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1.
Ann Glob Health ; 90(1): 41, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005643

RESUMO

A healthy ocean is essential for human health, and yet the links between the ocean and human health are often overlooked. By providing new medicines, technologies, energy, foods, recreation, and inspiration, the ocean has the potential to enhance human health and wellbeing. However, climate change, pollution, biodiversity loss, and inequity threaten both ocean and human health. Sustainable realisation of the ocean's health benefits will require overcoming these challenges through equitable partnerships, enforcement of laws and treaties, robust monitoring, and use of metrics that assess both the ocean's natural capital and human wellbeing. Achieving this will require an explicit focus on human rights, equity, sustainability, and social justice. In addition to highlighting the potential unique role of the healthcare sector, we offer science-based recommendations to protect both ocean health and human health, and we highlight the unique potential of the healthcare sector tolead this effort.


Assuntos
Mudança Climática , Oceanos e Mares , Humanos , Biodiversidade , Conservação dos Recursos Naturais , Setor de Assistência à Saúde , Direitos Humanos , Justiça Social , Desenvolvimento Sustentável
2.
Microbiome ; 12(1): 126, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010229

RESUMO

BACKGROUND: Single amplified genomes (SAGs) and metagenome-assembled genomes (MAGs) are the predominant sources of information about the coding potential of uncultured microbial lineages, but their strengths and limitations remain poorly understood. Here, we performed a direct comparison of two previously published collections of thousands of SAGs and MAGs obtained from the same, global environment. RESULTS: We found that SAGs were less prone to chimerism and more accurately reflected the relative abundance and the pangenome content of microbial lineages inhabiting the epipelagic of the tropical and subtropical ocean, as compared to MAGs. SAGs were also better suited to link genome information with taxa discovered through 16S rRNA amplicon analyses. Meanwhile, MAGs had the advantage of more readily recovering genomes of rare lineages. CONCLUSIONS: Our analyses revealed the relative strengths and weaknesses of the two most commonly used genome recovery approaches in environmental microbiology. These considerations, as well as the need for better tools for genome quality assessment, should be taken into account when designing studies and interpreting data that involve SAGs or MAGs. Video Abstract.


Assuntos
Bactérias , Metagenoma , Plâncton , RNA Ribossômico 16S , RNA Ribossômico 16S/genética , Bactérias/genética , Bactérias/classificação , Plâncton/genética , Plâncton/classificação , Plâncton/microbiologia , Filogenia , Água do Mar/microbiologia , Quimerismo , Genoma Bacteriano , Metagenômica/métodos , Microbiota/genética , Genômica
3.
Indian J Microbiol ; 64(2): 593-602, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39011007

RESUMO

Seaweed, a valuable marine resource widely cultivated worldwide, can be vulnerable to stress and microbiome alterations, resulting in the decay of seaweeds and substantial economic losses. To investigate the seaweed-microbiome interaction, our study aimed to isolate marine bacteria and fungi that can cause Ice-Ice disease and evaluate their enzymatic characteristics for potential application in bioethanol production from seaweed biomass. Three red seaweed species (Gracilaria edulis, Kappaphycus alvarezii, and Eucheuma cottonii) were obtained for our study and placed in separate culture tanks. Among the 18 isolated marine microbial species, 12 tested positive for agar and carrageenan activity: six exhibited both activities, three displayed only agar activity, and three only carrageenan activity. DNA sequencing of the positive microbes identified ten bacteria and two yeast species. The 3,5-Dinitrosalicylic acid (DNSA) assay results revealed that the identified bacterial Caldibacillus kokeshiiformis strain FJAT-47861 exhibited the highest carrageenase activity (0.76 units/ml), while the yeast Pichia fermentans strain PM79 demonstrated the highest agarase activity (0.52 units/ml). Notably, Pichia fermentans strain PM79 exhibited the highest overall agarase and carrageenase activity, averaging 0.63 units/ml. The average carrageenase activity of all six positive microbes was 1.5 times higher than their agarase activity. These findings suggest that the 12 isolated microbes hold potential for bioethanol production from macroalgae, as their agarase and carrageenase activity indicates their ability to break down seaweed cell wall carbohydrates, causing ice-ice disease. Moreover, these results provide exciting prospects for harnessing the bioconversion capabilities of these microbes, paving the way for sustainable and efficient bioethanol production from seaweed resources. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01205-w.

