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Browsing ESTM - Artigos em revistas internacionais by Sustainable Development Goals (SDG) "12:Produção e Consumo Sustentáveis"
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- 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.
- 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.
- 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.
- CO-tucker: a new method for the simultaneous analysis of a sequence of paired tablesPublication . MENDES, SUSANA; Fernández-Gómez, M. José; Cotrim Marques, Sónia; Pardal, Miguel Ângelo; Azeiteiro, Ulisses Miranda; Galindo-Villardón, M. PurificaciónRelationships between species and their environment are a key com ponent to understand ecological communities. Usually, this kind of data are repeated over time or space for communities and their envi ronment, which leads to a sequence of pairs of ecological tables, i.e. multi-way matrices. This work proposes a new method which is a combined approach of STATICO and Tucker3 techniques and deals to the problem of describing not only the stable part of the dynamics of structure–function relationships between communities and their environment (in different locations and/or at different times), but also the interactions and changes associated with the ecosystems’ dynamics. At the same time, emphasis is given to the comparison with the STATICO method on the same (real) data set, where advan tages and drawbacks are explored and discussed. Thus, this study produces a general methodological framework and develops a new technique to facilitate the use of these practices by researchers. Fur thermore, from this first approach with estuarine environmental data one of the major advantages of modeling ecological data sets with the CO-TUCKER model is the gain in interpretability.
- Compounds altering fat storage in Daphnia magnaPublication . Jordão, Rita; Garreta, Elba; Campos, Bruno; Lemos, Marco; Soares, Amadeu M.V.M.; Tauler, Romà; Barata, CarlosThe analysis of lipid disruptive effects in invertebrates is limited by our poor knowledge of the lipid metabolic pathways. A recent study showed that tributyltin activated the ecdysteroid, juvenile hormone and retinoic X receptor signaling pathways, and disrupted the dynamics of neutral lipids in the crustacean Daphnia magna impairing the transfer of triacylglycerols to eggs and hence promoting their accumulation in post-spawning females. Tributyltin disruptive effects correlated with lower fitness for offspring and adults. The present study aims to addresses effects of existing compounds on storage lipids in post-spawning females and their health effects. D. magna individuals were exposed 12 chemicals that included vertebrate obesogens (tributyltin, triphenyltin, bisphenol A, nonylphenol, di-2-ethylhexyl phthalate), other contaminants known to affect arthropods (pyriproxyfen, fenarimol, methoprene, emamectin benzoate and fluoxetine), as well as the natural hormones methyl farnesoate and 20-hydroxyecdysone. Reproductive effects were also assessed. Quantitative changes in storage lipids accumulated in lipid droplets were studied using Nile red staining, which showed a close relationship with whole organism levels of triacylglycerols. Ten compounds altered storage lipids in a concentration related manner enhancing (tributyltin, bisphenol A, methyl farnesoate, pyriproxyfen and 20-hydroxyecdysone) or decreasing (nonylphenol, fenarimol, emamectin benzoate, methoprene and fluoxetine) their levels in post-spawning females. Eight compounds that altered lipid levels also had detrimental effects on growth and/or reproduction.
- Correlation between trace element concentrations in the blood of female hawksbill (Eretmochelys imbricata) and egg quality in nesting populations of São Tomé IslandPublication . Morão, Inês; Simões, Tiago; Busom Casado, Roger; Vieira, Sara; Ferreira-Airaud, Betânia; Caliani, Ilaria; Di Noi, Agata; Casini, Silvia; Fossi, Maria C.; Lemos, Marco F.L.; Novais, Sara C.Metals and metalloids can pose a significant threat to sea turtles, as these contaminants tend to accumulate in their bodies over time, due to their long lifespans and varied feeding habits. São Tomé and Príncipe's archipelago hosts the last remaining rookery for hawksbill sea turtles (Eretmochelys imbricata) in the region. The study aimed to determine the levels of metals and metalloids accumulated by this population and to investigate their possible genotoxicity in nesting females' blood as well as potential effects on their eggs in terms of morphometric characteristics and the quality of their lipidic reserves, essential for embryo development. Higher levels of Hg were found to be correlated with increased “lobed-shaped nuclei” in erythrocytic count, suggesting genotoxicity effects in this population. Higher levels of Se were correlated with thicker and heavier eggshells, while Pb levels were associated with the reduction of the egg's diameter. Metal contamination in females' blood significantly affected yolk polar fatty acids. Significant negative correlations were found between general metal contamination (PLI) and saturated fatty acids (SFA), while positive correlations were observed for essential omega-6 fatty acids (n6), mostly influenced by Cu, Fe, and Hg concentrations. This suggests that these omega-6 fatty acids are being synthesized from SFA, potentially indicating stress response by metal exposure. The present results point to some potential alterations in the normal embryonic development of these turtle eggs, influenced by metal contamination, which should raise some concerns about the future of this critically endangered species and call for additional conservation efforts in the region.
- Deep Eutectic Systems: A Game Changer for Marine Bioactives RecoveryPublication . Amador, Sandro; Martins, Alice; Matias, Margarida; Pedrosa, Rui; Pinteus, SuseteThe extraction of bioactive compounds from marine natural products has gained increasing attention due to their diverse applications, such as in pharmaceuticals, nutraceuticals, and cosmetics. Yet, low extraction yields and toxicity associated with common solvents are a major bottleneck. Deep eutectic solvents (DESs) and natural deep eutectic solvents (NADESs) have emerged as promising green alternatives to conventional organic solvents, offering advantages such as biodegradability, greater environmental and economic sustainability, low toxicity, and enhanced extraction selectivity. This review provides a comprehensive analysis of the principles, physicochemical properties, and applications of DESs/NADESs to obtain bioactive compounds from marine organisms. Among the most recent works, it is possible to verify the success of NADESs to extract carrageenan from the seaweed Kappaphycus alvarezii; pigments from Palmaria palmata; and polyphenols and proteins from different brown seaweeds. NADESs have also shown high potential to extract other valuable compounds from marine by-products, such as chitin from crabs and shrimp shells, and also lipids and proteins from different fish species and protein rich extracts from tilapia viscera. The challenges for DESs/NADESs use at industrial scale are also discussed, and success cases are revealed, highlighting their potential as game changers for extracting bioactive compounds from marine organisms and driving the development of innovative biotechnological products.