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- Effects of dietary supplementation with macroalgae on sperm quality and antioxidant system in Senegalese solePublication . Félix de Azeredo Pinto e Melo, Francisca; Silva, Nádia; Oliveira, Catarina; Cabrita, Elsa; Gavaia, PauloWithin the efforts in the search for novel feed ingredients in aquaculture, macroalgae are being widely explored due to their diversity of bioactive compounds with considerable prophylactic and therapeutic potential. Plocamium cartilagineum and Sargassum vulgare, have the potential to positively impact fish health, mainly due to their antioxidant properties. The production of Senegalese sole (Solea senegalensis) still faces some constraints due to the low sperm quantity and quality of males from captivity, which is highly affected by oxidative stress. We hypothesized that the scavenger ability of P. cartilagineum and S. vulgare could ameliorate the reproductive performance of Senegalese sole males, once incorporated in the roodstock feeds. In this experiment, broodstock groups were fed with three different formulated experimental diets for 60 days: Control (Ctrl), a diet supplemented with 5% P. cartilagineum (Pc), and a diet supplemented with 5% S. vulgare (Sv). Fish were sampled twice to evaluate sperm quality using different techniques: sperm motility by Computer Assisted Sperm Analysis (CASA) software, and cell viability and Reactive Oxygen Species (ROS) by flow cytometer. At the final sampling, 6 fish per treatment were sacrificed and gonads were extracted to determine the relative expression of anti- and pro-apoptotic genes (bcl2b, bcl-x, mcl1b, badb, bax, boka), and genes involved in fish antioxidant system (sod3, cat, gpx, hsp70). Sex steroids were measured on blood plasma by ELISA. Specific growth rate (SGR) and feed efficiency were also evaluated at the end of the experiment. Senegalese sole breeders fed with Pc diet for 60 days showed enhanced sperm total motility and cell viability at the end of the experiment, when compared with the Ctrl diet. On the other hand, fish fed with Sv diet had lower spermatozoa intracellular ROS and upregulated gpx in the gonads. No differences were obtained in levels of sex steroids and gonadal apoptotic system after 60 days of feeding, however, the macroalgae species and the percentages of incorporation used proved to positively modulate different spermatozoa traits.
- 4-hydroxyquinolin-2(1H)-one isolated in cryogenic argon and xenon matrices: tautomers and photochemistryPublication . Secrieru, Alina; Lopes, S.; Nikitin, T.; Cristiano, Maria de Lurdes; Fausto, R.4-Hydroxyquinolin-2(1H)-one (4HQ2O) was synthesized, isolated in cryogenic matrices (argon and xenon), and studied by infrared spectroscopy. Quantum chemical calculations carried out at the DFT(B3LYP)/6-311++G (3df,3pd) level of theory were used to determine the conformational and tautomeric properties of the molecule. Two tautomeric forms were identified in the as-deposited matrices with the help of the theoretical data. To investigate the photochemistry of the compound, in situ broadband ultraviolet (lambda > 283 nm) irradiation of the asdeposited argon matrix was performed. This irradiation led to the generation of an additional tautomer, together with the products of fragmentation of the heterocyclic ring of the molecule, specifically isocyanic acid and carbon monoxide. Photoproducts such as 1,3-dihydro-2H-indol-2-one and cyclohepta-1,2,4,6-tetraene were also observed in the photolyzed argon matrix. A comprehensive assignment of the infrared spectra of all the species observed experimentally is presented.
- Examination of the effects of excess microalgae availability on the disruption of mussel byssus secretionPublication . Ji-Yue Ni; Yan Zhou; Yu-Qing Wang; Shi-Hui Huang; Qian-Wen Cui; Wen-Yi Wang; Xiao-Ying Yang; Power, Deborah Mary; Yi-Feng LiThe present study evaluated the effects of food availability on byssus secretion in the hard-shelled mussel Mytilus coruscus. Byssus production was evaluated, and foot tissue transcriptomes, the site of byssus production, were generated. The results showed that byssus secretion was disrupted in mussels fed high levels of microalgae (HFL, 88.8 mg/L day−1), compared to the control group (p < 0.05), and that more byssus production occurred in the HFL group during the recovery period. Byssus secretion was not affected in mussels fed low levels of microalgae (8.88 × 10−3 mg/L day−1), but the shedding of byssus filaments was significantly increased compared to the control mussels (p < 0.05). Transcriptome data of the foot tissue revealed that lysosome, FoxO signaling, and autophagy pathways involved in autophagic cell death and apoptosis were significantly affected (p < 0.05) and may explain differences in byssus growth under modified food availability in M. coruscus. High feed levels modified metabolic pathways, such as sphingolipid, tyrosine, and phenylalanine, and downregulated genes coding for mussel foot proteins, which may explain reduced byssus production. The study found that contrary to expectation increased food availability reduced mussel byssus production by altering foot metabolism and promoting autophagy of foot tissue.