5.
J Basic Microbiol ; : e2400210, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014937

RESUMO

Research on fungal volatile organic compounds (VOCs) has increased worldwide in the last 10 years, but marine fungal volatilomes remain underexplored. Similarly, the hormone-signaling pathways, agronomic significance, and biocontrol potential of VOCs in plant-associated fungi make the area of research extremely promising. In the current investigation, VOCs of the isolates-Aspergillus sp. GSBT S13 and GSBT S14 from marine sediments, and Bulbithecium sp. GSBT E3 from Eucalyptus foliage were extracted using Head Space solid phase microextraction, followed by gas chromatography-mass spectrometry, identification, statistical analyses, and prediction of functions by KEGG COMPOUND and STITCH 5.0 databases. The significance of this research is fingerprinting VOCs of the isolates from distinct origins, identification of compounds using three libraries (NIST02, NIST14, and W9N11), and using bioinformatic tools to perform functional analysis. The most important findings include the identification of previously unreported compounds in fungi-1-methoxy naphthalene, diethyl phthalate, pentadecane, pristane, and nonanal; the prediction of the involvement of small molecules in the degradation of aromatic compound pathways and activation, inhibition, binding, and catalysis of metabolites with predicted protein partners. This study has ample opportunity to validate the findings and understand the mechanism or mode of action, the interspecies interactions, and the role of the metabolites in geochemical cycles.

6.
Genome Biol Evol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018026

RESUMO

The viviparous eelpout Zoarces viviparus is a common fish across the North-East Atlantic and has successfully colonized habitats across environmental gradients. Due to its wide distribution and predictable phenotypic responses to pollution, Z. viviparus is used as bioindicator organism and has been routinely sampled over decades by several countries to monitor marine environmental health. Additionally, this species is a promising model to study adaptive processes related to environmental change, specifically global warming. Here, we report the chromosome-level genome assembly of Z. viviparus, which has a size of 663 mega base pairs (mbp) and consists of 607 scaffolds (N50 = 26 mbp). The 24 largest represent the 24 chromosomes of the haploid Z. viviparus genome, which harbors 98% of the complete BUSCOs defined for ray-finned fish, indicating that the assembly is highly contiguous and complete. Comparative analyses between the Z. viviparus assembly and chromosome-level genomes of two other eelpout species revealed a high synteny, but also an accumulation of repetitive elements in the Z. viviparus genome. Our reference genome will be an important resource enabling future in-depth genomic analyses of the effects of environmental change in this important bioindicator species.

7.
Environ Pollut ; : 124501, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39025293

RESUMO

Marine biofouling is considered one of the major biophysical processes influencing the vertical dynamics of plastic debris in seawater. We numerically implement, for the first time, this mechanism within a fine-resolution, regional model of the Tyrrhenian Sea, in order to simulate the dispersion of microplastics (MPs) released at the mouth of a highly polluting river. Four polymers and three particle sizes are used to quantify algal concentration influence on the trajectories, fates, and accumulation spots of the tracked MPs, by comparing 2002 winter and summer runs encompassing or not biofouling. Besides a marked seasonality for most of the MP types and radii tested, biofouling effects are prominently observed for only 2 polymers and particles bigger than 1µm. Thus, further realistic applications of the biofouling mechanism in oceanic circulation models are required to achieve a thorough assessment of its impact on plastic density within distinctive basins of the world seas.

8.
UCL Open Environ ; 6: e1970, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015301

RESUMO

Global challenges such as climate change, food security and human health and well-being disproportionately impact people from low-income countries. These challenges are complex and require an international and transdisciplinary approach to research, with research skills and expertise from different disciplines, sectors and regions. In addressing this, a key goal of the research project, Blue Communities, was to create and expand mutual interdisciplinary capacity of both United Kingdom and Southeast Asian Partners. An existing questionnaire on research capacity was uniquely adapted to include interdisciplinary and international aspects and distributed for the first time as an online survey to the participants of the Blue Communities project comprising researchers across all career stages. Participants were asked about their perceptions of the research capacity and culture of their organisation, team and self and whether they believed any aspects have changed since their involvement with the project. Greatest improvement was seen at the self-level where results indicated a positive relationship between an individual's current success or skill and their improvement over the course of the research project across 18 out of 22 aspects of research capacity for Southeast Asian, and two for UK respondents. The conflict between achieving research aims, building research capacity and making societal impact was evident. Institutional support is required to value these core aspects of interdisciplinary research.

