Screening of Phaeodactylum tricornutum extracts regarding their bioactive and functional properties

The expanding interest in addressing a more sustainable and eco-friendlier product development regarding the problem of ecological preservation results in a growing community search for bioactive natural-based formulations. Microalgae extracts potential for their interesting bioactive properties has been widely recognized, with antioxidant activity accounting for a major application in cosmetics, pharmaceutics and nutrition fields, due to its health-promoting effects. Moreover, microalgae generally contain large amounts of structural biopolymers, which might possibly display interesting rheological properties. This work was designed to enhance microalgae potential biotechnology exploration by attaining at least two different main fractions, namely with bioactive and texturizing functions. Phaeodactylum tricornutum was used under a biorefinery concept, by performing extractions with several solvent systems with a wide polarity spectrum. Previous work enhanced this microalgae species potential as an antioxidant agent, regardless of the antioxidant quantification method used, when compared to Nannochloropsis oceanica and Chlorella vulgaris extracts. P. tricornutum powdered biomass was extracted (4% dry weight) using water or hydroethanolic mixtures (25-96%) under same conditions of extraction, namely, over one hour at three different temperatures: 40ºC, 60ºC and 80ºC. All extracts were screened for their bioactive potential by three different antioxidant activity measurement assays: FRAP, ABTS and DPPH, as well as chemical characterized regarding their phenolic and pigment content. Lipidic fraction was evaluated for ethanol 25%, 50% and 96% extracts. Rheological properties and emulsifying capacity and stability were determined for water and ethanol 25% extracts, while protein and carbohydrate content were also assessed. Overall, findings from this study suggest that P. tricornutum extracts have a great potential for biotechnology purposes: aqueous extracts were particularly interesting for their functional properties while bioactive properties were more relevant for the ethanolic extracts. These may due to a higher protein and carbohydrate fraction present in more aqueous extracts. On the other hand, extracts with higher concentration of ethanol evidenced a greater amount of pigments, phenolics and lipids. In this manner, further studies should be fulfilled in order to explore their application in natural-based product formulation.This work was supported by the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of UID/BIO/04469/2020 unit. This study has also received funding from the European Fund for Regional Development (FEDER), COMPETE 2020 – Competitiveness and Internationalization Operational Program (Portugal 2020) and the European Regional Development Fund (Algarve 2020 and Lisboa 2020), under the scope of the project AlgaValor (grant agreement nº POCI-01-0247-FEDER-035234; LISBOA-01-0247-FEDER-035234; ALG-01-0247-FEDER-035234).info:eu-repo/semantics/publishedVersio

Screening of Phaeodactylum tricornutum extracts regarding theirbioactive and functional properties

The expanding interest in addressing a more sustainable and eco-friendlier product development regarding the problem of ecological preservation results in a growing community search for bioactive natural-based formulations. Microalgae extracts potential for their interesting bioactive properties has been widely recognized, with antioxidant activity accounting for a major application in cosmetics, pharmaceutics and nutrition fields, due to its health-promoting effects. Moreover, microalgae generally contain large amounts of structural biopolymers, which might possibly display interesting rheological properties. This work was designed to enhance microalgae potential biotechnology exploration by attaining at least two different main fractions, namely with bioactive and texturizing functions. Phaeodactylum tricornutum was used under a biorefinery concept, by performing extractions with several solvent systems with a wide polarity spectrum. Previous work enhanced this microalgae species potential as an antioxidant agent, regardless of the antioxidant quantification method used, when compared to Nannochloropsis oceanica and Chlorella vulgaris extracts. P. tricornutum powdered biomass was extracted (4% dry weight) using water or hydroethanolic mixtures (25-96%) under same conditions of extraction, namely, over one hour at three different temperatures: 40ºC, 60ºC and 80ºC. All extracts were screened for their bioactive potential by three different antioxidant activity measurement assays: FRAP, ABTS and DPPH, as well as chemical characterized regarding their phenolic and pigment content. Lipidic fraction was evaluated for ethanol 25%, 50% and 96% extracts. Rheological properties and emulsifying capacity and stability were determined for water and ethanol 25% extracts, while protein and carbohydrate content were also assessed. Overall, findings from this study suggest that P. tricornutum extracts have a great potential for biotechnology purposes: aqueous extracts were particularly interesting for their functional properties while bioactive properties were more relevant for the ethanolic extracts. These may due to a higher protein and carbohydrate fraction present in more aqueous extracts. On the other hand, extracts with higher concentration of ethanol evidenced a greater amount of pigments, phenolics and lipids. In this manner, further studies should be fulfilled in order to explore their application in natural-based product formulation.This work was supported by the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of UID/BIO/04469/2020 unit. This study has also received funding from the European Fund for Regional Development (FEDER), COMPETE 2020 – Competitiveness and Internationalization Operational Program (Portugal 2020) and the European Regional Development Fund (Algarve 2020 and Lisboa 2020), under the scope of the project AlgaValor (grant agreement nº POCI-01-0247-FEDER-035234; LISBOA-01-0247-FEDER-035234; ALG-01-0247-FEDER-035234).info:eu-repo/semantics/publishedVersio

