Unidade de Investigação - MARE – Marine and Environmental Sciences Centre
URI permanente desta comunidade:
Navegar
Percorrer Unidade de Investigação - MARE – Marine and Environmental Sciences Centre por Objetivos de Desenvolvimento Sustentável (ODS) "13:Ação Climática"
A mostrar 1 - 10 de 70
Resultados por página
Opções de ordenação
- 5-years after-Life Berlengas: Conservation efforts and monitoring in Berlengas Archipelago (2019-2024). Project LIFE Berlengas. SPEA - Portuguese Society for the Study of BirdsPublication . Oliveira, Nuno; Almeida, Ana; Alonso, Hany; Bouça, Alexandra; Costa, M.; Crisóstomo, Paulo; Leandro, Sergio Miguel; Mendes, R. N.; Morais, L.; Mouga, Teresa; Mourato, E.; Nascimento, T; Paiva, V. H.; Silva , C. Pereira da; Andrade, JO pós-LIFE Berlengas teve início em 2019. Neste relatório são apresentadas as tarefas realizadas durante 2019-2024, nomeadamente, monitorização e conservação de aves marinhas, biossegurança, controlo de plantas invasoras e monitorização da flora. Os resultados alcançados em termos de investigação, voluntariado, apoio, visitação e ações de sensibilização são também apresentados. A informação recolhida anteriormente ao pós-LIFE foi compilada de forma a apresentar todas as séries temporais disponíveis. Em termos de aves marinhas reprodutoras, foram monitorizados os tamanhos populacionais, a produtividade, as taxas de sobrevivência individual, seguimento individual, a ocupação dos ninhos artificiais e outras atividades de conservação. As espécies-alvo foram o roque-de-castro Hydrobates castro, a cagarra Calonectris borealis, a galheta Gulosus aristotelis, a gaivota-d'asa-escura Larus fuscus, a gaivota-de-patas amarelas Larus michahellis e o airo Uria aalge. Foram testadas medidas de mitigação para reduzir a captura acidental de aves marinhas e a interação com as pesca durante 229 dias de pesca. As aves terrestres reprodutoras e migradoras foram monitorizadas através de sessões de anilhagem e observações no terreno. Das 72 espécies observadas nas ilhas, foram anilhadas 20 espécies distintas. As medidas de biossegurança foram monitorizadas ao longo de cada ano na ilha da Berlenga. Não foram detetados sinais de roedores nas armadilhas A24 ©GoodNature nem nas caixas-rateiras. Apesar dos cinco alertas da potencial presença de roedores emitidos. As Berlengas continuam livres de roedores. No entanto foi feita a observação de fezes frescas de coelho-bravo Oryctolagus cuniculus em maio de 2024. Anualmente em abril, a vegetação foi monitorizada através de 75 quadrados de 2x2m. A cobertura e diversidade da vegetação aumentou ao longo dos anos, com 2024 a atingir o maior número de espécies registadas - 80. Foi monitorizada uma área de exclusão de gaivota-de-patas-amarelas durante a primavera. Foram observadas diferenças significativas entre as subáreas, com maiores abundâncias de Armeria berlengensis na subárea de exclusão, quando comparada com a área de não exclusão. Os novos rebentos de chorão Carpobrotus edulis foram removidos das áreas intervencionadas no âmbito do LIFE Berlengas, o que resultou num esforço anual de monitorização de 466 pessoas*hora. Desde 2019, foram publicados 16 artigos em revistas científicas. Entre 2019 e 2024, 71 voluntários estiveram envolvidos nos trabalhos das Berlengas. A SPEA implementou 4 projetos para assegurar as tarefas do Pós-LIFE. A visitação na ilha da Berlenga foi monitorizada anualmente. As melhorias que decorreram incluíram a implementação da Capacidade de Carga Humana e a plataforma de acesso à ilha da Berlenga. A câmara "ninho ao vivo" esteve ativa ao longo de todo o período, transmitindo imagens em tempo real a partir de um ninho de cagarra e de um ninho de roque-de-castro, em alternado. Foram desenvolvidas diversas ações para sensibilização e de educação ambiental pela SPEA e ICNF. Tais atividades tiveram como público-alvo os visitantes da ilha da Berlenga, os pescadores de Peniche, grupos internacionais, operadores marítimo-turísticos, professores e alunos das escolas locais.