9.
Mol Microbiol ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970428

RESUMO

Microscale interactions between marine phytoplankton and bacteria shape the microenvironment of individual cells, impacting their physiology and ultimately influencing global-scale biogeochemical processes like carbon and nutrient cycling. In dilute environments such as the ocean water column, metabolic exchange between microorganisms likely requires close proximity between partners. However, the biological strategies to achieve this physical proximity remain an understudied aspect of phytoplankton-bacterial associations. Understanding the mechanisms by which these microorganisms establish and sustain spatial relationships and the extent to which spatial proximity is necessary for interactions to occur, is critical to learning how spatial associations influence the ecology of phytoplankton and bacterial communities. Here, we provide an overview of current knowledge on the role of space in shaping interactions among ocean microorganisms, encompassing behavioural and metabolic evidence. We propose that characterising phytoplankton-bacterial interactions from a spatial perspective can contribute to a mechanistic understanding of the establishment and maintenance of these associations and, consequently, an enhanced ability to predict the impact of microscale processes on ecosystem-wide phenomena.

10.
Meat Sci ; 216: 109584, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38970931

RESUMO

The addition of macroalgae to livestock diets has demonstrated to enhance the quality of meat by improving the muscle stability, antioxidant capacity and fatty acid profile. However, information regarding rabbit meat is scarce. This study evaluated the effect of adding 1.025% of different macroalgae, dehydrated and as extracts (Saccharina latissima, Himanthalia elongata and Ulva spp.) to the diet of growing rabbits. Dietary supplementation with the Ulva spp. extract increased the fat content (0.96% vs 0.33% in control group) and the proportion of monounsaturated fatty acids (by 22%; P ≤ 0.022), but did not affect the moisture, protein or ash contents or the physicochemical properties of the rabbit longissiumus lumborum muscle. The antioxidant status of the meat was adequate and was not affected by the dietary supplements. The sensorial properties of the meat were also not affected, and dietary supplementation with both S. latissima and H. elongata actually enhanced the flavour and juiciness of the meat (P ≤ 0.01). Altogether, the study findings indicate that the addition of these sustainable ingredients to rabbit feed did not negatively affect meat quality, and some of them may potentially improve specific characteristics, which could make this meat more attractive to consumers.

11.
Eur J Med Chem ; 276: 116644, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38971051

RESUMO

Ion channels are a type of protein channel that play a vital role in numerous physiological functions by facilitating the passage of ions through cell membranes, thereby enabling ion and electrical signal transmission. As a crucial target for drug action, ion channels have been implicated in various diseases. Many natural products from marine organisms, such as fungi, algae, sponges, and sea cucumber, etc. have been found to have activities related to ion channels for decades. These interesting natural product molecules undoubtedly bring good news for the treatment of neurological and cardiovascular diseases. In this review, 92 marine natural products and their synthetic derivatives with ion channel-related activities that were identified during the period 2000-2024 were systematically reviewed. The synthesis and mechanisms of action of selected compounds were also discussed, aiming to offer insights for the development of drugs targeting ion channels.

12.
Conserv Biol ; : e14327, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989837

RESUMO

Growing human use of the marine environment increases the proximity of humans to marine wildlife and thus likely increases human-wildlife interactions. Such interactions influence perceptions of nature and promote or undermine conservation. Despite their importance, human-wildlife interactions are rarely considered in ecosystem-based marine spatial planning (MSP). Ideally, these interactions should be identified and considered in ecosystem-based management (EBM), which is often purported to be the basis for MSP. We used Marxan software and data from a citizen science project documenting location, species, age, sex, and activity type to identify regions along Israel's coast with a high probability of encounters between people and 2 species of guitarfish. We considered the geographic distribution of these encounters and the various activities undertaken by the reporting observers. We ran 4 scenarios in Marxan. Two had conservation goals of 30% and 50% guitarfish habitat protection. In the third and fourth scenarios, we added a 50% conservation goal of human leisure activities to each guitarfish conservation goal. We also conducted a gap analysis between our guitarfish conservation goals and the Israel Nature and Parks Authority's master plan for marine protected areas. We found the park authority was close to meeting the 30% goal but was far from meeting the conservation goal of 50% of guitarfish habitat conservation. Different human uses were more likely to interact with different life stages of guitarfish, and different recreational activities occurred in different areas. Identifying areas of specific human use showed which activities should be addressed in conservation management decisions. Our addition of certain recreational uses to the model of habitat conservation showed how enhancing human dimensions in conservation planning can lead to more holistic ecosystem-based conservation necessary for effective marine planning.


