Browsing by Issue Date, starting with "2025-03"
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- Testis transcriptomic analyses reveal the effects of an algae feed on sperm quality in senegalese sole during the breeding seasonPublication . Félix de Azeredo Pinto e Melo, Francisca; Raposo de Magalhães, Cláudia; Marrero Alemán, Carlos; Duarte, Daniel Filipe Correia; Parente, Pedro; Fatsini Fernández, Elvira; Oliveira, Catarina; Cabrita, ElsaThe usage of dietary algae antioxidants to improve fish reproduction is under-explored, especially in terms of the male reproductive system. In this experiment, 6 % of a blended meal of Phaeodactylum tricornutum and Gracilaria gracilis was incorporated in Senegalese sole broodstock feed, to evaluate the effects on sperm quality of F1 males throughout the breeding season. For that, two groups of breeders were fed during 6 months with the control and algae diets (6 % of control wheat meal replaced with 6 % algae blend). Every 2 weeks, fish were sampled for sperm quality evaluation, which included spermatozoa motility (CASA system), lipid peroxidation (MDA quantification), cell viability, reactive oxygen species (ROS), apoptotic status (flow cytometer), and DNA fragmentation (Comet assay). On a final sampling, 6 fish per group were sacrificed to dissect gonadal tissue, extract RNA and perform an RNA sequencing (RNA-seq) for each treatment. Sperm quality variability was high during the breeding season, including within the same month, irrespective of the diet. Cell viability was approximately 80 % during the whole experiment. Nonetheless, in specific sampling points, algae-fed fish showed higher spermatozoa protection against oxidative processes: in the 1st sampling live cells without ROS (%) were 3 times higher than in control group; on the last two samplings, spermatozoa showed half of MDA content; and on the 3rd sampling had less DNA fragmentation. No differences were found regarding apoptotic status. At the end of the reproductive season, gonadal transcriptomic analysis revealed that algae-fed fish were lacking stimuli for sperm production, both in terms of quantity and quality. This fish group seemed to have lipid metabolism and antioxidant capacity enhanced by the diet but, at the same time, were facing a compensatory mechanism due to an unknown algae compound that might be disrupting DNA replication and spermatogenesis. Altogether, this study suggests that algae blends can be used in broodstock feeds for Senegalese sole, however further research is needed to understand how to use only the desirable bioactive compounds and thus obtain higher and consistent sperm quality throughout the breeding season.
- Piggery wastewater treatment by solar photo-Fenton coupled with microalgae productionPublication . Ferreira, Alice; Belachqer-El Attar, Solaima; Villaró-Cos, Silvia; Ciardi, Martina; Soriano-Molina, Paula; López, José Luis Casas; Lafarga, Tomás; Marques-dos-Santos, Cláudia; Acién, Gabriel; Gouveia, LuisaPig farming generates highly polluted wastewater that requires effective treatment to minimize environmental damage. Microalgae can recover nutrients from piggery wastewater (PWW), but excessive nutrient and turbidity levels inhibit their growth. Solar photo-Fenton (PF) offer a sustainable and cost-effective pretreatment to allow microalgal growth for further PWW treatment. This study optimized the concentrations of PF reagents to minimise water and nutrient inputs while maintaining microalgae-based treatment efficiency. PF trials were conducted in pilot-scale raceway ponds under solar radiation, testing different concentrations of FeSO4 (4.48 and 8.95 mM) and H2O2 (77, 154, and 309 mM). Following PF, Tetradesmus obliquus was used in a biological treatment of PWW to recover the remaining nutrients. PF achieved high removal efficiencies for turbidity (97.6-99.5 %), total organic carbon (59.2-77.1 %), and chemical oxygen demand (83.8-94.7 %), but ammonium was not significantly removed. Phosphorus was almost completely removed through iron precipitation during neutralisation. Lowering the H2O2 concentration from 309 to 77 mM did not compromise removal efficiency but reducing FeSO4 below 8.95 mM negatively affected the process. Consequently, 8.95 mM FeSO4 and 77 mM H2O2 were selected for microalgae production. The pretreated PWW could be recycled at least once for microalgal production, without nutrient supplementation, improving biomass productivity and PWW treatment, especially targeting ammonium. Phosphorus supplementation, however, did not significantly boost biomass productivity or treatment efficiency. Moreover, the iron sludge generated from PF pretreatment contained enough NPK to be repurposed as an organic fertilizer boosting sustainable agricultural practices. These findings encourage further investigation of this emerging combined technology towards wastewater treatment at large-scale.
