Browsing by Issue Date, starting with "2025-09"
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- Locust bean gum (LBG) – a potential excipient for inhalation purposes: excipient characterisation and in vitro and in vivo toxicological evaluationPublication . Pontes, Jorge Filipe; Guerreiro, Filipa; da Silva, Joana Pinto; Almeida, Maria; Rosso, Annalisa; Rosa da Costa, Ana M; Agusti, Géraldine; Lollo, Giovanna; Gaspar, Maria Manuela; Grenha, AnaDry powders proposed for lung drug delivery typically involve excipients not approved for inhalation. The physicochemical characterisation of excipients is informative regarding their interaction with different body structures. Locust Bean Gum (LBG) has been proposed for diverse applications, including inhalation, benefiting from targeting ability towards phagocytic cells owing to the presence of mannose moieties. The aim of the present study was to characterise the physicochemical parameters of LBG and, for the first time, draw a toxicological profile for this excipient. LBG from three different suppliers was evaluated and eventual changes on polymer characteristics induced by purification and microparticle production were assessed, which were observed to not occur. The commercial samples showed identical FTIR spectra, as well as TGA and DSC profiles, Mw around 3.60 × 106 Da, and Tg near − 39 ◦C. All microparticles presented similar morphology and Feret diameters around 4 μm. In vitro assays performed on respiratory (A549) cells evidenced no impact of LBG microparticles on cell viability (> 80 %) when biorelevant concentrations (≈ 0.1 mg/mL) were used. Additionally, inhalation of LBG microparticles by mice provided indications of a safe profile, without induction of allergic reactions. The basis is laid for further exploration of this material in inhalation.
- Metabolomics and proteomics of campomanesia pubescens fruits throughout developmental stagesPublication . Machado, Gilson Gustavo Lucinda; Costa, Carlos Alexandre Rocha da; Eller, Elda; Nascimento, Sidney Vasconcelos do; Nahon, Sayure Mariana Raad; Cavalcante, Alice de Paula de Sousa; Costa, Isa Rebecca Chagas da; Valadares, Rafael Borges da Silva; Carvalho, Elisângela Elena Nunes; Livramento, Kalynka Gabriella do; Vilas Boas, Eduardo Valério de BarrosThis study investigated the metabolic changes occurring during the ripening of Campomanesia pubescens fruits using metabolomics and proteomics approaches. Two alkaloids and nine phenolic compounds were identified, with emphasis on trigonelline and gallic acid. Proteomic analysis revealed 940 proteins, of which 452 showed differential expression, reflecting physiological changes, such as the reduced expression of ribulose-1,5- bisphosphate carboxylase/oxygenase, indicating low photosynthetic activity and the transition from chloroplasts to chromoplasts. The intensification of glycolysis was suggested by the increased expression of phosphoglycerate kinase and fructose-bisphosphate aldolase. The activation of enzymes of the phenolic compound pathway, such as phenylalanine ammonia-lyase and O-methyltransferase, indicated the accumulation of secondary metabolites essential for fruit defense and nutritional quality. The expression of enzymes in the ethylene pathway, such as SAM synthase, suggested their role in gabiroba ripening. The results highlight the interaction of metabolic pathways during fruit ripening.
- Physiological response of Palaemon elegans to multi-anthropogenic stressors: assessing the impact of marine heatwaves and UV filters contained in sunscreensPublication . Autiero, Alexandro; Martínez, Ico; Montesdeoca-Esponda, Sarah; Vinagre, Catarina; Gómez, May; Navarro, Alberto; Herrera, AliciaSunscreens UV filters have been identified as emerging pollutants, representing a toxic threat to aquatic environments. In addition to that, regions with intense sunscreen usage are usually exposed to marine heat waves. This study shows the combined effects of high-water temperatures associated with sunscreen exposure in Palaemon elegans (Rathke, 1836). A full factorial experiment tested two temperature conditions (20 and 32 degrees C) and two sunscreens (one eco-friendly and the other non-eco-friendly) over 12 h. Shrimp were exposed to both stressors and sampled after 30 min (T1), 6 h (T6) and 12 h (T12). At each sampling point, metabolic biomarkers (cytochrome c oxidase, electron transport system) and oxidative stress biomarkers (glutathione-S-transferase, superoxide dismutase, lipid peroxidation) were analysed in the muscle and hepatopancreas. In the muscle, metabolic biomarkers showed that at T12, ETS activity was upregulated, showing a high metabolic demand at elevated temperatures, 32 degrees C. Meanwhile, COX activity was downregulated, suggesting possible mitochondrial dysfunction due to the increased accumulation of reactive oxygen species (ROS), further enhanced by exposure to chemicals present in the non-eco-friendly sunscreen. LPO activity indicated the presence of oxidative stress in organisms exposed to high temperatures, 32 degrees C, in combination with the non-eco-friendly sunscreen. In contrast, oxidative stress biomarkers such as GST and SOD showed that these antioxidant defences function effectively at 20 degrees C, but their efficacy fails at 32 degrees C, probably due to significant ROS accumulation associated with elevated temperatures and chemical pollutants. UV filters accumulation over time and temperature was analysed using UHPLC. Results show that the concentration (mu g/g) of UV filters contained in the eco-friendly and non-eco. friendly sunscreens increased over time under higher temperature (32 degrees C). This indicates that marine heat waves can enhance the uptake of certain chemicals over just 12 h of exposure.