- Anti-Hepatocellular Carcinoma (HepG2) Activities of Monoterpene Hydroxy Lactones Isolated from the Marine Microalga Tisochrysis LuteaPublication . Gangadhar, Katkam N.; Rodrigues, Maria João; Pereira, Hugo; Gaspar, Helena; Malcata, F. Xavier; Barreira, Luísa; Varela, JoãoTisochrysis lutea is a marine haptophyte rich in omega-3 polyunsaturated fatty acids (e.g., docosahexaenoic acid (DHA)) and carotenoids (e.g., fucoxanthin). Because of the nutraceutical applications of these compounds, this microalga is being used in aquaculture to feed oyster and shrimp larvae. In our earlier report, T. lutea organic crude extracts exhibited in vitro cytotoxic activity against human hepatocarcinoma (HepG2) cells. However, so far, the compound(s) accountable for the observed bioactivity have not been identified. Therefore, the aim of this study was to isolate and identify the chemical component(s) responsible for the bioactivity observed. Bioassay-guided fractionation through a combination of silica-gel column chromatography, followed by preparative thin layer chromatography (PTLC), led to the isolation of two diastereomers of a monoterpenoid lactone, namely, loliolide (1) and epi-loliolide (2), isolated for the first time in this species. The structural elucidation of both compounds was carried out by GC-MS and 1D (1 H and13 C APT) and 2D (COSY, HMBC, HSQC-ed, and NOESY) NMR analysis. Both compounds significantly reduced the viability of HepG2 cells and were considerably less toxic towards a non-tumoral murine stromal (S17) cell line, although epi-loliolide was found to be more active than loliolide. © 2020 by the authors.
- Assessement and management of environmental quality conditions in marine sandy beaches for its sustainable use—Virtues of the population based approachPublication . Gonçalves, Sílvia C.; Marques, João C.Sandy beaches constitute high natural value ecosystems which have been worldwide a target for growing human activities and ensuing pressures in the last decades, which caused ecological damages on these environments and led to its environmental quality decline. However, little is known about the responses of these ecosystems to distinct stressors and pressures, and holistic and integrated coastal management actions that protect beach environments and their ecological processes are yet to be developed. The aim of this viewpoint article is to present and discuss the utility of using a population approach to macrofaunal key species as a helpful tool for the assessment, management, and sustainable use of sandy beaches. The role of macrofaunal key species as indicators of environmental changes and of ecological quality condition is discussed and illustrated by some practical examples from the literature. The population is presented as a highly relevant ecological unit in management and one of the easiest ones to use, responding more rapidly to disturbances in the ecosystem than the most complex units. In this context, bio-ecology and population dynamics models are presented as tools and their potential, to improve the way we assess and manage ecological quality conditions of beach ecosystems aiming at its sustainable use, are discussed. Also, the advantages and drawbacks of the use of these tools in the population approach are evaluated. Monitoring, assessment and management practices focusing on beach key species bioecology as ecological indicator hold large potential in nowadays fast changing scenario, and should be encouraged as a function of their identifiable responses to manmade and natural disturbances.
