Search

Iron is an essential nutrient for all microorganisms of the marine environment. Iron limitation of primary production has been well documented across a significant portion of the global surface ocean, but much less is known regarding the potential for iron limitation of the marine heterotrophic microbial community. In this work, we characterize the transcriptomic response of the heterotrophic bacterial community to iron additions in the California Current System, an eastern boundary upwelling system, to detect in situ iron stress of heterotrophic bacteria. Changes in gene expression in response to iron availability by heterotrophic bacteria were detected under conditions of high productivity when carbon limitation was relieved but when iron availability remained low. The ratio of particulate organic carbon to dissolved iron emerged as a biogeochemical proxy for iron limitation of heterotrophic bacteria in this system. Iron stress was characterized by high expression levels of iron transport pathways and decreased expression of iron-containing enzymes involved in carbon metabolism, where a majority of the heterotrophic bacterial iron requirement resides. Expression of iron stress biomarkers, as identified in the iron-addition experiments, was also detected insitu. These results suggest iron availability will impact the processing of organic matter by heterotrophic bacteria with potential consequences for the marine biological carbon pump.

Polymorphic yeasts can switch between unicellular division and multicellular filamentous growth. Although prevalent in aquatic ecosystems, such as the open ocean, we have a limited understanding of the controlling factors on their morphological variation in an aquatic ecology context. Here we show that substrate concentration regulates cell morphogenesis in a cosmopolitan polymorphic yeast, Aureobasidium pullulans, isolated from the pelagic open ocean and analyzed in liquid batch culture. Filamentous cell development was triggered only under high initial substrate conditions, suggesting that hyphal growth could be more advantageous under eutrophic conditions and may influence pelagic fungal interactions with particulate organic matter. Filamentous growth proportionally declined before the exhaustion of substrate and before budding yeast-type cell division entered stationary phase, possibly modulated by quorum sensing as previously evidenced in other polymorphic yeasts. We also found that budding yeast-type unicells decreased in size and became more elongated in shape in response to substrate depletion, resulting in higher cell surface area to volume ratios, which could affect yeast dispersal and/or provide a nutrient uptake advantage under oligotrophic conditions. Our results demonstrate resource-responsive morphological plasticity in a marine-derived polymorphic yeast, providing mechanistic insight into the ability of fungi to survive fluctuating environmental conditions such as in the open ocean. [ABSTRACT FROM AUTHOR]

A metagenomic time series from Arctic seawater was obtained from Dease Strait, to analyse the changes in bacterioplankton caused by the summer phytoplankton bloom. Bacterial clades specialized in the metabolism of polysaccharides, such as Bacteroidetes, became dominant along the bloom. These specialized taxa quickly displaced the microbial clades that dominate nutrient-poor waters during early spring, such as Archaea, Alpha-and Gammaproteobacteria. At the functional level, phyla Bacteroidetes, Planctomycetes, and Verrucomicrobia showed higher contents of polysaccharide-degradation functions. The Bacteroidetes community shifted toward species with higher polysaccharide-degrading capabilities, targeting algal polysaccharides in summer. Regarding transporters, Bacteroidetes dominated SusC-TonB transporters and had an exclusive family of glycoside-binding proteins (SusD). These proteins were used to identify polysaccharide-utilization loci that clustered transporters and polysaccharide-active enzymes, showing a higher level of specialization toward polysaccharide use. Altogether, these genomic features point to the genetic adaptations that promote the dominance of Bacteroidetes during phytoplankton blooms. [ABSTRACT FROM AUTHOR]

Environmental transitions, such as the salinity divide separating marine and fresh waters, shape biodiversity over both shallow and deep timescales, opening up new niches and creating opportunities for accelerated speciation and adaptive radiation. Understanding the genetics of environmental adaptation is central to understanding how organisms colonise and subsequently diversify in new habitats. We used time‐resolved transcriptomics to contrast the hyposalinity stress responses of two diatoms. Skeletonema marinoi has deep marine ancestry but has recently invaded brackish waters. Cyclotella cryptica has deep freshwater ancestry and can withstand a much broader salinity range. Skeletonema marinoi is less adept at mitigating even mild salinity stress compared to Cyclotella cryptica, which has distinct mechanisms for rapid mitigation of hyposaline stress and long‐term growth in low salinity. We show that the cellular mechanisms underlying low salinity tolerance, which has allowed diversification across freshwater habitats worldwide, includes elements that are both conserved and variable across the diatom lineage. The balance between ancestral and lineage‐specific environmental responses in phytoplankton have shaped marine–freshwater transitions on evolutionary timescales and, on contemporary timescales, will affect which lineages survive and adapt to changing ocean conditions. [ABSTRACT FROM AUTHOR]

Globally, ocean dumping of chemical waste is a common method of disposal and relies on the assumption that dilution, diffusion, and dispersion at ocean scales will mitigate human exposure and ecosystem impacts. In southern California, extensive dumping of agrochemical waste, particularly chlorinated hydrocarbon contaminants such as DDT, via sewage outfalls and permitted offshore barging occurred for most of the last century. This study compiled a database of existing sediment and fish DDT measurements to examine how this unique legacy of regional ocean disposal translates into the contemporary contamination of the coastal ocean. We used spatiotemporal modeling to derive continuous estimates of sediment DDT contamination and show that the spatial signature of disposal (i.e., high loadings near historic dumping sites) is highly conserved in sediments. Moreover, we demonstrate that the proximity of fish to areas of high sediment loadings explained over half of the variation in fish DDT concentrations. The relationship between sediment and fish contamination was mediated by ecological predictors (e.g., species, trophic ecology, habitat use), and the relative influence of each predictor was context-dependent, with habitat exhibiting greater importance in heavily contaminated areas. Thus, despite more than half a century since the cessation of industrial dumping in the region, local ecosystem contamination continues to mirror the spatial legacy of dumping, suggesting that sediment can serve as a robust predictor of fish contamination, and general ecological characteristics offer a predictive framework for unmeasured species or locations. [ABSTRACT FROM AUTHOR]

Within the framework of safeguarding Egypt’s coastal lowlands, which face escalating susceptibility to both climate change and human interventions, this study aims to provide a comprehensive analysis of sediment transport dynamics and their implications, with Damietta serving as a case study. To achieve this, a thorough review of the existing literature on sediment transport dynamics was conducted. MIKE21 Shoreline Morphology (MIKE21 SM) model was employed to simulate longshore sediment transport (LST) dynamics both before and after the construction of Damietta Port (DP). Analysis of the model output revealed that the model underestimated the infl uence of waves, primarily originating from the Northwest, on shaping the LST pattern. The results indicate that the construction of DP led to a reduction in average gross longshore sediment transport (GLST) and average net longshore sediment transport (NLST) by 18%, decreasing from 1.1 to 0.9 106 x m³ /year, and 42%, decreasing from 0.73 to 0.42 x 106 m3/year, respectively. Additionally, the average monthly GLST and NLST reductions were 17% and 37%, respectively, compared to pre-construction conditions. Consequently, this research underscores the importance of continuous monitoring of sediment transport to ensure shoreline stability and protect surrounding ecological systems. This recommendation is vital for managing and mitigating the impacts of ongoing and future coastal interventions. [ABSTRACT FROM AUTHOR]

Glass beads laid on the road, mainly used for better visibility, can contribute to harmful anthropogenic waste to the marine environment, and it is a prerequisite to distinguish the chemical properties associated with it. This is the first systematic approach and evaluation of the toxic and non-toxic characteristics of the glass beads from the Indian coastal region (Goa state), which originated from the wearing of road paint over a period. Glass beads ranging from a few hundred to ~ 1000 µm were found on various beaches far from the roadside throughout the coastal state. Examination of these glass beads revealed the possible contribution of toxic elements such as arsenic, lead, cadmium, chromium, and barium beyond the global regulatory limit. Mercury and other analyzed elements are within acceptable limits. However, a quantitative assessment of their environmental impact indicates that glass beads can impact the marine ecosystem and increase the background level of environmental pollutants. [ABSTRACT FROM AUTHOR]

