MARE - Comunicações em conferência com publicação em atas
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- Assessment of metal contamination levels and stress responses of endangered sea turtles of São Tomé and PrincipePublication . Morão, Inês F.; Novais, Sara C.; Vieira, Sara; Barata, Carlos; Piña, Benjamin; Lemos, Marco F.L.São Tomé Island harbors important sea turtle nesting and feeding sites. However, insufficient enforcement of environmental laws to avoid illegal take of nesting females and eggs, associated with a great lack of knowledge about how these species interact with their environment and how human activities impact their survival in the region, constitute significant challenges for sea turtle conservation. Through current local conservation projects, some information on genetics and nutrition of sea turtle populations is being unveiled but very little is known about how ocean pollution is impacting these turtles. The main objective of this study was to assess the metal concentrations accumulated by one species of S. Tomé sea turtles (Chelonia mydas) and infer about possible impacts of such contamination on their general stress responses and health status. More specifically, the final goal was to find correlations between metal concentrations and the expression of key genes involved in detoxification/sequestration and metal transport, antioxidant responses and oxidative stress, immunological responses, mitochondrial respiratory and energy production, among others, which could be indicative of these organisms health and future viability. To achieve these goals, nesting female turtles were sampled for blood, immediately after egg laying in their well-documented spawning sites in S. Tomé. Blood samples were withdrawn from the external jugular vein, a portion was stored in EDTA treated tubes at -20ºC until analysis of metal concentrations, and another portion was stored in RNAlater at -20°C until RNA extraction and gene expression analysis using quantitative real-time PCR (qPCR). Additionally, body mass and carapace length were also recorded, along with all information regarding egg spawning and its success. Results showed significant correlations between expression of some genes and metal contaminant levels, pinpointing some candidate genes to be used as biomarkers of interest for biomonitoring campaigns, which worrying function highlights the need for a close follow-up of these organisms. This study represents the first attempt to address pollutant levels and the biological impairments of such stressors in these turtle species nesting in S. Tomé which, given their classification as endangered species (IUCN red list), is of paramount importance to contribute for conservation measures and management.
- Assessment of traditional mayonnaise enriched with Aurantiochytrium sp. extractPublication . Pinheiro, Joaquina; Garcia, Adriana; Paulo, Maria; Coutinho, Joana; Baptista, Teresa; Bernardino, Susana M.; Tecelão, Carla; Gil, Maria M.; Lemos, Marco F.Mayonnaise, a food product widely consumed since the 1900s, traditionally prepared from a mixture of oil, egg yolk and vinegar, has a reduced shelf-life primarily due to lipid oxidation (Kwon et al., 2015). The addition of synthetic antioxidants like BHT (butylated hydroxytoluene), BHA (butylated hydroxyl anisole), and EDTA (ethylenediaminetetraacetic acid) has been used to control this problem (Gray, 1978). However, these synthetic antioxidants showed several disadvantages such as the easily decomposition at higher temperatures, and an increased health risk for chronic consumers (Martinez-Tome et al., 2001). Natural antioxidants, derived from marine algae, show great potential for improving oxidative stability, extending the shelf-life of stored food products with additional health-promoting benefits (Hermund et al., 2015). Since 2004, the DHA-rich oil derived from the microalgae Aurantiochytrium sp. has been recognized as safe, available for food use and for dietary supplements. In general, Aurantiochytrium sp. became a popular source of protein-rich biomass and of valuable compounds like pigments, antioxidants and essential fatty acids. The potential of heterotrophic microalgae Aurantiochytrium sp. as a source of functional ingredient applied in mayonnaise product has not been evaluated yet. The aim of this study was to evaluate the quality of mayonnaise enriched with Aurantiochytrium extract by colour (L*, a*, b*, and ºh), texture (hardness, adhesiveness, resilience, cohesion, springiness, gumminess, and chewiness) and antioxidant capacity (DPPH and total phenolics content). The mayonnaise without extract was used as control sample. Colour results indicated that the luminosity of mayonnaise enriched with extract increased and the a* and b* colour parameters decreased, promoting a colour enhancement. Also, with the addition of Aurantiochytrium extract, a decrease in all texture attributes obtained by TPA profile test, with exception of cohesion and springiness, was observed. A correlation between antioxidant activity and total phenolics content was denoted, in all samples. The high antioxidant capacity can be related to high radical scavenging activity, high total phenolic content, and high carotenoid content of the extract. This study demonstrates that Aurantiochytrium sp extracts have the potential to be used as a nutraceutical/functional ingredient in mayonnaise, a product widely consumed by different age groups.