- Assessing Ecological Quality on the Rocky Coast of Abalo Beach, PortugalPublication . Mouga, TeresaPortugal’s rich marine biodiversity, home to approximately 550 seaweed species, is distributed across biogeographical regions influenced by Atlantic and Mediterranean climates. Human-induced stressors, including habitat degradation, pollution, and climate change, have impacted seaweed ecosystems, changed the distribution patterns and promoting the invasion of alien species. This paper evaluates the ecological dynamics of seaweed communities on the rocky coast of Abalo Beach, Portugal, using the Marine Macroalgae Assessment Tool (MarMAT) in 2022 and 2023. The MarMAT methodology, endorsed by the Portuguese Environment Agency, assesses the ecological quality of coastal areas based on taxonomic composition, diversity, and biomass of macroalgae. The assessment revealed different percentages of late-successional species (ESGI) and annual (ESGII) seaweeds, indicating a subtle decrease in late-successional species. Of concern is the increase in invasive species from one in 2009 to six in 2023, suggesting a potential threat to ecosystem integrity. Comparative analysis with previous studies confirms the ongoing ecolog ical quality and resilience of Abalo Beach. The article underscores the importance of continuous monitoring amid environmental changes and the rise of invasive species.
- Bifurcaria bifurcata: a key macro‐alga as a source of bioactive compounds and functional ingredientsPublication . Alves, Celso; Pinteus, Susete; Simões, Tiago; Horta, André; Silva, Joana; Tecelão, Carla; Pedrosa, RuiThe aim of this work was to study the proximate composition and the bioactive profile of Bifurcariabifurcata. It contains 73.31 0.69% of moisture, 8.57 0.11 g per 100 g dry weight (d.w.) of protein,5.81 0.14 g per 100 g d.w. of lipid content and 30.15 0.00 g per 100 g d.w. of ash. The polyunsatu-rated fatty acids were the most abundant fatty acid (FA), accounting for 2426.56 mg per 100 g which rep-resents 41.77% of the total FA. The methanolic fraction showed high quantity of polyphenols (220.01 0.010 phloroglucinol equivalents g 1 extract), DPPH radical reduction capacity (EC 50:58.82 lg mL 1)and oxygen radical absorbent capacity (3151.35 119.33 lmol Trolox equivalents g 1 extract). Thehighest antimicrobial effect was observed against Pseudomonas aeruginosa (11.3 1.5 mm) and Sac-charomyces cerevisiae (IC 50 :17.07 lg mL 1 ) induced by methanolic and dichloromethane fractions,respectively. Dichloromethane fraction revealed the highest antitumor activity on Caco-2 and HepG-2 cells. Bifurcaria bifurcata can be a promising source of bioactive compounds and functionalingredients.
- Bioaccumulation and Elimination of Waterborne Mercury in the Midge Larvae, Chironomus riparius Meigen (Diptera: Chironomidae)Publication . Azevedo-Pereira, Henrique M. V. S.; Abreu, Sizenando N.; Lemos, Marco F.L.; Soares, Amadeu M. V. M.Here, mercury kinetics and behavioural effects in the midge larvae under a water-only exposure were assessed. Uptake and elimination of waterborne mercury were described by using a one-compartment kinetic model. Results show that midges were able to readily accumulate the heavy metal (BCF = 450), presenting a fast uptake, up to 13.1 lg Hg g of animal-1 at the end of the exposure period. Elimination was slow, with c.a. 39 % of the mercury in larvae being depurated after 48 h in clean medium. Behaviour did not present differences upon exposure or elimination, but a trend to increase ventilation was noticed during the exposure period.