Separating the scavenging process from the lubrication methodology in conventional two-stroke engines is an effective method of reducing emissions. Segregation of scavenging by use of stepped pistons is one such method providing significant improvements in engine durability, and reduced lubricant consumption, together with reduced production cost. The study discusses the approaches used together with those applied to conventional engines. This paper focusses on a marine outboard motor application and cross-comparisons with a comparable four-stroke outboard motor are drawn within the study. One-dimensional computational fluid dynamics models of the engine types have allowed performance and emissions simulations. Where possible, data from experimental dynamometer testing is compared with the theoretical models. A reasonable level of correlation in terms of performance has been observed. Two-stroke cycle engines are able to demonstrate reduced oxides of nitrogen emissions when compared with conventional four-stroke engines. Models of the stepped piston engine have confirmed the lower NOx emission evident with operation on the two-stroke cycle. [ABSTRACT FROM AUTHOR]

Xylose is an abundant, inexpensive and readily available carbohydrate common in minimally processed feedstocks such as seaweed and algae. While a wide variety of marine microbes have evolved to utilize seaweed and algae, only a few currently have the requisite characteristics and genetic engineering tools necessary to entertain the use of these underutilized feedstocks. The rapidly growing Gram‐negative halophilic bacterium Vibrio natriegens is one such chassis. In this study, we engineered and tested xylose induction in V. natriegens as a tool for scalable bioproduction applications. First, we created a sensing construct based on the xylose operon from Escherichia coli MG1665 and measured its activity using a fluorescent reporter and identified that cellular import plays a key role in induction strength and that expression required the XylR transcription factor. Next, we identified that select deletions of the promoter region enhance gene expression, limiting the effect of carbohydrate repression when xylose is used as an inducer in the presence of industrially relevant carbon sources. Lastly, we used the optimized constructs to produce the biopolymer melanin using seawater mimetic media. One of these formulations utilized a nori‐based seaweed extract as an inducer and demonstrated melanin yields comparable to previously optimized methods using a more traditional and costly inducer. Together, the results demonstrate that engineering xylose induction in V. natriegens can provide an effective and lower cost option for timed biosynthesis in scalable biomanufacturing applications using renewable feedstocks. [ABSTRACT FROM AUTHOR]

The editorial "Insights in aquatic microbiology: 2023" published in Frontiers in Microbiology explores the diverse interactions and dynamics of microorganisms in aquatic ecosystems. The research covers various environments, from oceans to lakes, rivers, and other water bodies, focusing on nutrient cycling, energy flow, and ecosystem health. The publication highlights recent findings in freshwater and saltwater ecosystems, emphasizing the importance of understanding microbial communities for environmental conservation and management. The editorial calls for the adoption of new technologies, interdisciplinary collaboration, and science-based policies to advance research in aquatic microbiology and promote sustainable ecosystem development. [Extracted from the article]

With the continual increase in global cheese consumption, rennet, the traditional milk coagulant, is unable to meet the growing demand in cheese production. Although several proteases from other sources have been used for cheese-making, they suffer various shortcomings. The ocean is home to a huge and diverse range of life forms, which represent a vast potential source of proteases. Marine proteases have been isolated from a number of marine species, including sponge, jellyfish, seaweed and marine animals, and some have been shown to be suitable as milk-clotting enzymes for cheese making. This review summarizes the latest studies on rennet substitutes from marine resources and their role in cheese-making. The emphasis of the review is on the isolation and purification of the marine proteases, the biochemical characteristics of these enzymes, especially their caseinolytic and milk-clotting properties, as well as their cleavage sites on casein. Some of the marine proteases have been applied as milk-clotting agent in cheese-making, with the resultant production of cheese with comparable characteristics, including sensory characteristics, to calf rennet cheese. The review concludes by highlighting the challenges and opportunities for future research in the field. [ABSTRACT FROM AUTHOR]

In an era when ecological and environmental needs and responsibilities apply pressure on the world's countries and sustainability takes centre stage, ecologic/environmental (E/E) laboratories stand as beacons of scientific inquiry, innovating, optimising, and applying various tests for a better knowledge of our natural resources and the quality status of ecosystems. The purpose of this review is to provide an overview of the use of flow cytometry (FC) as a tool for assessing environmental quality, mainly using living organisms and their biological changes as bioindicators. Cytometric approaches applied to both marine and terrestrial ecosystems ensure the detection of biochemical and functional status of the cells composing either an organ thereof or the organism itself. In addition to cytometric evaluations of the biotic matrix, a brief overview of the techniques for the environmental assessment of biotic and abiotic matrices using mass spectrometry is given. The technique involving the continuous monitoring of the chemical and physical parameters of water, sediment, and soil is basically incapable of detecting any additive and synergetic effects of toxicants on living organisms. Therefore, techniques employing bioindicators provide valuable information for environmental diagnosis, and several studies have demonstrated the strong relationship between specific environmental data and cell/organ behaviour. [ABSTRACT FROM AUTHOR]

Strain AA17T was isolated from an apparently healthy fragment of Montipora capitata coral from the reef surrounding Moku o Loʻe in Kāne'ohe Bay, O'ahu, Hawai'i, USA, and was taxonomically evaluated using a polyphasic approach. Comparison of a partial 16S rRNA gene sequence found that strain AA17T shared the greatest similarity with Aestuariibacter halophilus JC2043T (96.6%), and phylogenies based on 16S rRNA gene sequences grouped strain AA17T with members of the Aliiglaciecola, Aestuariibacter, Lacimicrobium, Marisediminitalea, Planctobacterium, and Saliniradius genera. To more precisely infer the taxonomy of strain AA17T, a phylogenomic analysis was conducted and indicated that strain AA17T formed a monophyletic clade with A. halophilus JC2043T, divergent from Aestuariibacter salexigens JC2042T and other related genera. As a result of monophyly and multiple genomic metrics of genus demarcation, strain AA17T and A. halophilus JC2043T comprise a distinct genus for which the name Fluctibacter gen. nov. is proposed. Based on a polyphasic characterisation and identifying differences in genomic and taxonomic data, strain AA17T represents a novel species, for which the name Fluctibacter corallii sp. nov. is proposed. The type strain is AA17T (= LMG 32603 T = NCTC 14664T). This work also supports the reclassification of A. halophilus as Fluctibacter halophilus comb. nov., which is the type species of the Fluctibacter genus. Genomic analyses also support the reclassification of Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica. [ABSTRACT FROM AUTHOR]

This manuscript documents the diagenetic progression from deposition to early burial of freshwater low‐Mg calcite mud within a Holocene sequence of the Everglades and Florida Bay (Florida, USA). During initial, in situ burial, the texturally‐complex, organic‐rich mud, exhibits high susceptibility to alteration, within a primarily dissolution‐driven realm. Seaward, a brackish‐water transitional burial environment currently displays evidence of mixed precipitation and dissolution. This brackish stage burial alteration may be due to fluid exchange (a relatively high fluid‐to‐rock ratio) in a submerged estuary setting. Lastly, the burial environment in Florida Bay records a transgression from freshwater to near‐normal marine conditions. This island setting currently exhibits a diagenetic trend towards low‐Mg calcite precipitation in intervals of both the marine and freshwater mud. Burial of freshwater mud beneath nearly 3 m of marine mud during rising sea level appears to have preserved a considerable amount of original textures, as compared with younger freshwater deposits now within the transitional brackish‐water setting. Geochemical and textural data within the freshwater mud sections suggest that complex early diagenesis begins shortly after burial at the site of formation, and perhaps even during deposition. The findings herein document three major implications for coastal zone paludal carbonates: (i) that incipient textural diagenesis in low‐Mg calcite crystals can be extremely early and the stability and petrographic fidelity of these deposits are vulnerable due to the open, trellis‐like structure of the crystals; (ii) relatedly, the stable isotope signature of the original low‐Mg calcite crystals is also vulnerable to alteration by secondary precipitation within the open crystal structure; and (iii) during marine transgression, the paludal calcite crystals likely experience a shift from interstitial fluids that are dissolution‐dominated (freshwater) to more precipitation‐dominated as marine fluids overtake the pore fluid regime. Because palustrine deposits are used as palaeoenvironmental archives, it is important to understand their diagenetic and preservation potential. This study has implications for those concerned with the deposition, reactivity and preservation potential of continental and microbial carbonates. [ABSTRACT FROM AUTHOR]