The balance between treatment efficiency and receptor quality determines wastewater impacts on the dissemination of antibiotic resistance

This study investigated the balance between treatment efficiency and impact caused by urban wastewater treatment plants (UWTPs) on the dissemination of antibiotic resistance. Four full-scale UWTPs (PT1-PT4) and the receiving river were sampled over four campaigns. The 16 S rRNA gene, two mobile genetic elements (MGEs), eight antibiotic resistance genes (ARGs), and culturable bacteria were monitored over different treatment stages and in hospital effluent. The bacterial and antibiotic resistance load was not significantly different in the inflow of the four UWTPs (p > 0.01). Biological treatment promoted ARGs reduction values up to 2.5 log-units/mL, while UV (PT1, PT2) or sand filtration/ozonation (PT3) led to removal values < 0.6 log-units/mL. The final effluent of PT3, with the highest removal rates and significantly lower ARGs abundance, was not significantly different from the receiving water body. Emerging ARGs (e.g., blaVIM, blaOXA-48, and blaKPC) were sporadically detected in the river, although more frequent downstream. Hospital effluent might contribute for the occurrence of some, but not all these ARGs in the river. A major conclusion was that the impact of the UWTPs on the river was not only determined by treatment efficiency and final effluent quality, but also by the background contamination of the river and/or dilution rate.info:eu-repo/semantics/publishedVersio

Monitoring antibiotic resistance genes by qPCR or metagenomics analyses: high sensitivity versus broad coverage?

info:eu-repo/semantics/publishedVersio

Deciphering a multi-event in a non-complex set of detrital zircon U–Pb ages from Carboniferous graywackes of SW Iberia

The determination of U–Pb ages from detrital zircons of sedimentary rocks using LA-ICP-MS has been widely used for the purpose of provenance analysis. One problem that frequently arises is finding a population that appears to be non-complex despite several perceptible age peaks in its spectrum. These peaks are qualitatively defined by means of relative probability diagrams, or PDFs, but it is difficult to quantify their statistical significance relative to a zircon forming multi-event. Thus, can a multi-event in a non-complex set of detrital zircon U–Pb ages be deciphered and characterized? The aim of this study is to attempt to provide an answer to this question by means of statistical analysis. Its objectives are: a) to determine the best minimum number of zircon age populations (peaks), BmPs, b) for the characterization of each peak in terms of age and event duration; c) to compare the results obtained from two datasets showing similar zircon ages; and d) to demonstrate the usefulness of deciphering these BmPs. First, cluster analysis is carried out, aimed at grouping zircon ages into a set of consistent clusters. A Gaussian Kernel function is then fitted to each cluster and summed to obtain a theoretical PDFm (modeled probability density function). Finally, the selected modeled PDFm (that built on the BmPs) is that which reports the lowest number of peaks for which the difference as compared with the original gPDF (global probability density function) is equal to or below 5%. Deciphered BmP peaks can be characterized and used for characterizing and providing an understanding of related event(s). A geological interpretation, based on the results obtained, is attempted. This includes a robust measure for maximum age of deposition for both Cabrela and Mértola graywackes