Incorporación de las interacciones humano­fauna dentro de la gestión basada en el ecosistema para mejorar la conservación del pez guitarra en peligro Resumen El uso creciente que el humano le da al mar incrementa la cercanía de las personas con la fauna marina, lo que probablemente incrementa las interacciones humano­fauna. Dichas interacciones influyen sobre las percepciones que se tienen de la naturaleza y promueven debilitan la conservación. A pesar de su importancia, pocas veces se consideran las relaciones humano­fauna dentro de la planeación espacial basada en ecosistemas marinos (PEM). Lo ideal debería ser la identificación y consideración de estas interacciones dentro de la gestión basada en el ecosistema (GBE), la cual con frecuencia se considera como la base de la PEM. Usamos software Marxan y datos de un proyecto de ciencia ciudadana que documenta la ubicación, especie, edad, sexo y tipo de actividad para identificar las regiones de la costa de Israel con una alta probabilidad de encuentros entre las personas y dos especies de pez guitarra. Consideramos la distribución geográfica de estos encuentros y las diferentes actividades que realizan los observadores. En Marxan corrimos cuatro escenarios. Dos de los escenarios contaban objetivos de conservación del 30% y 50% de la protección del hábitat del pez guitarra. En los otros dos escenarios, añadimos un objetivo de conservación de 50% de las actividades humanas de recreación a los objetivos uno y dos. También realizamos un análisis de brecha entre los objetivos de conservación del pez guitarra y el plan maestro para las áreas marinas protegidas de la Autoridad de Parques y Naturaleza de Israel. Descubrimos que esta autoridad estaba cerca de lograr el objetivo del 30% pero lejos del de 50% de la conservación del hábitat del pez guitarra. Fue más probable que los diferentes usos humanos interactuaran con diferentes estadios de vida del pez guitarra y las diversas actividades recreativas ocurrieron en áreas distintas. La identificación de las áreas con un uso humano específico mostró cuáles actividades deberían abordarse en las decisiones de gestión de la conservación. La suma de ciertos usos recreativos al modelo de conservación del hábitat mostró cómo aumentar las dimensiones humanas en la planeación de la conservación puede derivar en una conservación basada en el ecosistema más holística, necesaria para la planeación marina eficiente.

13.
Phytother Res ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990182

RESUMO

The incidences of endocrine and metabolic disorders like diabetes have increased worldwide. Several proposed molecular pathways mechanisms for the management of diabetes have been identified, but glycaemic control is still a challenging task in the drug discovery process. Most of the drug discovery processes lead to numerous scaffolds that are prominent in natural products. The review deals with the natural bioactives as an α-amylase inhibitors, α-glucosidase inhibitors, protein tyrosine phosphatase-1B inhibitors, dipeptidyl peptidase-IV inhibitors, G-protein coupled receptors-40 agonists, PPAR-γ agonists and the activators of 5'-adenosine monophosphate-activated protein kinase and glucokinase. So, in this review, we focused on the hypoglycaemic bioactives, which will assist scientific developers, traditional medicinal practitioners, and readers to discover some potent antidiabetic molecules. Strategies like chemometric approaches, scaffold hopping, and total synthesis of natural products by group modification or ring opening/closing mechanism could be useful for the development of novel hit/lead antidiabetic molecules. The study concludes that each phyto molecule inherits a potential to get explored by repurposing techniques for various antidiabetic targets and offer an alternative antidiabetic therapeutic medicinal potential.

14.
Aquat Toxicol ; 273: 107016, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38991362

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) accumulate and integrate into aquatic environments, raising concerns about the well-being and safety of aquatic ecosystems. Benzo[a]pyrene (BaP), a persistent PAH commonly detected in the environment, has been extensively studied. However, the broader multifaceted toxicity potential of BaP on the early life stages of marine fish during chronic exposure to environmentally relevant concentrations needs further exploration. To fill these knowledge gaps, this study assessed the in vivo biotoxicity of BaP (1, 4, and 8 µg/L) in marine medaka (Oryzias melastigma) during early development over a 30-day exposure period. The investigation included morphological, biochemical, and molecular-level analyses to capture the broader potential of BaP toxicity. Morphological analyses showed that exposure to BaP resulted in skeletal curvatures, heart anomalies, growth retardation, elevated mortality, delayed and reduced hatching rates. Biochemical analyses revealed that BaP exposure not only created oxidative stress but also disrupted the activities of antioxidant enzymes. This disturbance in redox balance was further explored by molecular level investigation. The transcriptional profiles revealed impaired oxidative phosphorylation (OXPHOS) and tricarboxylic acid (TCA) cycle pathways, which potentially inhibited the oxidative respiratory chain in fish following exposure to BaP, and reduced the production of adenosine triphosphate (ATP) and succinate dehydrogenase (SDH). Furthermore, this investigation indicated a potential connection to apoptosis, as demonstrated by fluorescence microscopy and histological analyses, and supported by an increase in the expression levels of related genes via real-time quantitative PCR. This study enhances our understanding of the molecular-level impacts of BaP's multifaceted toxicity in the early life stages of marine medaka, and the associated risks.