Climate change poses a massive and growing threat to wildlife. Calls are growing for coordinated and collaborative responses to conserve species threatened by climate change, but how this works in practice remains largely unexplored. Focusing on seabirds in North‐West Europe, we carried out 32 semi‐structured stakeholder interviews to (1) explore existing conservation work linked to climate change, (2) identify barriers to work on climate change among conservation actors, and (3) identify key conservation actors and characterize their interactions. Interviewees identified a range of research, policy, and practical conservation work for seabirds related—directly or indirectly—to climate change. They highlighted the importance of general conservation work to facilitate seabird adaptation to climate change, and global mitigation of climate change (e.g., through decarbonization and ecosystem restoration). Interviewees identified several barriers to conservation work explicitly addressing climate change, pertaining to information, leadership, resources, and values/beliefs. We discovered that seabird conservation networks are generally well‐established and harmonious, but not tension‐free. There are also some misunderstandings over actor responsibilities that could lead to bystander effects. We present suggestions to increase the effectiveness and efficiency of seabird conservation in response to climate change. [ABSTRACT FROM AUTHOR]

Dredge is the dominant shellfish fishing gear in Sedati District, this tool has good productivity in the shellfish fishing business. The productivity of fishing gear is related to the ability of fishing gear to provide better catches and the profits obtained by fishermen. This research aims to analyze business finances and the feasibility of shellfish fishing using fishing gear in Sedati Waters, Sidoarjo, East Java, Indonesia. This research used a survey research method with Primary and Secondary data. The samples collected from this study were spread across 224 respondents. The hauling process is carried out while catching shellfish 100-150 times. Shellfish fishing activities are carried out 20-26 days a month. The research results show that the average investment cost for a shellfish fishing business is IDR 31,340,000, fixed costs are IDR 6,988,973 and variable costs are IDR 26,600,000. The shellfish catch obtained by fishermen in one year is around 158 kg - 302 kg, with an average per fisherman of 226 kg consisting of Anadara antiquata, Anadara granosa, and Paratape undulatus batik with a total of IDR 68,380,000. The Net Present Value (NPV) value for the clam fishing business was IDR 75,607,420.00, IRR 72.66%, B/C Ratio 1.39, and the Payback Period was 1.64. By addressing these financial factors, a clam harvesting operation with dredging equipment can be efficiently planned and conducted, ensuring both economic feasibility and operational success. [ABSTRACT FROM AUTHOR]

Sampling and sequencing marine environmental DNA (eDNA) provides a tool that can increase our ability to monitor biodiversity, but movement and mixing of eDNA after release from organisms before collection could affect our inference of species distributions. To assess how conditions at differing spatial scales influence the inferred species richness and compositional turnover, we conducted a paired eDNA metabarcoding and capture (beach seining) survey of fishes on the coast of British Columbia. We found more taxa were typically detected using eDNA compared to beach seining. eDNA identified more taxa with alternative habitat preferences, and this richness difference was greater in areas of high seawater movement, suggesting eDNA has a larger spatial grain influenced by water motion. By contrast, we found that eDNA consistently missed low biomass species present in seining surveys. Spatial turnover of communities surveyed using beach seining differed from that of the eDNA and was better explained by factors that vary at small (10–1000s meters) spatial scales. Specifically, vegetation cover and shoreline exposure explained most species turnover from seining, while eDNA turnover was not explained by those factors and showed a distance decay pattern (a change from 10% to 25% similarity from 2 km to 10 km of distance), suggesting unmeasured environmental variation at larger scales drives its turnover. Our findings indicate that the eDNA sample grain is larger than that of capture surveys. Whereas seining can detect differences in fish distributions at scales of 10s–100s of meters, eDNA can best summarize fish biodiversity at larger scales possibly more relevant to regional biodiversity assessments. [ABSTRACT FROM AUTHOR]

Sponges are a vital source of pharmaceutically active secondary metabolites, of which the main structural types are alkaloids and terpenoids. Many of these compounds exhibit biological activities. Focusing specifically on diterpenoids, this article reviews the structures and biological activities of 228 diterpenes isolated from more than 33 genera of sponges from 2009 to 2022. The Spongia sponges produce the most diterpenoid molecules among all genera, accounting for 27%. Of the 228 molecules, 110 exhibit cytotoxic, antibacterial, antifungal, antiparasitic, anti-inflammatory, and antifouling activities, among others. The most prevalent activity is cytotoxicity, present in 54 molecules, which represent 24% of the diterpenes reported. These structurally and biologically diverse diterpenoids highlight the vast, yet largely untapped, potential of marine sponges in the discovery of new bioactive molecules for medicinal use. [ABSTRACT FROM AUTHOR]

The impact of recreational fisheries on marine ecosystems is often overshadowed by commercial fisheries, although recreational fishing harvest can be substantial, especially for species that are either overfished or experiencing overfishing. Delaware is a small coastal state with ~1,000,000 residents and nearly 272,000 resident and non‐resident anglers. We used publicly available data for Delaware's recreational fisheries during 1981–2021 to determine the nine most caught fish species and to evaluate trends in total numbers caught, harvested, released, and catch per unit effort (CPUE). The top nine most frequently captured fish by recreational anglers were Summer Flounder (Paralichthys dentatus), Atlantic Croaker (Micropogonias undulatus), Bluefish (Pomatomus saltatrix), Black Sea Bass (Centropristis striata), Weakfish (Cynoscion regalis), White Perch (Morone americana), Tautog (Tautoga onitis), Striped Bass (Morone saxatilis), and Spot (Leiostomus xanthurus). The proportion of fish released increased through time for all nine species, suggesting that the recreational fishery in Delaware is transitioning from a harvest‐oriented to a catch‐and‐release‐oriented fishery. Observations of higher release rates in recreational fisheries of Delaware are consistent with the findings elsewhere in the world for freshwater and marine systems. [ABSTRACT FROM AUTHOR]

Sub-Antarctic islands are expected to show a high degree of endemicity due to their remoteness. However, biogeographic affinities in the sub-Antarctic remain poorly understood, especially in the marine realm. Sub-Antarctic islands being at the crossroads between Antarctic and cold temperate regions, biodiversity characterization and biogeographic analyses are a priority for monitoring and rapidly assessing variations associated with environmental changes. One underexplored sub-Antarctic area is Crozet, a protected archipelago located halfway between Antarctica and South Africa. In this study, we investigated the shallow-water Crozet macrofaunal diversity, distribution patterns and biogeographic affinities based on the examination of fieldwork specimens via a thorough morphological identification and a genetic characterisation. The resulting dataset provides an important baseline for further studies and conservation strategies, compiling the first genetic and taxonomic database for the Crozet archipelago. In total, 100 morphotypes were found, belonging to nine different phyla, among which arthropods (32), molluscs (18) and echinoderms (17) were the richest. Forty-seven morphotypes were identified to the species level, among which 20 were reported in Crozet for the first time. This confirms that Crozet is a poorly known region, even compared to other sub-Antarctic areas. A large proportion of species (62%) had circum Southern Ocean or circum subAntarctic distributions. These species were mostly shared with Kerguelen (72%), the Magellan Province (64%), and Prince Edward Islands (64%), confirming the patterns found in macroalgae and specific macrofaunal groups. However, this large-distribution statement needs to be counterbalanced by the detection (genetic data) of more restricted distributions than expected in four study cases (the tanaid Apseudes spectabilis, the nudibranch Doris kerguelenensis, the polychaete Neanthes kerguelensis and the chiton Hemiarthrum setulosum). Considering that most morphotypes had no genetic data available from other regions, the proportion of morphotypes with restricted distribution is likely to increase alongside future investigations. In addition, we also found a few cases of unrecognized diversity that might lead to the descriptions of new species, some likely to be endemic to Crozet (e.g., within the polychaete genus Harmothoe and the bryozoan genus Antarctothoa). Altogether, this stresses the need to maintain conservation efforts in Crozet and pursue integrative investigations in order to highlight and protect its unusual diversity. [ABSTRACT FROM AUTHOR]