- Cryopreservation did not affect spermatogonia global methylation profile in Senegalese sole (Solea senegalensis)Publication . Almeida, Maria Mafalda; Cabrita, Elsa; Laizé, Vincent; Brionne, Aurélien; Labbé, Catherine; Fatsini Fernández, ElviraSpermatogonia cryopreservation is a method to preserve valuable genomes from both maternal and paternal origin. The damage associated with the application of this technology on post-thaw cell quality is important to assess, including at the epigenetic level. This study aimed to assess post-thawed spermatogonia quality by evaluating alterations in plasma membrane integrity, DNA integrity (fragmentation and apoptosis), lipid peroxidation (malondialdehyde levels) and epigenetic modifications (DNA methylation profile). We observed that plasma membrane integrity (fresh 78.98 % f 5.66; cryopreserved 62.81 % f 3.25; P = 0.003) and DNA integrity (fresh 32.95% f 2.28; cryopreserved 37.28% f 1.87; P = 0.0026) were affected by cryopreservation, while no difference in lipid peroxidation was observed (fresh 1.13 % f 0.45; cryopreserved 0.91 % f 0.96; P = 0.701). While global levels of DNA methylation were unaffected by cryopreservation (fresh 82.80 % f 0.47; cryopreserved 83.32 % f 0.81; P = 0.745), some differentially methylated cytosines (DMC) were observed in cryopreserved versus fresh spermatogonia (156 DMC). This study showed that spermatogonia cryopreserved according to our protocol provides a good supply of undamaged cells for several applications. The significance of the few detected DMCs deserves further attention since it may affect gamete differentiation and epigenetic profile.
- Inhibitory potency of active metabolites from different polarities of Datura Stramonium seed extracts: GC-MS analysis, biological evaluations, and molecular docking studiesPublication . Hjouji, K.; El Barnossi, A.; Er-rajy, M.; Atemni, I.; Grenha, Ana; Yagoubi, M.; Ainane, T.; Taleb, M.; Rais, Z.Datura Stramonium is a well-known and important medicinal plant that is widely used in various medical systems to treat conditions such as asthma, diabetes, and inflammatory diseases. The aim of this study was to prepare extracts of D. stramonium seeds in different solvent polarities for assessing phytochemical potential, in vitro biological activities, and molecular docking studies. Phytochemical screening was conducted to determine the phytochemical composition, while GC-MS analysis was used to identify secondary metabolites of D. Stramonium. The seed extracts were molecularly docked to evaluate bioactive and antioxidant activity. The minimum inhibitory concentration (MIC) of the extracts against bacteria such as S. aureus, E. coli, Bacillus subtilis, and Proteus mirabilis was determined. Antifungal activity was also tested against fungi including Aspergillus fl avus, Fusarium oxysporum, Aspergillus niger, and Candida albicans. The results of phytochemical screening indicated that the primary plant constituents in all extracts of different polarities are alkaloids, flavonoids, tannins, mucilage, sterols, heterosides, triterpenoids, and cardiac glycosides. Most molecules in the hexane, ether, and chloroform extracts consist of fatty acids, sterols, glycosides, triterpenoids, alkaloids, and phenolic compounds, as revealed by GC-MS analysis. Conversely, extracts from polar solvents like methanol, ethanol, and water are abundant in alkaloids. In vitro antibacterial and antifungal activities demonstrated that ether, methanol, and ethanol extracts were more effective than inhibiting the four bacterial strains compared to the antibiotics Oxacillin and Cefuroxime. The ether and methanol extracts exhibited better zones of inhibition and significant MIC values against A. niger and C. albicans compared to the control and fluconazole. The free radical inhibition (DPPH) (24.92 5.31 m g/mL) for the ethanol extract indicates Datura's antioxidant capacity. It is believed that the main phytochemicals are responsible for the enhanced antioxidant activity observed in other studies. The docking study revealed that the bioactive compounds linoleic acid and atropine formed better hydrogen bonding interactions with proteins than pi-alkyl and alkyl bonds. (c) 2024 SFMM. Published by Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
