustainable Recovery of Phenolic and Antioxidant Compounds from Industrial Chestnut Shells Using Ultrasound-Assisted Extraction: Optimization and Evaluation of Biological Activities In Vitro." Antioxidants 9, no. 3: 267.

Research article
Published: 03 March 2020 in ACS Applied Energy Materials
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A bidirectional synergy involving Co-based polyoxometalates (POMs) incorporated in the Co-containing zeolitic imidazolate framework, ZIF-67, that promoted a notable improvement in the oxygen evolution reaction (OER) performance was unveiled for the first time. Two [email protected] nanocomposite materials—[email protected] and [email protected]—were successfully prepared via a room temperature ‘in situ’ approach, by the immobilization of POM anions [SiW9Co3(H2O)3O37]10− (SiW9Co3) in the cages of two isostructural ZIFs: ZIF-8 and ZIF-67, formed with Zn2+ and Co2+, respectively. Despite both [email protected] and [email protected] revealed similar and low occupancy degrees (ca. 6 POM units per 100 ZIF-cages), an intense synergy has been detected in the ZIF-67 based nanocomposite, while no synergistic interaction was found for POMs and ZIF-8. Due to this synergetic effect, the OER activity of [email protected] is significantly enhanced in comparison with that of ZIF-67: ~110 mV decreased overpotential and double current density. Additionally, this nanocomposite exhibits excellent stability in the alkaline electrolyte. Insights into the nature and magnitude of the SiW9Co3–ZIF-67 synergy have shown up its interesting ZIF ↔ POM bidirectional nature that involves activation of the Co-based active sites in POM clusters as a consequence of a ZIF-67 → SiW9Co3 electron transfer, along with POM-induced generation of more active unsaturated Co-nodes in the ZIF-67 frameworks. These findings represent a promising ‘proof of concept’ for the development of more efficient [email protected] electrocatalysts in the future.

ACS Style

Víctor Karim Abdelkader Fernández; Diana Mesquita Fernandes; Salete Balula; Luís Cunha-Silva; Cristina Freire. Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect. ACS Applied Energy Materials 2020, 3, 2925 -2934.

AMA Style

Víctor Karim Abdelkader Fernández, Diana Mesquita Fernandes, Salete Balula, Luís Cunha-Silva, Cristina Freire. Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect. ACS Applied Energy Materials. 2020; 3 (3):2925-2934.

Chicago/Turabian Style

Víctor Karim Abdelkader Fernández; Diana Mesquita Fernandes; Salete Balula; Luís Cunha-Silva; Cristina Freire. 2020. "Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect." ACS Applied Energy Materials 3, no. 3: 2925-2934.

Journal article
Published: 03 March 2020 in Molecules
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This study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.

ACS Style

Elsa F. Vieira; Cristina Soares; Susana Machado; M. Teresa Oliva-Teles; Manuela Correia; Maria João Ramalhosa; Ana Carvalho; Valentina F. Domingues; Filipa Antunes; Simone Morais; Cristina Delerue-Matos. Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements Composition. Molecules 2020, 25, 1133 .

AMA Style

Elsa F. Vieira, Cristina Soares, Susana Machado, M. Teresa Oliva-Teles, Manuela Correia, Maria João Ramalhosa, Ana Carvalho, Valentina F. Domingues, Filipa Antunes, Simone Morais, Cristina Delerue-Matos. Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements Composition. Molecules. 2020; 25 (5):1133.

Chicago/Turabian Style

Elsa F. Vieira; Cristina Soares; Susana Machado; M. Teresa Oliva-Teles; Manuela Correia; Maria João Ramalhosa; Ana Carvalho; Valentina F. Domingues; Filipa Antunes; Simone Morais; Cristina Delerue-Matos. 2020. "Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements Composition." Molecules 25, no. 5: 1133.