- Berlengas Biosphere Reserve : plan for the assessment of ecosystem services and functionsPublication . Leandro, Sérgio; Marques, Daniel; Mouga, Teresa; Coelho, Helena; Rodrigues, Sandra; Maranhão, PauloThe project Berlengas Biosphere Reserve Plan for the Assessment of Ecosystem Services and Functions arises from the need to identify and assess ecosystem services, promoting sustainable uses of the services in the Reserve. The high degradation rate currently observed in the natural systems, thus reducing the level and quality of ecosystem services, is reflected in a negative effect on environmental quality, human wellbeing and in some economic activities. Thus, it becomes inevitable to promote the need to convey the importance of these services to society. It is also essential to contribute to the development of innovative and environmentally sustainable practices which will maintain the functioning of the local ecosystem and the sustainability of the services. Thus, the main goals of this project are i) to identify and analyse the impacts and dependencies on ecosystem services in the Reserve; ii) to analyse the trends of the priority services, iii) to identify the risks and opportunities associated with these services; iv) to evaluate their value and ultimately iv) to disseminate the results improving conservation and management. Based on the results to be obtained through the evaluation and maintenance of these services it is expected an improvement on the environment in the region and the development of efficient mechanisms for the management of resources. Started in February 2014, over the past 3 months much research has already been conducted, with emphasis for the identification of services and opportunities in the Reserve. Ecosystem services in Berlengas can range from simply providing essential goods or support (e.g. fish) to cultural services (e.g. field trips, diving). Work is also being done to develop, define and optimize the methods to assess ecosystems services trends and values.
- Bioactivity screening of Aurantiochytrium sp. for antioxidant activitiesPublication . Pinheiro, Joaquina; Garcia, Adriana; Paulo, Maria; Coutinho, Joana; Baptista, Teresa M.; Bernardino, Susana M.; Tecelão, Carla; Gil, Maria M.; Lemos, Marco F.L.Aurantiochytrium sp. is a heterotrophic microalgae that, in certain growth conditions, besides producing significant amounts of squalene, may potentially produce other bioactive compounds with high value and commercial interest such as docosahexaenoic acid (DHA), carotenoids, among others. Antioxidant compounds, naturally occurring in microalgae sources, have been identified as free radical or active oxygen scavengers, with beneficial effects on oxidation and oxidative damage inhibition in human body and foods. Several in vitro methodologies have been proposed to evaluate the antioxidant capacity, such as free radicals: 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), and reactive species including hydrogen peroxide (H2O2), singlet oxygen (O2), and superoxide anion (O2-) (Balboa et al., 2013). The main objective of the present study was to evaluate the antioxidant activity of aqueous and ethanolic extracts of Aurantiochytrium sp., by means of different methodologies: reducing and scavenging activity by total phenolics content (TPC, Singleton & Rossi, 1965), DPPH (Custódio et al., 2012), and oxygen radical absorbance capacity (ORAC, Dávalos et al., 2004). The obtained results indicated that the microalgae Aurantiochytrium sp. is rich in antioxidant compounds, by reducing activity through total phenolics and DPPH, as well as scavenging activity by ORAC. Moreover, it is evident the higher selectivity of ethanol as solvent for the extraction of antioxidants compounds. The potential of this microalgae biomass as a good, natural and sustainable source for use as a functional food ingredient is evident, representing an opportunity with additional benefits due to the antioxidant role in diseases prevention and treatment.