- Digestive and metabolic consequences of on-growing greater amberjack (Seriola dumerili) juveniles at different temperatures. In-vivo and ex-vivo assessmentPublication . Navarro-Guillén, C.; Perera, E.; Pérez-Hilario, D.; Martos-Sitcha, J.A.; Molina-Roque, L.; Gregorio, Silvia; Fonseca, Filomena; Fuentes, J.; Yúfera, M.Aiming to elucidate the effects of temperature on different aspects of the fish digestive physiology that may affect the growth, we examined, firstly, variations in growth performance, feed intake, digestive enzyme activities, expression of transport related genes, metabolites in plasma and liver, and oxidative stress response in juveniles of greater amberjack (Seriola dumerili) growing during two months at 18, 22 and 26 degrees C of water temperature. Secondly, we analysed the epithelial function of the intestinal mucosa by electrophysiological ex-vivo experiments. As expected, body growth increased with increasing temperature in the tested range. Highest relative feed intake was observed at 26 degrees C, but the food conversion ratio was the same at 22 and 26 degrees C and less favourable at 18 degrees C. Digestive proteases activities were similar at 22 and 26 degrees C, while an evident effect of temperature was observed on lipids digestive capacity, being lipase activity undetectable at 18 degrees C. Electrophysiological assays revealed a relationship between temperature and intestinal mucosa plasticity. Temperature increase promoted epithelial functionality through higher tissue resistance and short-circuit current in mid-intestine at 26 degrees C, as well as better electrogenic amino acids transport. On the other hand, mRNA expression of peptide transporters tended to be higher in fish that grew at 18 degrees C, probably to reinforce the transport capacity. Plasma circulating levels of metabolites demonstrated higher energy and protein mobilization with the increasing temperature, where a hypometabolic state was denoted by lower cortisol levels at 18 degrees C together with an apparent switch from lipids to carbohydrate usage as energy source and increased oxidative stress in the liver at the lowest temperature. Altogether indicates that the tested temperatures are within the tolerance range for the species, although 22 and 26 degrees C appear as optimal temperatures for on-growing greater amberjack juveniles. Changes in nutrient digestion and absorption induced by temperature are related with both hydrolytic activity and remodelling of the intestinal mucosa. Impairing growth capacity and initial evidences of welfare compromise were observed at 18 degrees C.
- Anomaly detection in all-sky images: An approach using robust ensemble modeling of cloud cover fraction and prediction boundsPublication . Rocha, Vinicius Roggério da; Fisch, Gilberto; Costa, Rodrigo Santos; Ruano, AntonioAll-sky images (ASI) are widely used for sky monitoring, particularly in solar energy generation applications. Alignment issues and interferences demand a detection process of problematic images. With high sampling frequencies (1-2 images per minute), automating this process is crucial for managing large datasets and enabling integration into automatic systems, which is the objective of this work. For this purpose, a robust ensemble model, using the ApproxHull and Radial Basis Function (RBF) neural networks combined with Multi Objective Genetic Algorithms (MOGA) tools, was developed to compute the cloud cover fraction of each image. By computing the deviation between this result and the one obtained by the equipment, and by assessing if it lies within prediction bounds obtained in the design phase, an automatic method for detecting anomalies in All-sky images was obtained. ASI data collected during the Green Ocean (GoAmazon) Experiment 2014/5 was employed. The proposed approach obtained a Probability of Interval Coverage (PICP) similar to the user- specified level of confidence for several sets within what was classified as a "good"dataset, while being able to detect anomalies found within a "bad"dataset.
