Dispersal of Late Triassic clam shrimps across Pangea linking northwestern Gondwana and central Pangea rift basins.

Clam shrimps are a group of freshwater crustaceans who prospered during the Late Triassic. They were abundant in lacustrine sedimentary records of continental basins distributed throughout Pangea during this time. However, they show significant taxonomic differences between the clamp shrimp faunas from the rift basins of central Pangea and the southern Gondwanan basins. In this contribution, we show new fossil clam shrimp assemblages from the lacustrine sedimentary successions of the Eastern Cordillera of Colombia (the Bocas and Montebel formations), providing information on the Late Triassic species that inhabited the northwestern Gondwana basins. This study demonstrates that the basins of northwestern Gondwana shared Norian clamp shrimp species with rift basins of central Pangea and differed in their faunas with the basins of the southern portion of Gondwana. In addition, the Late Triassic clam shrimps paleobiogeographic distribution reflects the dispersal of this fauna throughout fluvial-lacustrine environments established in the rift valleys along the central Pangea. Therefore, the rift valleys produced during the early fragmentation of central Pangea could have acted as corridors for dispersion. Simultaneously, rift valleys also provided paleobiogeographic barriers that isolated the central Pangea clam shrimp faunas from southern Gondwana.

Long-term balancing selection for pathogen resistance maintains trans-species polymorphisms in a planktonic crustacean.

Balancing selection is an evolutionary process that maintains genetic polymorphisms at selected loci and strongly reduces the likelihood of allele fixation. When allelic polymorphisms that predate speciation events are maintained independently in the resulting lineages, a pattern of trans-species polymorphisms may occur. Trans-species polymorphisms have been identified for loci related to mating systems and the MHC, but they are generally rare. Trans-species polymorphisms in disease loci are believed to be a consequence of long-term host-parasite coevolution by balancing selection, the so-called Red Queen dynamics. Here we scan the genomes of three crustaceans with a divergence of over 15 million years and identify 11 genes containing identical-by-descent trans-species polymorphisms with the same polymorphisms in all three species. Four of these genes display molecular footprints of balancing selection and have a function related to immunity. Three of them are located in or close to loci involved in resistance to a virulent bacterial pathogen, Pasteuria, with which the Daphnia host is known to coevolve. This provides rare evidence of trans-species polymorphisms for loci known to be functionally relevant in interactions with a widespread and highly specific parasite. These findings support the theory that specific antagonistic coevolution is able to maintain genetic diversity over millions of years.

New records of non-indigenous species from the eastern Mediterranean Sea (Crustacea, Mollusca), with a revision of genus Isognomon (Mollusca: Bivalvia).

We report new data on non-indigenous invertebrates from the Mediterranean Sea (four ostracods and 20 molluscs), including five new records for the basin: the ostracods Neomonoceratina iniqua, Neomonoceratina aff. mediterranea, Neomonoceratina cf. entomon, Loxoconcha cf. gisellae (Arthropoda: Crustacea)-the first records of non-indigenous ostracods in the Mediterranean-and the bivalve Striarca aff. symmetrica (Mollusca). Additionally, we report for the first time Electroma vexillum from Israel, and Euthymella colzumensis, Joculator problematicus, Hemiliostraca clandestina, Pyrgulina nana, Pyrgulina microtuber, Turbonilla cangeyrani, Musculus aff. viridulus and Isognomon bicolor from Cyprus. We also report the second record of Fossarus sp. and of Cerithiopsis sp. cf. pulvis in the Mediterranean Sea, the first live collected specimens of Oscilla galilae from Cyprus and the northernmost record of Gari pallida in Israel (and the Mediterranean). Moreover, we report the earliest records of Rugalucina angela, Ervilia scaliola and Alveinus miliaceus in the Mediterranean Sea, backdating their first occurrence in the basin by 3, 5 and 7 years, respectively. We provide new data on the presence of Spondylus nicobaricus and Nudiscintilla aff. glabra in Israel. Finally, yet importantly, we use both morphological and molecular approaches to revise the systematics of the non-indigenous genus Isognomon in the Mediterranean Sea, showing that two species currently co-occur in the basin: the Caribbean I. bicolor, distributed in the central and eastern Mediterranean, and the Indo-Pacific I. aff. legumen, at present reported only from the eastern Mediterranean and whose identity requires a more in-depth taxonomic study. Our work shows the need of taxonomic expertise and investigation, the necessity to avoid the unfounded sense of confidence given by names in closed nomenclature when the NIS belong to taxa that have not enjoyed ample taxonomic work, and the necessity to continue collecting samples-rather than relying on visual censuses and bio-blitzes-to enable accurate detection of non-indigenous species.

Quantification of Allergic Crustacean Tropomyosin Using Shared Signature Peptides in Processed Foods with a Mass Spectrometry-Based Proteomic Strategy.