DCOIT (4,5-Dichloro-2-octylisothiazol-3(2H)-one) is a widely used antifouling biocide that emerged after the ban on tributyltin. It has been immobilized in nanostructured silica (SiNC–DCOIT) to reduce its hazard in maritime coatings. This study aimed to compare the bioaccumulation, trophic transfer, and biomagnification of DCOIT in its soluble and nanostructured forms on mussels Mytilus galloprovincialis, using three different uptake routes: aqueous exposure (i.e., contaminated seawater), dietary exposure (i.e., microalgae Tetraselmis chuii as a contaminated food), and both contaminated food and seawater. DCOIT was determined on water and tissues after 1, 3, and 24 h of uptake and after 72 h of depuration. Briefly, mussels were able to rapidly uptake and metabolize DCOIT and SiNC–DCOIT. Both compounds were non-bioaccumulative, as their bioconcentration and bioaccumulation factor values were lower than 2000. However, the predator–prey biomagnification factors indicated that both forms could be transferred across the trophic web. Therefore, while our findings provide further insight into the environmental risk assessment of DCOIT and SiNC–DCOIT, they do not rule out the possibility of long-term DCOIT bioaccumulation, particularly in areas with constant DCOIT influx. Further studies are thus needed using larger experimental designs and under continuous exposure scenarios to increase the sustainability of the innovative nanomaterial. [ABSTRACT FROM AUTHOR]

Marine invertebrate stem cells (MISCs) represent a distinct category of pluripotent and totipotent cells with remarkable abilities for self-renewal and differentiation into multiple germ layers, akin to their vertebrate counterparts. These unique cells persist throughout an organism's adult life and have been observed in various adult marine invertebrate phyla. MISCs play crucial roles in numerous biological processes, including developmental biology phenomena specific to marine invertebrates, such as senescence, delayed senescence, whole-body regeneration, and asexual reproduction. Furthermore, they serve as valuable models for studying stem cell biology. Despite their significance, information about MISCs remains scarce and scattered in the scientific literature. In this review, we have carefully collected and summarized valuable information about MISC detection by perusing the articles that study and detect MISCs in various marine invertebrate organisms. The review begins by defining MISCs and highlighting their unique features compared to vertebrates. It then discusses the common markers for MISC detection and in vitro techniques employed in invertebrate and vertebrates investigation. This comprehensive review provides researchers and scientists with a cohesive and succinct overview of MISC characteristics, detection methods, and associated biological phenomena in marine invertebrate organisms. We aim to offer a valuable resource to researchers and scientists interested in marine invertebrate stem cells, fostering a better understanding of their broader implications in biology. With ongoing advancements in scientific techniques and the continued exploration of marine invertebrate species, we anticipate that further discoveries will expand our knowledge of MISCs and their broader implications in biology. [ABSTRACT FROM AUTHOR]

Microplastics are contaminants in marine ecosystems, posing great threats to biota and human health. In this work, we provide an overview of the progress made in understanding microplastic prevalence in tropical coastal environments, focusing on the Johor and the Singapore Straits as a case study. We examine the sources, distribution, transport, and ecological impact of microplastic pollution in this region through a systematic review. All papers relating to marine microplastics in Singapore's sand and benthic sediments, seawater, and marine biota were used for analysis, from 2004 to 2023. In addition, we discuss the influence of envi-ronmental factors such as coastal morphology and anthropogenic activities on patterns of microplastic accumulation. We emphasize that microplastic pollution is more prevalent along the eutrophic Johor Strait compared to the Singapore Strait due to hydrological conditions. Rainfall is also a key factor that influences mi-croplastic abundance during the monsoon seasons. Furthermore, the bacterial and plankton assemblages of organisms on microplastic surfaces are diverse, with eutrophic waters enhancing the diversity of organisms on microplastic surfaces. Novel harmful cyanobacteria and bloom species of phytoplankton were also found on microplastic surfaces. By synthesizing existing research findings and highlighting regional characteristics, this paper contributes to ongoing efforts to mitigate microplastic pollution in tropical regions. [ABSTRACT FROM AUTHOR]

Anthropogenic biodiversity loss can impair ecosystem functioning. Human activities are often managed with the aim of reversing biodiversity loss and its associated functional impacts. However, it is currently unknown whether biodiversity–ecosystem function (BEF) relationships observed during biodiversity recovery are the same as those observed during biodiversity loss. This will depend on how species extirpation and recolonisation sequences compare and how different species influence ecosystem functioning. Using data from a marine benthic invertebrate community, we modelled how bioturbation potential – a proxy for benthic ecosystem functioning – changes along biodiversity loss and recovery sequences governed by species' sensitivity to physical disturbance and recolonisation capability, respectively. BEF relationships for biodiversity loss and recovery were largely the same despite species extirpation and recolonisation sequences being different. This held true irrespective of whether populations were assumed to exhibit compensatory responses as species were removed or added. These findings suggest that the functional consequences of local biodiversity loss can be reversed by alleviating its drivers, as different species present at comparable levels of species richness during biodiversity loss and recovery phases have similar functional effects. Empirically verifying and determining the generality of our model‐based results are potential next steps for future research. [ABSTRACT FROM AUTHOR]

The urgency of multidrug-resistant (MDR) bacterial infections in wounds is a significant concern due to the high prevalence of MDR in healthcare settings. Black pigmented marine bacteria, strain PS1C, were isolated from marine sediment on Awur Beach Jepara, Central Java, Indonesia, and cultured in the laboratory. The aim of this research includes molecular identification of strain PS1C, extracting black pigment from strain PS1C, isolation of MDR bacteria from wounds, and evaluating the antibacterial activity of black pigment from strain PS1C against MDR bacteria isolates of wound infections. We examined the 16S rRNA gene sequences strain PS1C to identify the species. Then, the black pigment from PS1C was extracted using methanol: acetone (7:3) solvent. Antibacterial activity was evaluated against MDR bacteria from wounds with the microdilution method. A black-pigmented bacterium was isolated and identified as Pseudomonas aeruginosa PS1C. We found that the black pigment from P. aeruginosa PS1C can be developed as an antibacterial agent against the MDR bacterial isolate of wounds with MIC and MBC values of 6.25-12.5 mg/ml and 6.25-25 mg/ml, respectively. In conclusion, the study's findings highlight the potential of the extract of black pigment from P. aeruginosa PS1C as an antibacterial agent against wound-causing MDR bacteria and reinforce previous research into P. aeruginosa can be isolated from marine sources. Additional in vivo investigations and the identification of the antibacterial activity's mode of action are required. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are one of the major substantial pollutants in the environment and are stored in sediments worldwide, especially in marine environments. This study shed light on the abundance, distribution, sources and chemical composition of MPs present in the surface sediments collected from the shelf part of the southeast coast of India, Bay of Bengal. A total of twenty-seven surface sediment samples were collected to study MPs pollution. The abundance and morphological characteristics of MPs were determined by counting using an Olympus SXZ7 stereo microscope. Raman spectroscopy analysis was used to identify the polymer type of the MPs. The average abundance of MPs in the study area is 460±275 MPs/kg in dry sediment. Regarding colour, transparent particles were predominant (46.42%), followed by blue, green, brown, etc. With respect to particle shape and size, fibres and 500-µm sized MPs are abundant. Polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene (PS) are the polymer types characterised in the study area. The higher abundance of MPs in the study area can be attenuated to human interruptions, viz., tourism, fishing and inappropriate sewage disposal in the marine environment. In addition to this, population density also plays an important role in providing MPs to the marine environment. This study provides the most valuable data to extrapolate the research for mitigating MP pollution in oceans. It also informs mankind about their disastrous activities on the marine environment, which is expected to recuperate quickly and negatively impact human health and the functionality of the marine system. [ABSTRACT FROM AUTHOR]