- Comparative study of Ruditapes philippinarum and Ruditapes decussatus in Ria de Aveiro, Portugal: Invasive species management and marine resource conservationPublication . Manuel da Silva Rodrigues Maia, Francisco; Gaspar, Miguel; Barroso, Carlos M.Research on the biological traits of commercial bivalves is essential for developing effective management strategies and ensuring their sustainable exploitation. This study offers a comparative analysis of the invasive Manila clam R. philippinarum and the native grooved carpet clam R. decussatus in the Ria de Aveiro, Portugal, focusing on shell morphometry, growth, reproductive cycle, condition index, and length at 50% maturity (L50). Analysis of internal shell microgrowth bands revealed that R. philippinarum exhibits a higher growth coefficient (K) than R. decussatus, with von Bertalanffy growth equations of Lt = 59.49 [1 - e -0.78 (t-0.55)1 and Lt = 75.09 [1 - e -0.33 (t0.10)1, respectively. Notably, the K value for R. philippinarum is among the highest recorded for this species, indicating exceptional growth performance in the Ria de Aveiro. The reproductive cycle analysis showed that R. philippinarum has a longer and more intense spawning period, extending from April to October 2013 and from April to September 2014, with peaks in August and September. In contrast, R. decussatus exhibited a shorter spawning season, from May to October 2013 and from June to September 2014, peaking in August. Seasonal variations in the condition index, likely linked to food availability and reproductive cycle, showed R. philippinarum in better condition during the early stages of gonadal development, indicating more efficient energy allocation towards reproduction. Rapid growth and fast sexual maturity during the first year of benthic life enable recruits of both species to spawn during the following year's spawning season. R. philippinarum reaches sexual maturity slightly faster than R. decussatus (L50 = 20.0 mm SL vs. L50 = 22.1 mm SL), maturing at around 1.08 years compared to 1.15 years. Although this difference is minor, it enables R. philippinarum recruits to begin reproduction approximately one month earlier in the year. Improved growth rates of R. philippinarum during its second and third years likely enhance reproductive capacity, as larger individuals typically produce more offspring. These results suggest that R. philippinarum has a competitive advantage over R. decussatus due to its faster growth and greater reproductive potential. However, these factors do not conclusively explain the rapid proliferation and establishment of R. philippinarum in the Ria de Aveiro, nor the sudden decline in R. decussatus populations following the introduction of the invasive species. Fishery management strategies are proposed based on two distinct scenarios.
- Dual-compartment-gate organic transistors for monitoring biogenic amines from foodPublication . Sergi, Ilenia; Sensi, Matteo; Zanotti, Rian; Tsironi, Theofania; Flemetakis, Emmanouil; Power, Deborah Mary; Bortolotti, Carlo Augusto; Biscarini, FabioAccording to the Food and Agriculture Organization of the United Nations (FAO) more than 14% of the world's food production is lost every year before reaching retail, and another 17% is lost during the retail stage. The use of the expiration date as the main estimator of the life-end of food products creates unjustified food waste. Sensors capable of quantifying the effective food freshness and quality could substantially reduce food waste and enable more effective management of food chain. We propose an electrolyte-gated organic transistor (EGOT) that responds to the release of biogenic amines, like diamines and tyramine, generated by degradation of protein-rich food. The EGOT sensor features a polymeric poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) gate electrode fabricated in the shape of a miniaturized beaker containing an aqueous solution in the inner side (to be exposed to food) and capacitively coupled through a hydrogel to the transistor channel on the outside (not in contact with food). The hydrogen bonds formed by the water-dissolved amines with PEDOT:PSS modulate the EGOT channel across a wide range of amine concentrations. We demonstrate that our sensor can detect different amines by the combinatorial analysis of the response from different channel materials, PEDOT:PSS and the other DPP-DTT, with a limit of detection as low as 100 pM.