Avaliação do efeito da aplicação de manoproteínas comerciais no incremento da qualidade de vinhos brancos

Face à exigência dos consumidores atuais, as características sensoriais de um vinho, assim como a sua estabilidade, são fatores determinantes para a sua aceitabilidade no mercado. A instabilidade proteica do vinho e consequente desnaturação/precipitação das proteínas depende de fatores (intrínsecos e extrínsecos) e é responsável pelo aparecimento de turvação nos vinhos brancos. Para prevenir a instabilidade proteica são usados vários produtos enológicos, com objetivo de remover as proteínas instáveis, no entanto com várias limitações, tais como eficiência e modificação das características físico-químicas e sensoriais no vinho. Nos últimos anos têm surgido diversos aditivos comerciais à base de manoproteínas, já que as mesmas podem ser uma via alternativa para a estabilização proteica do vinho. Neste trabalho foram selecionadas onze manoproteínas comerciais para avaliar o seu efeito na estabilização proteica, bem como o seu efeito na composição fenólica e nas características cromáticas e sensoriais num vinho branco. Os resultados obtidos mostraram que 9 das 11 manoproteínas testadas apresentaram efeito positivo na estabilização proteica do vinho. Além disso, todas as manoproteínas diminuíram o potencial de acastanhamento dos vinhos, e de um modo geral conduziram a um aumento da luminosidade. Na análise sensorial, apesar de não haver diferenças significativas relativamente ao vinho controlo, tendencialmente os vinhos mais pontuados foram os tratados com manoproteínas, nomeadamente ao nível da diminuição da cor, equilíbrio gustativo e na componente aromática, frutado e floral. Pelos resultados obtidos neste trabalho, podemos concluir que as manoproteínas parecem ser uma alternativa eficiente na estabilização proteica de vinhos brancos e que podem simultaneamente melhorar as características sensoriais do vinho, porém, convém salientar que estes resultados devem ser encarados como preliminares, sendo necessário realizar mais estudos com outros tipos de vinhos.info:eu-repo/semantics/publishedVersio

Estabilização proteica de vinhos brancos por adição de manoproteínas e impacto na qualidade

A instabilidade proteica é um defeito que pode conduzir à rejeição do vinho. A desnaturação e precipitação das proteínas instáveis, podem afetar a limpidez e/ou originar depósitos amorfos. A concentração e composição das proteínas, dependem da casta, condições climáticas, estado de maturação das uvas e da vinificação. A colagem com bentonite é o processo mais comum na prevenção desta instabilidade, mas apresenta limitações, particularmente quando aplicada em doses elevadas. Assim, têm sido estudadas alternativas, como por exemplo as manoproteínas

Electrochemical immunosensor for detection of CA 15-3 biomarker in point-of-care

This work reports the development of a simple and rapid electrochemical immunosensor for the determination of breast cancer biomarker Cancer Antigen 153 (CA153). Disposable and cost-effective chips, consisting of gold screen-printed electrodes (AuSPEs), were used to develop the portable electrochemical devices for monitoring the biomarker in point-of-care (PoC), under clinical context. The biosensor preparation consisted of two simple steps. First, a self-assembled monolayer (SAM) of mercaptosuccinic acid (MSA) was formed at the AuSPE surface. Then, the CA153 antibody was covalently bound to the carboxylic groups standing at the electrode surface using EDC/NHS chemistry. The performance of the developed immunosensor was evaluated by assessing the sensor sensitivity, linear response interval, selectivity and detection limit (LOD). The developed immunosensor provided a wide linear concentration range (from 1.0 to 1000UmL1) and low detection levels were achieved (LOD of 0.95UmL1), enabling the sensitive detection of the cancer biomarker at clinically relevant levels, using square wave voltammetry (SWV) as electroanalytical technique. Moreover, selectivity studies performed against other cancer biomarkers (CA 125 and CA 199) revealed that the antibody has high selectivity for CA15-3 antigen. The immunosensor was applied to the quantification of CA15-3 in artificial serum samples with satisfactory results.This research had the financial support of FCT (Fundação para a Ciência e Tecnologia) and co-financed by the European Union (FEDER funds) under the Partnership Agreement PT2020, Research Grants Pest-C/QUI/UIDB/00081/2020 (CIQUP) and NORTE-01-0247-FEDER-017834 (project RamSERS). J.A. Ribeiro (ref. SFRH/BPD/105395/2014) and C.M. Pereira (ref. SFRH/BSAB/150320/2019) acknowledge FCT under the QREN – POPH – Advanced Training, subsidized by European Union and national MEC funds.info:eu-repo/semantics/publishedVersio