Aim: Substantial progress has been made to map biodiversity and its drivers across the planet at multiple scales, yet studies that quantify the evolutionary processes that underpin this biodiversity, and test their drivers at multiple scales, are comparatively rare. Studying most fish species, we quantify rates of body size evolution to test the role of fundamental salinity habitats in shaping rates of evolution at multiple scales. We also determine how four additional factors shape evolutionary rates. Location: Global. Time Period: Extant species. Major Taxa Studied: Actinopterygii. Methods: In up to 1710 comparisons studying over 27,000 species, we compare rates of body size evolution among five salinity habits using 13 metrics. The comparisons span a molecular tree, 100 supertrees, and 10 scales of observation to test for robust patterns and reveal how patterns change with scale. Then, three approaches assess the role of three non‐salinity factors on rates, and an alternative habitat scheme tests if lakes influence evolutionary rates. Results: Rates of size evolution rarely differ consistently between salinity habitats; rate patterns are highly clade‐ and scale dependent. One exception is freshwater‐brackish fishes, which possess among the highest size rates of any salinity, showing higher rates than euryhaline fishes in most groupings studied at most scales, and versus marine, freshwater and marine–brackish habitats at numerous scales. Additionally, species richness had the greatest potential to predict phenotypic rates, followed by branch duration, then absolute values of body size. Lacustrine environments were consistently associated with high rates of size evolution. Main Conclusions: We reveal the rate patterns that underpin global body size diversity for fishes, identifying factors that play a limited role in shaping rates of size evolution, such as salinity, and those such as species richness, age and lake environments that consistently shape evolutionary rates across half of vertebrate diversity. [ABSTRACT FROM AUTHOR]

The characterization of digestive enzymes presents in fish and their potential biotechnological uses is a welldeveloped and studied field. However, there has not been a systematic review that analyzes the state of knowledge of these enzymes at a global level. Therefore, a systematic literature search on three platforms was carried out to review and analyze existing knowledge about digestive enzymes of marine fishes from fisheries and aquaculture and their potential application in industrial processes. Using the PRISMA method for selecting journal manuscripts, we found 112 scientific articles published between 1984 and 2020 studying different digestive enzymes from 87 fish species. Most studies were carried out in Tunisia and Mexico and only 6 articles were published in South American countries. The most studied digestive enzymes were alkaline proteases, mainly trypsin, and the proposed uses for these enzymes were mainly as additives in commercial detergents. There is a vacancy in the characterization of other digestive enzymes as pepsins, lipases and amylases and the study of species that are distributed in the Southwest Atlantic Ocean. It is necessary to expand the knowledge about other digestive enzymes and to carry out new studies in regions with an important fishery development. [ABSTRACT FROM AUTHOR]

Despite often being referred to as a ‘coolhouse climate’, the climate during the Miocene (23.03–5.33 Ma) was overall humid, warm and temperate. It was paced by orbitally driven cooler periods (the Oligocene–Miocene Transition and Mi-events) overprinted by a climatic optimum. Global cooling during the Late Miocene brought more arid conditions with climate seasonality, which varied across western Eurasia. Sedimentary archives from onshore Denmark comprise shallow marine siliciclastic deposits and discrete brown coal layers. Hence, they allow us to infer past climates and environments using both marine and terrestrial fossils. The backbone for Miocene stratigraphy and palaeoclimate reconstruction in the eastern North Sea Basin (present-day Denmark) is the Sønder (Sdr.) Vium sediment core, which penetrates a shallow marine succession and spans an interval from c. 22 to 8 Ma. Here, we present an improved age model for the core. During the Miocene, forested lowlands predominated in the eastern North Sea Basin. Coastal areas included rich riparian landscapes and delta areas of lignite-forming swamp forest. Compilations of existing proxy records (pollen, spores, leaves, plant fragments and the organic biomarkers alkenones and membrane lipids) collectively show that the climate here was warm and moist during the Early and Middle Miocene, while the Late Miocene was characterised by climate cooling and modernisation of the vegetation. The interval preceding the Miocene Climatic Optimum was already warm and moist, and the onset was not characterised by a significant increase in temperature and precipitation. Instead, the palynoflora indicates homogeneous vegetation and only a weak signal of warming shown by a minor increase of, for example, sabaloid palms and Mastixiaceae.

The characterization of digestive enzymes presents in fish and their potential biotechnological uses is a well-developed and studied field. However, there has not been a systematic review that analyzes the state of knowledge of these enzymes at a global level. Therefore, a systematic literature search on three platforms was carried out to review and analyze existing knowledge about digestive enzymes of marine fishes from fisheries and aquaculture and their potential application in industrial processes. Using the PRISMA method for selecting journal manuscripts, we found 112 scientific articles published between 1984 and 2020 studying different digestive enzymes from 87 fish species. Most studies were carried out in Tunisia and Mexico and only 6 articles were published in South American countries. The most studied digestive enzymes were alkaline proteases, mainly trypsin, and the proposed uses for these enzymes were mainly as additives in commercial detergents. There is a vacancy in the characterization of other digestive enzymes as pepsins, lipases and amylases and the study of species that are distributed in the Southwest Atlantic Ocean. It is necessary to expand the knowledge about other digestive enzymes and to carry out new studies in regions with an important fishery development.

Saponins encompass a diverse group of naturally occurring glycoside molecules exhibiting amphiphilic properties and a broad range of biological activities. There is a resurgence of interest in those saponins produced by marine organisms based on their potential therapeutic benefits, application in food products and most recently their potential involvement in intra- and inter-species chemical communication. The continual advancements in liquid chromatography techniques and mass spectrometry technologies have allowed for greater detection rates, as well as improved isolation and elucidation of saponins. These factors have significantly contributed to the expansion in the catalogue of known saponin structures isolated from marine invertebrates; however, there currently exists no specific chemical library resource to accelerate the discovery process. In this study, a Marine Animal Saponin Database (MASD v1.0) has been developed to serve as a valuable chemical repository for known marine saponin-related data, including chemical formula, molecular mass and biological origin of nearly 1000 secondary metabolites associated with saponins produced by marine invertebrates. We demonstrate its application with an exemplar asteroid extract (Acanthaster cf. solaris, also known as crown-of-thorns starfish; COTS), identifying saponins from the MASD v1.0 that have been previously reported from COTS, as well as 21 saponins isolated from multiple other related asteroid species. This database will help facilitate future research endeavours, aiding researchers in exploring the vast chemical diversity of saponins produced by marine organisms and providing ecological insights, and the realisation of their potential for various applications, including as pharmaceuticals. [ABSTRACT FROM AUTHOR]

Abstract Background Gemmatimonadota bacteria are widely distributed in nature, but their metabolic potential and ecological roles in marine environments are poorly understood. Results Here, we obtained 495 metagenome-assembled genomes (MAGs), and associated viruses, from coastal to deep-sea sediments around the world. We used this expanded genomic catalog to compare the protein composition and update the phylogeny of these bacteria. The marine Gemmatimonadota are phylogenetically different from those previously reported from terrestrial environments. Functional analyses of these genomes revealed these marine genotypes are capable of degradation of complex organic carbon, denitrification, sulfate reduction, and oxidizing sulfide and sulfite. Interestingly, there is widespread genetic potential for secondary metabolite biosynthesis across Gemmatimonadota, which may represent an unexplored source of novel natural products. Furthermore, viruses associated with Gemmatimonadota have the potential to “hijack” and manipulate host metabolism, including the assembly of the lipopolysaccharide in their hosts. Conclusions This expanded genomic diversity advances our understanding of these globally distributed bacteria across a variety of ecosystems and reveals genetic distinctions between those in terrestrial and marine communities. Video Abstract