- Chemical characterization of fungal chitosan for industrial applicationsPublication . Cruz, Pedro; Vaz, Daniela C.; Ruben, Rui B.; Avelelas, Francisco; Silva, Susana; Campos, Maria
- O contributo das redes sociais para o desenvolvimento das Casas de Fado em AlfamaPublication . Simões, Sofia; Mendes, Susana; Carvalho, MárioOs turistas atualmente preferem o uso da internet e das redes sociais para pesquisar informações. O dinamismo dessas redes é uma ferramenta atrativa e de fácil utilização para os turistas. As redes sociais podem ser por isso um fator decisivo para influenciar as escolhas de acordo com a motivação dos turistas. O Fado, para além de ser uma marca de elevada notoriedade, assune-se também como o embaixador de excelência para o reforço da marca Portugal além-fronteiras. Este trabalho de investigação procura entender o contributo das redes sociais para o desenvolvimento das Casas do Fado em Alfama (Lisboa). Foi ainda estudada a intenção dos turistas em compartilhar as suas experiências nas redes sociais. Este trabalho foi estruturado em duas partes: revisão da literatura (1) e a aplicação de uma pesquisa (2) em várias Casas do Fado em Alfama. Assim, a pesquisa (n = 532) procurou perceber se os turistas quando frequentam as Casas de Fado utilizam as redes sociais para compartilhar as suas experiências. Os resultados expuseram algumas lacunas, nomeadamente evidenciaram a importância dos clientes partilharem as suas experiencias contribuindo assim para o aumento da promoção das Casas de Fado. Foi ainda possível observar o potencial das redes sociais para a criação de estratégias potenciando o desenvolvimento das Casas de Fado em Alfama.
- Cosmeceutical potential of crude extracts from Grateloupia turuturuPublication . Carmona, Ana M.; Félix, Rafael; Silva, Joana; Alves, Celso M.; Novais, Sara C.; Pedrosa, Rui P.; Lemos, Marco F.Biological invasions are recognised as a major global change and one of the most important threats to aquatic biodiversity and ecosystem integrity. Grateloupia turuturu is one of the 11 invasive macroalgae documented in Portugal and Galicia and its geographical span is growing every year. It has also been documented that this seaweed is a great source of polysaccharides, sulphated or not, presenting vast biotechnological opportunities. Under the scope of EU-funded project AMALIA – Algae-to-Market-Lab-IdeAs, and in an industry-focused approach, extractions of this alga were performed using low volumes of water and ethanol combined with short extraction times and different temperatures. The most promising extracts to be fitted into a cosmetic formulation with photoprotection activities, and collagenase and elastase inhibitory effects, were chosen after a Response Surface Methodology-based optimization of yield, in vitro antioxidant capacity, and UV-absorbance. The chosen extracts were then tested with a solar simulatorand using a 3T3 cell line for the assessment of their potential photoprotection activity. The same extracts were tested for the inhibitoryactivity of the enzymes collagenase and elastase, responsible for UV radiation-induced skin aging, showing promising activities in all the tests performed.
- Effect of different drying temperatures on the moisture, content of phytochemical constituents and technological properties of Peniche coast seaweedsPublication . Augusto, Ana; Nunes, Paulo M.; Mendes, Susana; Afonso, Clélia; Mouga, Teresa
- Effects of different drying conditions on the rehydration ratio and water holding capacity properties in three different species of algae Ulva lactuca, Codium vermilara and Codium tomentosumPublication . Rodrigues, Sidónio; Afonso, Clélia; Mouga, Teresa; Nunes, PauloOver the last years, algae have been increasingly used in Human food due their rich chemical and nutritional composition, particularly the high supply of essential nutrients to the human body such as protein and dietary fiber. Dietary fiber can be divided into two different types: soluble and insoluble. The characteristics of soluble dietary fiber are related to some physical and chemical properties such as rehydration ratio and water holding capacity and are important in assigning the functional and organoleptic properties and in preventing some human pathologies such as cardiovascular disease and obesity. The present study aimed to investigate the influence of different drying conditions on the rehydration ratio and water holding capacity of three green algae, Codium vermilara, Codium tomentosum and Ulva lactuca. The methods used for the determination of water retention capacity and rehydration ratio were similar to those used in previous studies (Susuki, T. et al., 1996). The algae were processed in a tray dryer and the drying conditions were: Temperature: 30ºC and 40ºC; Relative Humidity: 28%47% ; air velocity 1,9 m/s. In this work, it was concluded that higher drying temperature conditions originate lower rehydration ratio and consequent lower water holding capacity possibly due to a higher physical damage in the algae tissues. It was also observed that both Codium species have higher values for these two parameters than Ulva lactuca, under the same rehydration conditions.
- Environmental limits of low salinity to Gracilaria gracilis development. Where do we draw the line?Publication . França, Marcela; Afonso, Clélia; Baptista, Teresa; Pombo, Ana; Mouga, Teresa
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