- Bioproducts from forest biomass II. Bioactive compounds from the steam-distillation by-products of Cupressus lusitanica Mill. and Cistus ladanifer L. wastesPublication . Tavares, Cláudia S.; Martins, Alice; Miguel, M. Graça; Carvalheiro, Florbela; Duarte, Luís C.; Gameiro, José A.; Figueiredo, A. Cristina; Roseiro, Luísa B.Obtaining essential oils and hydrolates from underutilized biomass is an economic and sustainable way for production of these high added-value bioproducts. However, this process still generates large amounts of residues as the by-products obtained during distillation, which can be a concern for the environment, but also adequate substrates for other applications. Considering this fact, the waste distilled by-products remaining after steam-distillation of underutilized biomass from Cupressus lusitanica and Cistus ladanifer, were evaluated as a natural source of other high value products with biological activities, namely, phenolic compounds. Thus, the remaining extracted solid residues (ESRs) were characterized and subject to further treatments by ultrasound-assisted extraction (UAE) with ethanol and 70 % acetone, in order to prepare phenolic-rich extracts thereof: ESRs(EtOH) and ESRs(70 % Ace). Together with the distiller condensation waters (DCWs), these extracts were characterized for their phenolic content (total phenols, tannins and flavonoids). Their antioxidant activity was also evaluated by different methodologies. The phenolic profile of DCWs, ESRs(EtOH) and ESRs(70 % Ace) from both waste species was obtained by capillary zone electrophoresis (CZE) and phenolic compounds were tentatively identified. Results obtained for C. lusitanica biomass are here disclosed for the first time. Generally, all samples revealed to be rich in phenolic compounds, being C. ladanifer biomass the one with higher phenolic content. DCWs presented values of 140 mgGAE/g for C. lusitanica and 210 mg GAE/g for C. ladanifer, from which ca. 60 % were tannins. Extracts obtained with 70 % acetone were the ones with the highest results, except for the antioxidant activity by xanthine oxidase and superoxide inhibition, which was higher in DCWs. Catechins were the major compounds found for both species, but gallocatechins and gallic acid were only identified in C. ladanifer. Hydroxycinnamic acid derivatives and salicylic acid were also identified in C. ladanifer, partly justifying the anti-inflammatory effect referred for this species.
- Bioremediation of Synthetic Wastewater with Contaminants of Emerging Concern by Nannochloropsis sp. and Lipid Production: A Circular ApproachPublication . Santos, Bruna; Araújo, Juliana; Carvalho, Beatriz; Cotrim, Carolina; Bernardino, Raul; Freitas, Filomena; Sobral, Abílio J. F. N.; Encarnação, TelmaContaminants of emerging concern (CECs) pose a potential risk to human and environmental health. Microalgae bioremediation is a promising approach for transforming or removing contaminants from the environment, while contributing to the circular economy. In this study, Nannochloropsis sp. was effectively used for the simultaneous removal of six CECs: paracetamol, ibuprofen, imidacloprid, methylparaben and bisphenol A at 10 µg mL−1 and triclosan at 0.5 µg mL−1 from synthetic wastewater, which were able to survive under such concentrations, higher than those commonly found in the environment (up to 2.82 µg mL−1 of methylparaben). High removal efficiencies were reached for methylparaben (100%) and bisphenol A (93 ± 2%), while for imidacloprid, paracetamol and ibuprofen, 30 ± 1%, 64 ± 2% and 49 ± 5% were removed, respectively. Subsequently, lipids were extracted, and the FAME profile was characterised using GS-MS. The main fatty acids identified after bioremediation were hexadecadienoic acid isomers (C16:2), palmitic acid (C16), linoleic acid (C18:2) and γ-linolenic acid (C18:3). The absence of oleic acid and stearic acid was noticed, suggesting an alteration in the lipidic profile due to contaminant exposure. By exploring the quantification of fatty acids in future work, potential applications for the extracted lipids can be explored, further demonstrating the feasibility of this circular process.