- Participatory development and management of eco-cultural trails in sustainable tourism destinationsPublication . Lukoseviciute, Goda; Henriques, Cláudia Helena; Nobre Pereira, Luis; Panagopoulos, ThomasRecent trail development has been motivated by sustainable tourism destination principles, suggesting a paradigm incorporating an eco-cultural trail concept. As with conventional trails, eco-cultural trail destination governance necessitates coordinated development and management of all landscape elements, emphasizing and protecting cultural and natural assets. This research aims to provide a sustainable strategy for developing ecocultural trails, applying a qualitative approach and stakeholder participation. Two focus groups and a workshop were conducted involving stakeholders representing governmental agencies, private enterprises, academic experts, students, and environmental organizations. A case study trail “Seven Hanging Valleys” was used in this study to develop an eco-cultural trail development and management strategy. Natural and cultural landscapes, trail infrastructure, trail visitor experience, and marketing and collaboration were the examined dimensions. Based on stakeholders’ visions, a destination development and management plan was established, aligning the environmental objectives to preserve natural and cultural assets, with improved overall experience for travellers and the community. Management implications: - Community collaboration provides trail managers and policymakers with a framework that identifies the essential levels of investment, programming, and management required to assist trails in becoming more economically and socially driven. - The proposed management plan for eco-cultural trails can assist landscape managers with indicated management priorities when developing eco-cultural trails that aim to respect natural and cultural assets and provide memorable trail-related experiences. - The process of creating a stakeholders’ shared vision for the sustainable development of the trail site provides trail managers with a better understanding of existing and future threats and allows them to future-proof trail maintenance and service plans.
- Insights into core molecular changes associated with metamorphosis in gilthead seabream larvae across diverse hatcheriesPublication . NAJAFPOUR, BABAK; Santos, Soraia; Manchado, Manuel; Vidal, Aurora; Tsipourlianos, Andreas; Canario, Adelino; Moutou, Katerina A.; Power, Deborah MaryEarly development is a critical period in fish aquaculture and is influenced by biotic and abiotic factors (e.g., temperature, feed) that can vary significantly between hatcheries, making it difficult to identify core factors determining quality. Many of the existing larval transcriptome studies are small-scale and occur under specific rearing conditions that do not mirror the diversity of larviculture practices at an industrial level. In the present transcriptome study, gilthead seabream at the larval to juvenile transition (metamorphosis) from several hatcheries in Europe (Greece, Italy, and France) were analysed in a large-scale RNA-seq study. The aim was to uncover the most significant molecular modifications occurring during metamorphosis, irrespective of differences in biotic or abiotic factors, to address knowledge gaps associated with critical early developmental stages under industrial hatchery conditions. Commonly modified gene transcripts between larval stages were identified based on the clustering of gene expression profiles of 25 gilthead seabream libraries from different hatcheries in a PCA analysis. When larvae at flexion were compared to larvae at mid-metamorphosis, 2243 differentially expressed genes (DEGs) were identified, and when larvae at early to mid-metamorphosis were compared to mid to late-metamorphosis, 2299 DEGs were identified. Comparative analysis across the developmental stages of gilthead seabream revealed genes of importance for the metamorphic transition and adaptation to rearing conditions, including genes related to the nervous system at flexion (24 days post hatch), enteroendocrine cell differentiation, and lipid homeostasis at early to mid-metamorphosis (46 dph), and enrichment of genes indicative of immune competence at mid to late-metamorphosis (51-54 dph). The differential expression of some endocrine-associated genes, dio1, dio2, cldn1, ing4, Pou3f4, and fgf22, highlights their importance in metamorphosis. Meta-analysis of the transcriptomes from two species, the gilthead seabream and Senegalese sole, that have differing symmetry and ecology uncovered common molecular expression patterns that underlie larvae maturation during metamorphosis, and we propose that these represent core gene markers of metamorphosis in these two fish species.