Influence of structural features of mannoproteins in white wine protein stabilization

Proteins are presented in wine at low concentration, however these compounds could be responsible for colloidal instability and haze of wines.info:eu-repo/semantics/publishedVersio

Assessment of potential prebiotic activity of pineapple by-products (peels and stems) extracts and maintenance of bioavailability through in vitro gastrointestinal tract system

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Cx43 can form functional channels at the nuclear envelope and modulate gene expression in cardiac cells

Conexina 43; Expresión génica; Translocación nuclearConnexina 43; Expressió gènica; Translocació nuclearConnexin 43; Gene expression; Nuclear translocationClassically associated with gap junction-mediated intercellular communication, connexin43 (Cx43) is increasingly recognized to possess non-canonical biological functions, including gene expression regulation. However, the mechanisms governing the localization and role played by Cx43 in the nucleus, namely in transcription modulation, remain unknown. Using comprehensive and complementary approaches encompassing biochemical assays, super-resolution and immunogold transmission electron microscopy, we demonstrate that Cx43 localizes to the nuclear envelope of different cell types and in cardiac tissue. We show that translocation of Cx43 to the nucleus relies on Importin-β, and that Cx43 significantly impacts the cellular transcriptome, likely by interacting with transcriptional regulators. In vitro patch-clamp recordings from HEK293 and adult primary cardiomyocytes demonstrate that Cx43 forms active channels at the nuclear envelope, providing evidence that Cx43 can participate in nucleocytoplasmic shuttling of small molecules. The accumulation of nuclear Cx43 during myogenic differentiation of cardiomyoblasts is suggested to modulate expression of genes implicated in this process. Altogether, our study provides new evidence for further defining the biological roles of nuclear Cx43, namely in cardiac pathophysiology.This work was supported by the European Regional Development Fund (ERDF) through the Operational Program for Competitiveness Factors (COMPETE) under the projects HealthyAging2020 CENTRO-01-0145-FEDER-000012-N2323, CENTRO-01-0145-FEDER-032179, CENTRO-01-0145-FEDER-032414, EXPL/MED-OUT/0590/2021, UIDB/04539/2020 and PPBI-Portuguese Platform of BioImaging (POCI-01-0145-FEDER-022122). This work was also supported by the European Union's Horizon 2020 research and innovation programme under grant agreement MIA-Portugal no. 857524 and the Comissão de Coordenação da Região Centro (CCDRC) through the Centro2020 Program. T.A. acknowledges funding from Instituto de Salud Carlos III, grant PI16/00772 co-financed by the ERDF, and Fundación Científica Asociación Española Contra el Cáncer (IDEAS20039AASE). This work used the platforms of the Grenoble Instruct-ERIC center (ISBG; UAR 3518 CNRS-CEA-UGA-EMBL) within the Grenoble Partnership for Structural Biology (PSB), supported by FRISBI (ANR-10-INBS-0005-02) and GRAL, financed within the University Grenoble Alpes graduate school (Ecoles Universitaires de Recherche) CBH-EUR-GS (ANR-17-EURE-0003), and the Microscopy and Bioimaging Lab (iLAB) at the Faculty of Medicine of the University of Coimbra (Coimbra, Portugal). The IBS Electron Microscope facility is supported by the Auvergne Rhône-Alpes Region, the Fonds Feder, the Fondation pour la Recherche Médicale and GIS-IBiSA. Super-resolution microscopy experiments benefited from access to CBI/IGBMC (Illkirch, France) and were supported by FRISBI (ANR-10-INBS-0005). Financial support was provided by Instruct-ERIC (PID 14677)