Microplastics are contaminants in marine ecosystems, posing great threats to biota and human health. In this work, we provide an overview of the progress made in understanding microplastic prevalence in tropical coastal environments, focusing on the Johor and the Singapore Straits as a case study. We examine the sources, distribution, transport, and ecological impact of microplastic pollution in this region through a systematic review. All papers relating to marine microplastics in Singapore’s sand and benthic sediments, seawater, and marine biota were used for analysis, from 2004 to 2023. In addition, we discuss the influence of envi-ronmental factors such as coastal morphology and anthropogenic activities on patterns of microplastic accumulation. We emphasize that microplastic pollution is more prevalent along the eutrophic Johor Strait compared to the Singapore Strait due to hydrological conditions. Rainfall is also a key factor that influences mi-croplastic abundance during the monsoon seasons. Furthermore, the bacterial and plankton assemblages of organisms on microplastic surfaces are diverse, with eutrophic waters enhancing the diversity of organisms on microplastic surfaces. Novel harmful cyanobacteria and bloom species of phytoplankton were also found on microplastic surfaces. By synthesizing existing research findings and highlighting regional characteristics, this paper contributes to ongoing efforts to mitigate microplastic pollution in tropical regions.

Piemonte is widely acknowledged as a remarkable Pliocene palaeontological spot, due to its potential for the observation and study of marine and terrestrial fossils in abundant outcrops. Our observations on about 80 palaeobotanical localities, representing both terrestrial and marine sedimentary deposits, show that some of them could easily provide more significant materials than those available today. About 30 plant-bearing Pliocene sites were selected for morphological analyses on plant fossils, mainly leaf remains. The main features of each assemblage, including the systematic placement of about 400 plant samples within 52 taxa, are indexed and described in this paper, by combining analysis of palaeontological collections and field observations. The results obtained so far encourage further studies in specific areas of palaeobotanical interest, whose results could easily provide major palaeoenvironmental insights. Finally, we suggest considering more carefully the Piemonte palaeobotanical sites in the frame of geoconservation strategies and we point out the relevance of ex-situ protection of endangered plant fossil samples (collections) in order to assure their availability for future studies.

Laminarin is a cytosolic storage polysaccharide of phytoplankton and macroalgae and accounts for over 10% of the world's annually fixed carbon dioxide. Algal disruption, for example, by viral lysis releases laminarin. The soluble sugar is rapidly utilized by free-living planktonic bacteria, in which sugar transporters and the degrading enzymes are frequently encoded in polysaccharide utilization loci. The annotation of flavobacterial genomes failed to identify canonical laminarin utilization loci in several particle-associated bacteria, in particular in strains of Maribacter. In this study, we report in vivo utilization of laminarin by Maribacter forsetii accompanied by additional cell growth and proliferation. Laminarin utilization coincided with the induction of an extracellular endo-laminarinase, SusC/D outer membrane oligosaccharide transporters, and a periplasmic glycosyl hydrolase family 3 protein. An ABC transport system and sugar kinases were expressed. Endo-laminarinase activity was also observed in Maribacter sp. MAR_2009_72, Maribacter sp. Hel_I_7, and Maribacter dokdonensis MAR_2009_60. Maribacter dokdonensis MAR_2009_71 lacked the large endolaminarinase gene in the genome and had no endo-laminarinase activity. In all genomes, genes of induced proteins were scattered across the genome rather than clustered in a laminarin utilization locus. These observations revealed that the Maribacter strains investigated in this study participate in laminarin utilization, but in contrast to many free-living bacteria, there is no co-localization of genes encoding the enzymatic machinery for laminarin utilization. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The growing atmospheric mercury (Hg) emissions in China have raised ongoing concerns regarding contamination in marine fish. To better understand the pollution patterns and associated risks, we examined methylmercury (MeHg) content in demersal and pelagic fish from four commonly found families in three geographically distinct bays along the Chinese coast. We identified significant spatial variations in MeHg levels within the same fish family across regions. Specifically, fish collected from the Beibu Gulf in the South China Sea consistently exhibited significantly higher MeHg levels compared to those from the Laizhou Bay in the Northeast and/or Haizhou Bay in the East of China. In contrast, MeHg levels in fish collected from Haizhou Bay consistently remained the lowest. Within each region, we observed significantly higher MeHg concentrations in demersal species compared to pelagic species. This trend was particularly evident in fish species including bartail flathead (Platycephalus indicus), small-scale tongue sole (Cynoglossus microlepis) and greater lizardfish (Saurida tumbil) from the Beibu Gulf (0.50, 0.21, and 0.18 mg/kg dw, respectively), as well as bartail flathead and slender lizardfish (Saurida elongata) from Laizhou Bay (0.09 and 0.12 mg/kg dw, respectively). By comparison, MeHg content in silver pomfret (Pampus argenteus) from all three regions consistently remained relatively lower than in other species. Using target hazardous quotient (THQ) calculations, we estimated potential health risks in local populations associated with the consumption of the studied fish species. Our results showed a lack of apparent health risks to local residents, as all THQ values obtained from the three regions fell within the safe limits (0.02-0.94). However, it remains important to conduct additional assessments and spatiotemporal monitoring that encompass a broader range of species and regions. [ABSTRACT FROM AUTHOR]

Background: Gemmatimonadota bacteria are widely distributed in nature, but their metabolic potential and ecological roles in marine environments are poorly understood. Results: Here, we obtained 495 metagenome-assembled genomes (MAGs), and associated viruses, from coastal to deep-sea sediments around the world. We used this expanded genomic catalog to compare the protein composition and update the phylogeny of these bacteria. The marine Gemmatimonadota are phylogenetically different from those previously reported from terrestrial environments. Functional analyses of these genomes revealed these marine genotypes are capable of degradation of complex organic carbon, denitrification, sulfate reduction, and oxidizing sulfide and sulfite. Interestingly, there is widespread genetic potential for secondary metabolite biosynthesis across Gemmatimonadota, which may represent an unexplored source of novel natural products. Furthermore, viruses associated with Gemmatimonadota have the potential to "hijack" and manipulate host metabolism, including the assembly of the lipopolysaccharide in their hosts. Conclusions: This expanded genomic diversity advances our understanding of these globally distributed bacteria across a variety of ecosystems and reveals genetic distinctions between those in terrestrial and marine communities. -srP_8yBftBuaKffV-GvkT Video Abstract [ABSTRACT FROM AUTHOR]

Societal Impact Statement Summary Seagrass meadows are a globally important habitat subject to significant loss. As efforts to restore these sensitive habitats are hampered by their high cost and low levels of reliability, rigorous guidance is required to improve effectiveness and ensure they are cost‐effective. Here, we define 10 golden rules for how we can undertake seagrass restoration. We do this by considering that for seagrass restoration to be successful, it needs to take place with people and not against people. The framework we present aims to direct efforts for seagrass restoration that are holistic and achieve broad goals for people, biodiversity and the planet.The world has lost a significant proportion of its seagrass, and although glimmers of hope for its recovery exist, losses and degradations continue. First and foremost, evidence highlights the need to put the world on a global pathway to seagrass net gain. Achieving this outcome requires that conservation of what remains is a priority, but reaching net gain requires seagrass coverage to increase at rates unlikely to be achieved naturally; large‐scale active restoration is required to fill this gap. Novel finance mechanisms aligned to the climate emergency and biodiversity crises are increasingly leading to larger scale restoration projects. However, no clear framework exists for developing or prioritising approaches. With seagrass restoration expensive and unreliable, rigorous guidance is required to improve effectiveness and ensure it is cost‐effective. Building on evidence from terrestrial and marine sources, here, we apply the ‘10 golden rules’ concept, first outlined for reforestation and later applied to coral reefs, to seagrass restoration. In doing so, we follow international standards for ecological restoration and view seagrass restoration in a broad context, whereby regeneration can be achieved either by planting or by enhancing and facilitating natural recovery. These rules somewhat differ from those on reforestation and coral reef restoration, principally due to the relative immaturity of seagrass restoration science. These 10 golden rules for seagrass restoration are placed within a coupled social‐ecological systems context, and we present a framework for conservation more broadly, to achieve multiple goals pertaining to people, biodiversity and the planet. [ABSTRACT FROM AUTHOR]