- Broodstock conditioning of the Portuguese oyster (Crassostrea angulata, Lamarck, 1819): influence of different dietsPublication . Anjos, Catarina; Baptista, Teresa; Joaquim, Sandra; Mendes, Susana; Matias, Ana Margarete; Moura, Paula; Simões, Tiago; Matias, DomitíliaThe Portuguese oyster Crassostrea angulata shows great potential in oyster farming. The conservation of pure populations of this species is important for production diversification and biodiversity preservation. In this way, the zootechnological development for seed hatchery production is extremely important. Broodstock conditioning is a key step in the process of rearing bivalves in a hatchery. Many factors regulate the reproductive cycle, being food one of the most important ones. To evaluate the effect of different diets on C. angulata reproductive performance, broodstock were conditioned with different food regimes formulated fundamentally by flagellates (Diet 1 – Pavlova lutheri and Isochrysis galbana clone T-ISO; Diet 2 – P. lutheri, T-ISO and Skeletonema costatum) and constituted fundamentally by diatoms (Diet 3 – S. costatum and Chaetoceros calcitrans; Diet 4 – P. lutheri, S. costatum and C. calcitrans). During conditioning, samples of oysters were collected to evaluate condition index, gonadal development and biochemical composition. At the end of the conditioning period, oysters were induced to spawn to evaluate reproductive output (fecundity, fertilization rate and D-larvae development). The diets had an impact on the gametogenesis process, energy storage and reproductive output performance, being the best results those obtained in broodstock fed with the diatoms-predominant diets. However, those fed with diets majority flagellates had an unsuccessful performance. Holistic approaches incorporating all results in this study reveal and reinforce the idea that the diatom species used presented the nutritional requirements to C. angulata broodstock, being essential in the conditioning phase.
- Camelina oil as a source of polyunsaturated fatty acids for the production of human milk fat substitutes catalyzed by a heterologous Rhizopus oryzae lipasePublication . Faustino, Ana Rita; Osório, Natália M.; Tecelão, Carla; Canet, Albert; Valero, Francisco; Ferreira‐Dias, SuzanaThis study aims to produce human milk fat substitutes (HMFS) rich in polyunsaturated fatty acids (PUFA),mainly the essential omega-3 linolenic acid, by acidolysis reaction between tripalmitin (PPP) and free fattyacids (FFA) from camelina oil, in stirred batch reactor and solvent-free media. The non-commercialheterologous Rhizopus oryzae lipase (rROL), immobilized on Lewatit VP OC 1600 or on Relizyme OD403/S, and the immobilized commercial lipase from Rhizomucor miehei (Lipozyme RM IM) were tested asbiocatalysts. Both lipases are sn-1,3 selective. After 24 h reaction at 60°C, using biocatalyst loads of 5 wt%(in relation to tripalmitin), 48.9, 43.6, and 18.3 mol% of fatty acid incorporation in triacylglycerols (TAG)were obtained with Lipozyme RM IM and rROL immobilized on Lewatit or on Relizyme, respectively.rROL immobilized on Lewatit was selected as biocatalyst for the acidolysis, as alternative to the commercialimmobilized lipases. With this biocatalyst, the molar incorporation increased with its initial water activity(0.55–0.95). Modeling acidolysis catalyzed by rROL immobilized on Lewatit was performed by responsesurface methodology, as a function of temperature (58–72°C) and molar ratio FFA:PPP (1.2:1–6.8:1). Thehighest PPP consumption was achieved at 60°C with a molar ratio of 2:1. The yield of HMFS (new TAG)increased from 42.6 wt% (5% biocatalyst load) to 52% with 8% load, after 24 h acidolysis.Practical applications: Camelina oil showed to be a good source of PUFA, mainly essential fatty acids,to incorporate in HMFS. After 24 h acidolysis under optimized conditions, catalyzed by the non-commercial sn-1,3 regioselective rROL immobilized on Lewatit VP OC 1600, the TAG fraction contains67.7 mol% of palmitic acid at position 2. These structured lipids rich in PUFA can be used in blends with1,3-dioleoyl-2-palmitoyl-glycerol (OPO) in order to mimic the human milk fat. The performance of thisbiocatalyst was comparable to that observed with Lipozyme RM IM. The replacement of high-costcommercial immobilized lipases by rROL immobilized on Lewatit may reduce the biocatalyst cost. Inaddition, since the best molar ratio FFA:PPP for rROL is 2:1, i.e., the stoichiometric value for theacidolysis catalyzed by sn-1,3 regioselective lipases, the use of this biocatalyst will reduce downstreamcosts related with unconverted FFA recovery.