- Habitat suitability of two flagship species, hippocampus hippocampus and Hippocampus guttulatus, in the Atlantic coast of the Iberian Peninsula - implications for conservationPublication . Peiffer, Friederike; Lima, André Ricardo Araujo; Henriques, Sofia; Pardal, Miguel A.; Martinho, Filipe; Gonçalves, Jorge Manuel Santos; Gonçalves, Emanuel J.; Correia, Miguel; Silva, Gonçalo Jorge FrancoAnthropogenic pressures on marine ecosystems are increasing worldwide, causing loss of biodiversity and ecosystem functioning, and driving species towards risk of extinction. To protect vulnerable species and habitats, Marine Protected Areas (MPAs) are increasingly established worldwide as conservation measures. Seahorses act as flagship species for coastal ecosystem conservation due to their charismatic appearance and high vulnerability to habitat degradation. Here, the habitat suitability of the two European seahorse species, Hippocampus hippocampus and Hippocampus guttulatus, was assessed along the western Iberian Peninsula, using an ensemble species distribution modelling approach. Furthermore, the coverage of their core habitat (relative habitat suitability (HS) ≥ 0.5) with MPAs was estimated. The results show that the main drivers for habitat suitability were distance to the coast, aspect of the seafloor, tidal amplitude, and temperature. However, the importance differed between the two species. The suitable habitat of H. hippocampus extended to higher distances to the coast, while H. guttulatus were mostly restricted to areas in the vicinity of the coast and facing away from the open sea (i.e., the westerly aspect of the seafloor). Furthermore, temperature contributes more to the variation in habitat suitability in H. hippocampus than in H. guttulatus. The areas with the highest habitat suitability are estuarine or inlet waters and sheltered coasts in northwestern Spain, central and south of Portugal. Both species’ core habitats are covered by about 19–20 % with implemented protected areas in Portugal. In comparison, there is less coverage for both species in Spain, with 12 % for H. guttulatus and 6 % for H. hippocampus. Besides, zones of full protection cover less than 0.5 % of the core habitat while the rest of the protected areas provide only moderate to low restrictions and do not specifically address the protection of seahorses in their management plans. The results provide useful information on the distribution and the different habitat preferences of the two species, indications for further monitoring of populations, and recommendations for efficient spatial conservation areas that can protect the species and other associated vulnerable species and habitats.
- Life cycle assessment of integrated multi-trophic aquaculture: a review on methodology and challenges for its sustainability evaluationPublication . Hala, Ahmad Furqan; Chougule, Komal; Cunha, Maria; Caria Mendes, Madalena; Oliveira, Inês; Bradley, Tom; Forbes, Jonathan; Galileu Speranza, LaisThe increase in aquaculture activity is inevitable to fulfil global food provisioning for a growing population. Therefore, it is most recommendable to develop a sustainable approach for aquaculture practice. Integrated Multi-Trophic Aquaculture (IMTA) is proposed as one solution taking advantage of circular uptake of nutrients within the system. IMTA practice has been conducted for a thousand years despite only gaining recognition in recent decades. It is suggested to have lower environmental impact while promoting more advantages in the social and economic aspect of the industry. Therefore, multi aspects perspective of Life Cycle Assessment (LCA) is valuable to demonstrate the benefits of the system compared to the others. This review analyses 29 LCA studies on IMTA systems from 2009 to 2022 to understand the results, challenges, limitations, and benefits of LCA methodologies on IMTA systems. The studies followed the ISO 14040/44 guideline and were selected using the Google Scholar research tool. The four stages of the LCA were evaluated and it was concluded that there are several challenges in the Goal and Scope definition phase to determine the functional unit and methods that will be utilized. Hence, it is valuable to evaluate more options and, whenever possible, to conduct sensitivity analysis to help determine the proper methodology. The development of a specific database for the aquaculture sector is also strongly recommended, together with a standardized methodology for Data Collection and definition of impact categories to improve the consistency and comparability of the studies. Feed, fish effluents, and energy use are the impact hotspots and improving these factors might decrease the total impacts of the system as well. From this review, the potential of IMTA systems compared to monoculture systems and the potential of applying a tool such as LCA to measure it is highlighted. Therefore, more studies need to be conducted to improve the LCA methodology's consistency and reliability for IMTA system assessment.