Aim: Understanding the factors determining marine community variations is important for biogeography and conservation. Beta diversity is a metric for mapping species composition variations between communities and regionalizing biota. Ecoregions are commonly used for regionalization, but their empirical testing has been limited. Our aim is to map marine species composition variations in the Western Atlantic, identify variables related to these variations, and regionalize areas based on community distribution. Additionally, we test whether currently proposed ecoregions represent unique biota units and specific environmental conditions. Location: Western Atlantic Ocean. Taxon: Vertebrates, invertebrates and algae. Methods: We constructed a large marine biodiversity database, including vertebrates, invertebrates, and algae, totalling over 4 million records. We used the generalized dissimilarity model (GDM) to identify variables most related to species composition variations and map beta‐diversity variations. We employed an unsupervised classifier for community regionalization. To test if the ecoregion regionalization boundaries are corroborated by species distribution data, we used the Sørensen index. To assess if ecoregions correspond to environmental units, we checked if areas had distinct environmental conditions using a PCA of 134 marine environmental variables. Results: The GDM explained a high variation in species composition, 61% in the complete database. Analysing vertebrates, invertebrates and algae separately also yielded relatively high results: 46%, 54%, and 33%, respectively. Coastal areas differed from open sea areas in composition. Environmental variables combined better explained beta diversity than isolated variables. The regionalization based on GDM was not congruent with ecoregion boundaries. Moreover, ecoregions showed no distinction in species composition or environmental conditions. Main Conclusions: This study's regionalization is crucial for marine biodiversity conservation, focusing on understanding species composition patterns between coastal and open sea areas to develop tailored conservation strategies. Despite sampling limitations, the study advances marine biogeography knowledge by analysing over 4 million species records and 134 environmental variables. This comprehensive approach enhances understanding marine species distribution and diversity and aiding the development of effective conservation measures. [ABSTRACT FROM AUTHOR]

Man-made structures in the marine environment such as offshore Oil & Gas infrastructure are known to provide a hard substrate that enables ecosystems to develop on and around them. Current decommissioning practices on the UK Continental Shelf are mandated by the OSPAR Decision 98/3 with the premise of a clean seabed at its core, meaning that it is the expectation that all infrastructure is completely removed at the end of its operation life, leaving a clear seabed behind. This study critically reviewed 49 peer-reviewed articles relating to the ecosystem and the impact to these ecosystems by current removal practices. The results clearly demonstrate that current science-based evidence shows that existing O&G platform substructures act as multipurpose artificial reefs upon which rich ecosystems have developed and that their removal degrades the overall North Sea marine environment. Furthermore, this study shows that clearsea bed policies, such as OSPAR 98/3, do not reflect, nor understand the complex relationship and interdependencies between biology and man-made structures and do not reflect current scientific knowledge. It is concluded that based on current knowledge, it is no longer scientifically justifiable to mandate the removal of all O&G infrastructure during decommissioning and that applying the principle of a clean seabed according to the OSPAR Commission should be re-considered. [ABSTRACT FROM AUTHOR]

Currently, there is an urgent need for new antibacterial and antifungal agents to combat the growing challenge of antibiotic resistance. As the largest ecosystem on Earth, the marine ecosystem includes a vast array of microorganisms (primarily bacteria and fungi), plants, invertebrates, and vertebrates, making it a rich source of various antimicrobial compounds. Notably, terpenoids, known for their complex structures and diverse bioactivities, are a significant and promising group of compounds in the battle against bacterial and fungal infections. In the past five years, numerous antimicrobial terpenoids have been identified from marine organisms such as bacteria, fungi, algae, corals, sea cucumbers, and sponges. This review article provides a detailed overview of 141 terpenoids with antibacterial and/or antifungal properties derived from marine organisms between 2019 and 2024. Terpenoids, a diverse group of natural organic compounds derived from isoprene units, are systematically categorized based on their carbon skeleton structures. Comprehensive information is provided about their names, structures, biological sources, and the extent of their antibacterial and/or antifungal effectiveness. This review aims to facilitate the rapid identification and development of prospective antimicrobials in the pharmaceutical sector. [ABSTRACT FROM AUTHOR]

The compressor volume flow rate model determines the mass flowing into the diesel engine in simulation. It is a key component model that affects the accuracy of the overall performance of the diesel engine. At present, there is a lack of an accurate and easy-to-use compressor volume flow rate model. To solve this, the stagnation enthalpy-based compressor volume flow rate model (SP model) is proposed. The SP model is compared with an improved version of the famous empirical JENSEN model, M-JENSEN (MJ), and physics-based KS model. The proposed SP model only requires the stagnation pressure to be determined. The empirical M-JENSEN model needs a compressor map to optimize its six parameters. The physics-based KS model requires specific work to be determined. The SP model needs the least measured data and is easy to be identified. Models' accuracy comparison on ABB A270 shows that the proposed SP model can generate the compressor map with RMSE of about 1.1m3/s and mean relative error (MRE) of about 6.9%. The rated volume flow rate of ABB A270 is about 20m3/s. While the RMSE and MRE of MJ model are about 0.6m3/s and 3.1% respectively. And they are about 3.0m3/s and 17.4% for KS model. When the model's accuracy is compared to MAN TCA88, SP model shows slightly better performance than its performance on ABB A270. The rated volume flow rate of MAN TCA88 is about 60m3/s. The values of RMSE of SP model, MJ model, and KS model are 3.2m3/s, 2.2m3/s, 10.3m3/s respectively. Their MREs are 6.73%, 4.45%, and 17.8% respectively. In terms of these results, it can be concluded that our proposed SP model needs the least data, easy to code, and has excellent performance. It is one of the best compressor mass flow rate models so far in real-time diesel simulation. [ABSTRACT FROM AUTHOR]

Many studies have consistently demonstrated that the near-surface phytoplankton chlorophyll (Chl) levels in anticyclonic eddies (AEs) are higher than in cyclonic eddies (CEs) in the South Pacific Ocean (SPO), using remote sensing data, which is attributed to higher phytoplankton biomass or physiological adjustments in AEs. However, the characteristics of the Chl profile induced by mesoscale eddies and their underlying dynamic mechanism have not been comprehensively studied by means of field measurement, and the influence mechanism of environmental factors at different depths on Chl has not been investigated. To fill this gap, we utilized Biogeochemical-Argo (BGC-Argo) data to investigate the relationships between Chl concentration and environmental factors at different water layers and the underlying dynamic mechanisms of mesoscale eddies in the SPO. Our findings indicate that the same environmental factor can have different effects on Chl at different depths. Within a mixed layer (ML), the elevated Chl levels in AEs result from both physiological adjustments and increased phytoplankton biomass, and the former plays a more dominant role, which is induced by enhanced nutrient availability and weakened light, due to the deepening ML in AEs. At depths ranging from 50 m to 110 m, and between 110 m and 150 m (near the depth of pycnocline or the bottom of the euphotic zone), the dominant factor contributing to higher Chl levels in CEs is phytoplankton physiological adaptation driven by reduced temperature and light. At depths exceeding 150 m (beyond the euphotic zone), higher Chl in AEs is primarily caused by high phytoplankton biomass as a result of downwelling by eddy pumping. This work should advance our comprehensive understanding of the physical–biological interactions of mesoscale eddies and their impacts on primary productivity throughout the water column, and it should provide some implications for understanding the biogeochemical processes. [ABSTRACT FROM AUTHOR]