15.
Sci Total Environ ; 947: 174661, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992372

RESUMO

The standard techniques for monitoring beach litter focus on the litter that is accumulated on beaches. Therefore, the underwater bathing area is usually overlooked. Our study aims to start the discussion about the litter in the bathing area, an important connection between the exposed beach and the ocean. We aimed to compare sampling methodologies between the underwater bathing area and the exposed beach. We highlighted litter's similarities and differences regarding the amount, material, possible sources, and interaction with the biota. We also performed a brand audit on the underwater bathing area litter. In the underwater region, 106 items were collected while 1706 items were collected from the exposed beach region. Plastic was the dominant type of material in both sites, exposed beach (89.92 %) and bathing area (83.96 %). The litter's possible source was different. In the underwater bathing area was more related to food packages (couscous, rice). On the other hand, litter on the exposed beach was associated with beach use (single-use plastic such as plastic cups). The brand audit identified 21 companies, whereby most brands were Brazilian and food-related. Regarding interactions with the biota, the litter in the bathing area had more bio-fouling (87.73 %) than the litter collected on the exposed beach (10.00 %). Information about bathing area litter can be useful to draw different management strategies. Due to the differences in litter types and behavior between the two sites, the same mitigation strategies might not be equally efficient.

16.
Sci Total Environ ; 946: 174403, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38960198

RESUMO

Conventional plastics have become a major environmental concern due to their persistence and accumulation in marine ecosystems. The development of potential degradable polymers (PBP), such as polyhydroxyalkanoates (PHAs) and polylactic acid (PLA), has gained attention as an alternative to mitigate plastic pollution, since they have the potential to biodegrade under certain conditions, and their production is increasing as replacement of conventional polyolefins. This study aimed to assess and compare the toxicity of leachates of pre-compounding PBP (PLA and the PHA, polyhydroxybutyrate-covalerate (PHBv)) and polypropylene (PP) on five marine planktonic species. A battery of standard bioassays using bacteria, microalgae, sea urchin embryos, mussel embryos and copepod nauplii was conducted to assess the toxicity of leachates from those polymers. Additionally, the presence of chemical additives in the leachates was also verified through GC-MS and LC-HRMS analysis. Results showed that PHBv leachates exhibited higher toxicity compared to other polymers, with the microalgae Rhodomonas salina, being the most sensitive species to the tested leachates. On the other hand, PP and PLA generally displayed minimal to no toxicity in the studied species. Estimated species sensitivity distribution curves (SSD) show that PHBv leachates can be 10 times more hazardous to marine plankton than PP or PLA leachates, as demonstrated by the calculated Hazardous Concentration for 5 % of species (HC5). Qualitative chemical analysis supports the toxicological results, with 80 % of compounds being identified in PHBv leachates of which 2,4,6-trichlorophenol is worth mentioning due to the deleterious effects to aquatic biota described in literature. These findings underscore the fact that whereas environmental persistence can be targeted using PBP, the issue of chemical safety remains unsolved by some alternatives, such as PHBv. Gaining a comprehensive understanding of the toxicity profiles of PBP materials through a priori toxicological risk assessment is vital for their responsible application as alternatives to conventional plastics.