- Electrical impedance spectroscopy for potassium content analysis and botanical origin identification of honeyPublication . Elamine, Youssef; INÁCIO, PEDRO; Miguel, Maria da Graça; Carlier, Jorge; Costa, Maria Clara; Estevinho, Leticia M.; Gomes, Henrique L.Minerals are reported to dominate the electrical properties of honey and indicate its botanical and geographical origins. In this study, Electrochemical Impedance Spectroscopy (EIS) was used to assess the relation between mineral elements, electrical properties and botanical origin using three honey varieties - Citrus sp., Eucalyptus sp., and Erica sp. These varieties are identified through pollen analysis and market labelling. Flame atomic absorption and emission spectroscopies were used to quantify the concentrations of eight elements (potassium, sodium, calcium, magnesium, manganese, zinc, copper, and iron). Among all the mineral elements, potassium showed a consistent correlation with impedance. The potassium estimation in honey and standard solutions (calibration curve) had similar sensitivities of 153.43 nF/mM and 132.68 nF/mM, respectively. Additionally, the analysis revealed that potassium dominates the mineral composition, with the other species present in minimal quantities. The EIS technique showed high sensitivity to potassium and other ionisable species, making it possible to classify the botanical origin of these three honey types. The EIS technique proved to be both time and cost effective, yielding a classification rate higher than that achieved by analysing mineral composition.
- Are mixtures of micro/nanoplastics more toxic than individual micro or nanoplastic contamination in the clam ruditapes decussatus?Publication . Ventura, Emma; Ribeiro Gonçalves, Joanna Melissa; Vilke, Juliano Marcelo; d'Errico, Giuseppe; Benedetti, Maura; Regoli, Francesco; Bebianno, MariaThe abundance of micro (MPs) and nano (NPs) sized plastic particles in the ocean is concerning due to their harmful effects on marine life. The interactions between MPs and NPs in the marine environment and their impact on marine biota remain not fully understood. This study contributes with new insights into the interaction between polystyrene NPs (PSNPs) and polyethylene MPs (PEMPs) on the clam Ruditapes decussatus . Results showed ingestion of MPs and NPs by clams, with PSNPs demonstrating higher toxicity in hemolymph. While no genotoxicity was observed, clams treated with MPs and the mixture showed increased acetylcolinesterase (AchE) activity over time. Additionally, the antioxidant defense system mitigated oxidative stress, suggesting effective neutralization of reactive oxygen species. Hazard assessment indicated the greatest impact on clam digestive glands after ten days of exposure, with an antagonistic interaction between MPs and NPs noted.
- Global microplastic fiber pollution from domestic laundryPublication . Wang, Chunhui; Song, Jing; Nunes, Luís; Zhao, Hongting; Wang, Peng; Liang, Zhirong; Arp, Hans Peter H.; Li, Gang; Xing, BaoshanThe rapid expansion of fast fashion has significantly increased microplastic fiber (MPF) release during laundry practices, accounting for approximately one-third of primary microplastics entering the ocean. Currently, a significant gap exists in global-scale research on the release of MPFs from washing textiles. This study introduces an innovative empirical model to assess the spatial distribution of MPF emissions. The model estimates an annual global emission of 5.69 million tons of MPFs from laundry. Of this total, machine washing accounts for the majority (93.7 %), with hand washing contributing the remaining 6.3 %. As the primary source of MPF pollution, Asia's ' s emissions reach 3.71 million tons, far exceeding those of North America (1.18 million tons) and Europe (0.45 million tons). The primary issue is that wastewater management efficiency varies significantly worldwide. In Asia, there is persistently high discharge of MPFs into natural waters, and the removal efficiency of wastewater treatment plants is still comparatively low. In contrast, the United States and many European countries exhibit better MPF retention. The global nature of this challenge mandates international collaboration for comprehensive environmental conservation. Our study provides the first high-resolution global distribution map of MPF emissions and discharge into natural waters, establishing a data foundation for global and regional management of microplastics originating from household laundry sources.