The United Nations’ Declaration on the Rights of Indigenous Peoples (UNDRIP) recognized Indigenous rights to self-determination. How these rights can be realized in territories governed by settler-states remains unclear. For fisheries, the need to understand processes that support Indigenous self-determination has gained urgency due to government commitments and investor interest in developing ocean and coastal resources, or Blue Economies, amid rapid climatic changes. Here, we explored Indigenous groups’ fishery development experiences following two approaches to reconciling Indigenous fishing rights. In New Zealand, we examined Māori groups’ experiences following the 1992 Treaty of Waitangi (Fisheries Claims) Settlement Act. The Settlement granted Māori iwi (tribes) rights to self-govern non-commercial harvests, restrict fishing pressure in state-approved customary fishing areas, and participate in state-run systems for commercial fisheries management. In Canada, we investigated Indigenous fishery development initiatives following the Supreme Court of Canada’s 1999 ruling R. v. Marshall. Marshall reaffirmed Treaty-protected rights to harvest and trade fish, held by Mi’kmaq, Wolastoqey, and Peskotomuhkati Peoples, to support a “moderate livelihood.” We document how, in both cases, Indigenous groups’ self-determination remains constrained by actions from state regulatory and enforcement agencies that govern market access, other resource users’ activities, and processes for collecting and sharing information about fish populations. Indigenous groups’ experiences highlight that: 1) reallocations of harvest rights, on their own, are an insufficient means to redistribute access to benefits from fisheries; 2) the constraints Indigenous families have experienced in their attempts to develop small-scale fishing operations correspond to settler-state policies and cannot be addressed solely through changes to Indigenous leaders’ management decisions; and 3) polycentricity in governance regimes can pose problems for Indigenous self-determination, when citizens with political authority resist efforts to support Indigenous fisheries. To address these challenges, we call for legal reforms that require settler-state governments to support Indigenous self-determination, to overcome the political risks politicians face when advocating for a non-majority group’s interests. [ABSTRACT FROM AUTHOR]

Epithelial ovarian cancer (EOC) is a common gynecological cancer and a leading cause of death, especially because the tumors develop resistance to cisplatin. New compounds are needed to achieve better disease control and survival. We examined the cytotoxic effect of Gallic acid (GA), Hymenialdisine, and Malformin A1 (MA1) on human ovarian cancer cells. Cytotoxicity was tested using cisplatin-sensitive (A2780s) and cisplatin-resistant (A2780cp) ovarian cancer cell lines, and a normal ovarian tissue cell line (HOSE6-3) using AlamarBlue assay, Hoechst dye, and flow cytometry, and the genes and proteins of interest were assessed using western blot, and qRTPCR. The IC50 of Hymenialdisine was 146.8 μM for A2780s cells and >300 μM for A2780cp cell lines. Both GA and MA1 decreased cell viability in a concentration-dependent manner. The IC50 of GA was 103 μM for A2780s cells, 189 μM for A2780cp cells and 262 μM for HOSE6-3 cell lines, for MA1 IC50 was 0.23 μM for A2780s and 0.34 μM for A2780cp. This was in comparison to IC50 of 31.4 μM and 76.9 μM, for A2780s cells, and A2780cp cells respectively for cisplatin. The combination of GA and MA1 with cisplatin revealed synergistic action, especially in A2780cp cell lines. The results suggest that both GA and MA1 may help overcome the resistance to cisplatin through the synergistic effect. Hence, the cytotoxic potential of GA and MA1 merit further investigation. [ABSTRACT FROM AUTHOR]

Curracurrang 1 (1CU5) is a rockshelter site located in the Royal National Park (RNP) on the coast south of Sydney. Excavated from 1962 to 1966, the site's rich Holocene cultural deposit has become important for understanding regional Late Holocene developments in Australian lithic and shell technologies. Our comprehensive analysis of 1CU5's faunal remains is presented here, accompanied by new AMS radiocarbon dates and a reinterpretation of the site's occupation sequence. Much of the midden deposit spans from about 2500 BP to approximately 1850 AD, rather than only the last ∼1500 years as originally believed based on less comprehensive dating. A wide range of terrestrial and marine fauna were exploited at 1CU5, with the relative importance of the latter group increasing within the last ∼1500 years. Greater fish consumption during the later period may relate to use of novel hook and line fishing technology using hooks made from shellfish, but concurrent increases in seals, seabirds and marine invertebrates suggest a broader increased reliance on marine resources. By comparison, the earlier period, which coincides with the manufacture of backed microliths, displays relatively greater reliance on terrestrial marsupials. Taxonomic representation suggests occupation of the shelter from winter through spring, and potentially into summer. Analysis of the 1CU5 fauna marks an important contribution to the understanding of Late Holocene economies at the interface of the greater Sydney and NSW South Coast cultural and biogeographic regions. [ABSTRACT FROM AUTHOR]

Radioactive materials may contain primordial radionuclides, and radionuclides of anthropogenic, nuclear accident, and waste disposal which are present in marine environments. This review explores various approaches for the effective sampling and detection of marine radionuclides. The different types of samples that can be collected, including water, sediment, biota, and suspended particulate matter are discussed. Additionally, this paper discusses the various analytical techniques employed for radionuclide detection, such as gamma spectrometry and radiochemical separation. The review emphasizes the importance of choosing appropriate sampling and detection methods based on the specific radionuclides, environmental conditions, and the desired level of sensitivity. It also highlights the challenges associated with their sampling and detection in complex marine environments. These include low radionuclide concentrations, interference from natural matrices, and contamination risks. [ABSTRACT FROM AUTHOR]

Every year, the global production of plastic waste reaches a staggering 400 million metric tons (Mt), precipitating adverse consequences for the environment, food safety, and biodiversity as it degrades into microplastics (MPs). The multifaceted nature of MP pollution, coupled with its intricate physiological impacts, underscores the pressing need for comprehensive policies and legislative frameworks. Such measures, alongside advancements in technology, hold promise in averting ecological catastrophe in the oceans. Mandated legislation represents a pivotal step towards restoring oceanic health and securing the well‐being of the planet. This work offers an overview of the policy hurdles, legislative initiatives, and prospective strategies for addressing global pollution due to MP. Additionally, this work explores innovative approaches that yield fresh insights into combating plastic pollution across various sectors. Emphasizing the importance of a global plastics treaty, the article underscores its potential to galvanize collaborative efforts in mitigating MP pollution's deleterious effects on marine ecosystems. Successful implementation of such a treaty could revolutionize the plastics economy, steering it towards a circular, less polluting model operating within planetary boundaries. Failure to act decisively risks exacerbating the scourge of MP pollution and its attendant repercussions on both humanity and the environment. Central to this endeavor are the formulation, content, and execution of the treaty itself, which demand careful consideration. While recognizing that a global plastics treaty is not a panacea, it serves as a mechanism for enhancing plastics governance and elevating global ambitions towards achieving zero plastic pollution by 2040. Adopting a life cycle approach to plastic management allows for a nuanced understanding of possible trade‐offs between environmental impact and economic growth, guiding the selection of optimal solutions with socio‐economic implications in mind. By embracing a comprehensive strategy that integrates legislative measures and technological innovations, we can substantially reduce the influx of marine plastic litter at its sources, safeguarding the oceans for future generations. Practitioner Points: Microplastic pollution is an invisible threat to food safety and biodiversity.Effective policy instruments can prevent MPs pollution from widespread.Legislation can reduce plastic waste at source and promote circular economy.Through a global treaty, the world can protect marine‐protected areas and biodiversity. [ABSTRACT FROM AUTHOR]