17.
Proc Natl Acad Sci U S A ; 121(29): e2400592121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38980905

RESUMO

The expansion of marine protected areas (MPAs) is a core focus of global conservation efforts, with the "30x30" initiative to protect 30% of the ocean by 2030 serving as a prominent example of this trend. We consider a series of proposed MPA network expansions of various sizes, and we forecast the impact this increase in protection would have on global patterns of fishing effort. We do so by building a predictive machine learning model trained on a global dataset of satellite-based fishing vessel monitoring data, current MPA locations, and spatiotemporal environmental, geographic, political, and economic features. We then use this model to predict future fishing effort under various MPA expansion scenarios compared to a business-as-usual counterfactual scenario that includes no new MPAs. The difference between these scenarios represents the predicted change in fishing effort associated with MPA expansion. We find that regardless of the MPA network objectives or size, fishing effort would decrease inside the MPAs, though by much less than 100%. Moreover, we find that the reduction in fishing effort inside MPAs does not simply redistribute outside-rather, fishing effort outside MPAs would also decline. The overall magnitude of the predicted decrease in global fishing effort principally depends on where networks are placed in relation to existing fishing effort. MPA expansion will lead to a global redistribution of fishing effort that should be accounted for in network design, implementation, and impact evaluation.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Oceanos e Mares , Ecossistema , Aprendizado de Máquina , Peixes
18.
Heliyon ; 10(12): e32515, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38994086

RESUMO

Ocean currents are emerging as key contributors to renewable energy generation. However, technologies for harvesting tidal current energy are still in the early stages of development. In this context, environmental and economic studies on tidal energy converters (TECs) are crucial to further advance tidal technology and facilitate its entry into the market. This article presents a life cycle and economic assessment of a 34.5 MW tidal farm project comprising 23 second-generation tidal devices, each with a rated power of 1.5 MW. The tidal system was simulated using primary data from the full-scale floating platform Atir. The Atir is a pre-commercial tidal device designed with a steel trimaran and a submerged section for TEC installation. An assessment of 18 environmental impact categories was conducted using the ReCiPe 2016 MidPoint method, with process flow systems modelled using SimaPro v9.2.0.1 software. The environmental assessment indicates emissions of 42.11 g CO2eq per kWh, primarily stemming from manufacturing processes that demand substantial amounts of steel. The economic analysis reveals a Levelized Cost of Electricity (LCOE) of 0.125 EUR/kWh, consistent with European Commission projections. Although the platform structure represents a high initial investment, the lower maintenance costs of the Atir device provide long-term savings and, overall, result in a competitive LCOE. The study also introduces a methodological framework for harmonised environmental and economic assessments in tidal energy projects, proving crucial in supporting decision-making processes.

19.
Biochem Biophys Res Commun ; 729: 150357, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39002194

RESUMO

ß-N-acetylglucosaminidase (GlcNAcase) is an essential biocatalyst in chitin assimilation by marine Vibrio species, which rely on chitin as their main carbon source. Structure-based phylogenetic analysis of the GlcNAcase superfamily revealed that a GlcNAcase from Vibrio campbellii, formerly named V. harveyi, (VhGlcNAcase) belongs to a major clade, Clade A-I, of the phylogenetic tree. Pre-steady-state and steady-state kinetic analysis of the reaction catalysed by VhGlcNAcase with the fluorogenic substrate 4-methylumbelliferyl N-acetyl-ß-D-glucosaminide suggested the following mechanism: (1) the Michaelis-Menten complex is formed in a rapid enzyme-substrate equilibrium with a Kd of 99.1 ± 1 µM. (2) The glycosidic bond is cleaved by the action of the catalytic residue Glu438, followed by the rapid release of the aglycone product with a rate constant (k2) of 53.3 ± 1 s-1. (3) After the formation of an oxazolinium ion intermediate with the assistance of Asp437, the anomeric carbon of the transition state is attacked by a catalytic water, followed by release of the glycone product with a rate constant (k3) of 14.6 s-1, which is rate-limiting. The result clearly indicated a three-step "ping-pong" mechanism for VhGlcNAcase.

20.
Mar Pollut Bull ; 206: 116685, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39002220

RESUMO

Human activities emitting carbon dioxide (CO2) have caused severe greenhouse effects and accelerated climate change, making carbon neutrality urgent. Seawater mineral carbonation technology offers a promising negative emission strategy. This work investigates current advancements in proposed seawater mineral carbonation technologies, including CO2 storage and ocean chemical carbon sequestration. CO2 storage technology relies on indirect mineral carbonation to fix CO2, involving CO2 dissolution, Ca/Mg extraction, and carbonate precipitation, optimized by adding alkaline substances or using electrochemical methods. Ocean chemical carbon sequestration uses natural seawater for direct mineral carbonation, enhanced by adding specific materials to promote carbonate precipitation and increase CO2 absorption, thus enhancing marine carbon sinks. This study evaluates these technologies' advantages and challenges, including reaction rates, costs, and ecological impacts, and analyzes representative materials' carbon fixation potential. Literature indicates that seawater mineral carbonation can play a significant role in CO2 storage and enhancing marine carbon sinks in the coming decades.

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