Membrane technology for valorization of mango peel extracts

Mango peel is rich in nutritional and functional compounds, such as carbohydrates, dietary fibers, proteins, and phenolic compounds, with high potential to be applied in the food industry. Most of the investigation about recovery of bioactive compounds from fruit bioproducts involves extraction techniques and further separation of target compounds. There is still a lack of information about the potential of membrane processes to recover the nutritive/functional compounds present in aqueous extracts of those bioproducts. This research is addressed to study the performance of ultrafiltration (UF), followed by nanofiltration (NF) of UF permeates, to fractionate the compounds present in aqueous extracts of mango peel. Both UF and NF concentration processes were carried up to a volume concentration factor of 2.0. Membranes with molecular weight cut-offs of 25 kDa and 130 Da were used in the UF and NF steps, respectively. UF and NF concentrates showed antioxidant activity, attributed to the presence of phenolic compounds, with rejections of about 75% and 98.8%, respectively. UF membranes totally rejected the higher molecular weight compounds, and NF membranes almost totally concentrated the fermentable monosaccharides and disaccharides. Therefore, it is envisaged that NF concentrates can be utilized by the food industry or for bioenergy production

Production of bioactive protein-enriched hydrolysates from fish by-products using autohydrolysis

Protein demand is expected to double by 2050 [1]. The amount of by-products generated from the fish processing industry represents more than half of the entire fish weight. These materials are commonly discarded with high costs and environmental burden [1,2]. Giving their high protein content (57%, dry weight), fish- based by- and co-products could be used in the development and fortification of food and feed products, thus contributing to bioeconomy and sustainability. Hydrolysis has been widely used to extract protein from several matrixes and the resulting hydrolysates usually exhibit interesting bioactive and functional properties [3,4]. The present work aimed the production of bioactive protein-enriched hydrolysates from fish by-products, using water under subcritical conditions. For that, the raw material was homogenized and centrifugated at 8000 g and 4 ºC for 30 min. The resulting solid biomass was used for the hydrolysis experiments. Several temperatures (150 to 230 ºC) and times (5 to 30 min) were tested, using 20 g (dry weight) of biomass and 0.4 L of water. After the hydrolysis, the solubilization yields were determined and the hydrolysates were analysed for their chemical composition, peptide profiles (HPLC) and antioxidant activity (in vitro colorimetric assays). The solubilization yields increased with temperature and time of reaction. All hydrolysates presented antioxidant activity, being the best conditions at temperatures between 170 and 230 C. Moreover, all hydrolysates presented high protein content (up to 82%). Autohydrolysis proved to be an efficient method for the solubilization and hydrolysis of protein from fish by-products without the need for chemicals or expensive enzymes. Antioxidant hydrolysates with high protein content were produced, which could be useful in the development of and fortification of food and feed products and could be a possible path to a rational and integral use of scarce protein sources in the near future.The authors would like to thank Sebol - Comércio e Indústria de Sebo S.A. for providing the fish by-products. This work was financially supported by Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit Further support was obtained by Portugal 2020, European Structural and Investment Funds (ESIF) and Agência Nacional de Inovação, S.A. (ANI) under the scope of the project HeathyPETFOOD- PetFood formulations for promotion of health and quality of life (POCI-01-0247-FEDER-047073).info:eu-repo/semantics/publishedVersio

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

Estabilização proteica de vinhos brancos por adição de manoproteínas e impacto na qualidade

As proteínas, embora em reduzida concentração no vinho branco, podem ser fatores de instabilidade, e podem afetar a limpidez e/ou originar depósitos amorfos. Para prevenir a instabilidade proteica é tradicionalmente efetuada a colagem dos vinhos brancos com bentonite. Contudo, esta cola inorgânica apresenta algumas limitações, particularmente quando aplicada em doses elevadas. Neste contexto, foram avaliadas várias manoproteínas comerciais para a estabilização proteica dos vinhos, como possíveis alternativas à bentonite. Para o efeito caracterizaram-se onze manoproteínas, quanto à sua composição proteica e em açúcares. A sua eficácia foi avaliada relativamente ao seu potencjal de estabilização proteica, bem como ao seu efeito no potencial de acastanhamento, composição fenólica e nas características sensoriais do vinho