- Mitigation measures to reduce seabird's interactions with bottom-set nets in southern IberiaPublication . Frade, Magda; Carvalho, Flávia; Samel, Vighnesh Nilesh; Oliveira, Nuno; Andrade, Joana; Gonçalves, Jorge Manuel Santos; Marçalo, AnaBycatch poses a significant threat to seabird populations globally. On the southern coast of mainland Portugal, mitigation measures were tested to reduce seabird interactions with fishing vessels. Between 2021 and 2023, this study evaluated the effectiveness of a visual deterrent (a ’scarybird’ device), an acoustic deterrent (megaphone broadcasts), alongside modification in fisher’s behaviour discard management— avoiding discards during fishing operations to minimize seabird interactions. Observers monitored 166 fishing events, comparing control and experimental treatments. Discard management was the most effective deterrent, significantly reducing seabird abundance, particularly gulls (Larus spp.) and northern gannets (Morus bassanus). Model predictions indicated a 37 % and a 47 % reduction in the abundance of gulls and northern gannets, respectively, around commercial fishing vessels when discard management was used. This practice effectively kept a substantial proportion of birds away from the vessel during operations, thereby reducing their vulnerability to bycatch. The megaphone showed limited efficacy, with higher seabird abundance in treatment groups compared to controls. The scarybird device was largely ineffective in deterring gulls unless combined with discard management but showed potential in reducing interactions with northern gannets. Importantly, all mitigation measures did not negatively impact Landings Per Unit Effort (LPUE), which facilitated their acceptance among fishers. Our findings suggest that simple modifications in the fisher’s behaviour, such as retaining fish discards and viscera onboard, could serve as a promising bycatch mitigation measure, potentially eliminating the need for additional less effective mitigation devices that fishers may be reluctant to adopt.
- Photochemical treatment strategies for okadaic acid degradation: Effects of salinity, oxidants, and UV sourcesPublication . Moreno-Andrés, Javier; Lage, Sandra; Braga, Ana Catarina; Reis Costa, PedroThis study evaluates the degradation and detoxification of okadaic acid (OA), a marine biotoxin, through UVassisted photochemical processes using environmentally relevant OA concentrations. Experiments were conducted in distilled water (DW) and artificial seawater (ASW), applying two UV sources: UV-LED (lambda(max) = 275 nm) and low-pressure mercury lamp (LP-Hg; lambda = 254 nm), combined with hydrogen peroxide (HP), sodium peroxydisulfate (PDS), and potassium peroxymonosulfate (PMS). Photolysis alone was ineffective, and kinetic rate constants (k(obs); min(-1)) followed the trend UV/PMS > UV/PDS > UV/HP for both UV sources. While all treatments showed high OA removal (>79 %) in DW, degradation was significantly reduced for HP (72.8 %-89.9 %) and PDS (67.8 %-76.6 %) in ASW. In contrast, UV/PMS efficacy improved in saline media, achieving rapid and effective degradation of OA, and reaching 99 % detoxification (PP2A activity) within 15 min. The main transformation product, norokadanone (m/z 757.453), formed via decarboxylation, showed significantly reduced toxicity compared to OA. These results confirm the suitability of sulfate radical-based processes (particularly UV/ PMS) for OA mitigation in marine environments. In addition, this work highlights the critical role of water matrix composition in marine toxin treatment and supports the development of scalable, mercury-free strategies for effectively mitigating hazardous compounds in coastal environments.
- High-frequency glacial climate instability during the early pleistocene: insights from IODP site U1387 (Gulf of Cadiz)Publication . Trotta, Samanta; Duque Castaño, Monica Liliana; Rodrigues, Teresa; Voelker, Antje; Maiorano, Patrizia; Balestra, Barbara; Flores, José-Abel; Siniscalchi, Agata; Addante, Marina; Marino, MariaWe provide new high-resolution data on alkenone-derived sea surface temperature (SST) and calcareous plankton key taxa in temporally well constrained, high resolution benthic and planktonic oxygen isotope records at Integrated Ocean Drilling Program site U1387 in the Gulf of Cadiz. The investigated time interval encompasses the Early Pleistocene marine isotope stages (MIS) 48 to MIS 43. The aim is to evidence millennial climate variability during glacial phases of the “41 kyr world” and understand the impact of North Atlantic climate dynamics on the southern Portuguese margin. Neogloboquadrina pachyderma and Coccolithus pelagicus ssp. pelagicus record prominent, short-term abundance peaks concurrent with short-term SST minima and heavier values of ™18O in late MIS 48 and in the middle of MIS 46 and MIS 44. Superimposed on the obliquity and precession forcing, the wavelet analysis carried out on selected proxies (planktonic ™18O, N. pachyderma, C. pelagicus ssp. pelagicus, alkenone derived sea surface temperature) highlighted the occurrence of a higher frequency climate variability.