Methodologies and Applications Review

Funding Information: The Authors acknowledge Fundação para a Ciência e a Tecnologia (FCT-MCTES) for its financial support via the project UIDB/00667/2020 (UNIDEMI). Pedro M. Ferreira also acknowledges FCT-MCTES for funding the PhD grant UI/BD/151055/2021. Publisher Copyright: © 2022 by the authors.Sensing Technology (ST) plays a key role in Structural Health-Monitoring (SHM) systems. ST focuses on developing sensors, sensory systems, or smart materials that monitor a wide variety of materials’ properties aiming to create smart structures and smart materials, using Embedded Sensors (ESs), and enabling continuous and permanent measurements of their structural integrity. The integration of ESs is limited to the processing technology used to embed the sensor due to its high-temperature sensitivity and the possibility of damage during its insertion into the structure. In addition, the technological process selection is dependent on the base material’s composition, which comprises either metallic or composite parts. The selection of smart sensors or the technology underlying them is fundamental to the monitoring mode. This paper presents a critical review of the fundaments and applications of sensing technologies for SHM systems employing ESs, focusing on their actual developments and innovation, as well as analysing the challenges that these technologies present, in order to build a path that allows for a connected world through distributed measurement systems.publishersversionpublishe

Granting Sensorial Properties to Metal Parts through Friction Stir Processing

The authors would like also to thank to Micronsense-Metrologia Industrial (Leiria, Portugal) for the μCT analysis. The authors would also like to thank Prof. Catarina Santos for granting access to the MicroLab - Electron Microscopy Laboratory (Instituto Superior Técnico) for the SEM analyses.Structural Health Monitoring systems assess the part's current condition. This can be performed with a monitoring system comprising sensors, on the surface or embedded, in the monitored parts. However, surface sensors are subject to damage, and embedding the sensors may result in a weakened part. An innovative Self-Sensing Material and its manufacturing process were developed and are presented herein. As proof of concept, Barium Titanate particles were introduced and dispersed into an AA5083-H111 part by Friction Stir Processing (FSP). The particles’ distribution and concentration was evaluated by a set of characterization techniques, demonstrating that greater concentrations, grant enhanced sensitivity to the material. The use of FSP and the embedded particles improved the part’s mechanical behaviour in the processed zone. The sensorial properties were assessed and the response to a set of dynamic loads was measured, being coherent with the solicitations provided. The developed self-sensing material revealed an electrical sensitivity of 12.0 × 10-4 uV/MPa.publishersversionpublishe

Dynamics of carbapenem resistance in urban wastewater treatment plants and receiving water bodies: drivers and opportunities for action

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Time-trends in human immunodeficiency virus infection in Portugal: 1984-2013

Avaliaram-se tendências temporais da infeção pelo vírus da imunodeficiência humana (VIH) em Portugal. Calcularam-se incidência (1984-2013), prevalência e mortalidade por VIH (1988-2013). Com modelos de regressão linear segmentada obteve-se percentagem de variação anual (%VA) e intervalo de confiança a 95% (IC95%) para esses parâmetros, identificando-se anos (pontos de inflexão) em que ocorreram mudanças significativas na tendência. A incidência aumentou até 1999 (homens) e 2000 (mulheres) e depois diminuiu de 47 para 20/100000 homens e de 15 para 8/100000 mulheres até 2013, com decréscimo significativo desde 2003 em homens (%VA=-3,1;IC95%:-4,3;-1,9) e 2000 em mulheres (%VA=-2,8;IC95%:-4,1;-1,6 até 2010 e %VA=-11,3;IC95%:-18,5;-3,6 após 2010). O pico para a mortalidade ocorreu em 1996, decrescendo de 19 para 7/100000 homens e de 4 para 2/100000 mulheres durante 1996-2013, com declínio significativo desde 2003 em homens (%VA=-7,1;IC95%:-8,6;-5,6) e 1996 em mulheres (%VA=-2,9%;IC95%:-4,1;-1,7). A prevalência aumentou significativamente até 2013 para 0,4% (homens) e 0,2% (mulheres), mas com redução gradual da %VA entre pontos de inflexão. O maior declínio da incidência observou-se em utilizadores de drogas injetáveis (UDI) decrescendo de 17 para 1/100000 habitantes durante 1997-2013. Em heterossexuais decresceu de 12 para 8/100000 durante 2002-2013 mas em homossexuais aumentou até 2011 estabilizando em 4/100000. Portugal apresenta progresso favorável relativamente ao controlo da infeção com redução drástica da infeção entre UDI

Heterocyclic aromatic amines formation in grilled fatty fish

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