Crustacean shellfish are major allergens in East Asia. In the present study, a major allergic protein in crustaceans, tropomyosin, was detected accurately using multiple reaction monitoring mode-based mass spectrometry, with shared signature peptides identified through proteomic analysis. The peptides were deliberately screened through thermal stability and enzymatic digestion efficiency to improve the suitability and accuracy of the developed method. Finally, the proposed method demonstrated a linear range of 0.15 to 30 mgTM/kgfood (R2 > 0.99), with a limit of detection of 0.15 mgTM/kg food and a limit of quantification of 0.5mgTM/kgfood and successfully applied to commercially processed foods, such as potato chips, biscuits, surimi, and hot pot seasonings, which evidenced the applicability of proteomics-based methodology for food allergen analysis.

Preserved appendages in a Silurian binodicope: implications for the evolutionary history of ostracod crustaceans.

Ostracod crustaceans originated at least 500 Ma ago. Their tiny bivalved shells represent the most species-abundant fossil arthropods, and ostracods are omnipresent in a wide array of freshwater and marine environments today and in the past. Derima paparme gen. et sp. nov. from the Herefordshire Silurian Lagerstätte (~430 Ma) in the Welsh Borderland, UK, is one of only a handful of exceptionally preserved ostracods (with soft parts as well as the shell) known from the Palaeozoic. A male specimen provides the first evidence of the appendages of Binodicopina, a major group of Palaeozoic ostracods comprising some 135 Ordovician to Permian genera. The appendage morphology of D. paparme, but not its shell, indicates that binodicopes belong to Podocopa. The discovery that the soft-part morphology of binodicopes allies them with podocopes affirms that using the shell alone is an unreliable basis for classifying certain fossil ostracods, and knowledge of soft-part morphology is critical for the task. Current assignment of many fossil ostracods to higher taxa, and therefore the evolutionary history of the group, may require reconsideration.

A systematic review on microplastic contamination in marine Crustacea and Mollusca of Asia: Current scenario, concentration, characterization, polymeric risk assessment, and future Prospectives.

Microplastics (MPs) pollution has wreaked havoc on biodiversity and food safety globally. The false ingestion of MPs causes harmful effects on organisms, resulting in a decline in biodiversity. The present review comprehended the current knowledge of MP contamination in Crustacea and Mollusca from 75 peer-reviewed articles published in Asia between 2015 and 2023. A total of 79 species (27 Crustacea and 52 Mollusca) have been recorded to be contaminated with MPs. Out of the total 27 species of Crustacea, Metopograpsus quadridentatus (327.56 MPs/individual) and Balanus albicostatus (0.42 MPs/individual) showed the highest and lowest contamination, respectively. Out of the total 52 species of Mollusca, Dolabella auricularia (2325 MPs/individual) and Crassostrea gigas and Mytilus edulis (0.2 MPs/individual) showed the highest and lowest contamination, respectively. In terms of country-wise MP contamination, China has the highest number of contaminated species in both phylums among Asia. Findings of pollution indices revealed a very high risk of MP contamination in all the countries. Fiber was reported predominantly in both groups. Blue and black-colored MPs having <500 µm and <500 µm-1 mm size were found dominantly in Crustacea and Mollusca, respectively. Polypropylene was recorded as the dominant plastic polymer in both Crustacea and Mollusca. In essence, this review has provided a comprehensive insight into MP concentration in Crustacea and Mollusca of Asia, highlighting variations among species and geographic locations. This understanding is crucial for tackling urgent environmental challenges, safeguarding human health, and promoting global sustainability initiatives amid the escalating issue of plastic pollution. PRACTITIONER POINTS: Microplastic pollution has created havoc on biodiversity and food safety. A total of 27 and 52 species of crustaceans and Mollusca have been recorded to be contaminated with MPs. Metopograpsus quadridentate and Dolabella auricularia have shown higher MPs contamination. Polypropylene was recorded as the dominant plastic polymer in both crustacean and Mollusca. Findings of pollution indices revealed a very high risk of MP contamination in all the countries.

Holistic perilous index-based environmental appraisal of Metal(oid)s in the sole coral-bearing island of northeastern bay of Bengal.

This study aimed to evaluate the concentration, distribution, along with the environmental and human health impact of eight heavy metals-Pb, Cr, Cu, Cd, Zn, Mn, Ni, and As-on St. Martin's Island in the northeastern Bay of Bengal, and in doing so to help implement new legislations to protect the island. Focusing on the island's significance as a tourist destination, with seafood being a prominent dietary component, three sample types (sediment, seawater, and crustaceans) were selected for a comprehensive assessment, considering seasonal variations. Concentration of metals was observed to be lower than the established standards in sediment samples, but in seawater samples, Pb, Cr, Cd and Zn were higher than US-EPA values for natural marine water. The metals displayed a decreasing trend of Zn > Ni > Pb > Cu > Mn > As > Cd > Cr in crustacean samples for both seasons. Crustacean samples displayed higher metal concentrations in winter than in monsoon. Pb exceeded the maximum allowable limit for crustaceans with a concentration of about 3 and 4 mg kg-1 in monsoon and winter respectively; being more than 6-8 times the standard for Bangladesh which is only about 0.5 mg kg-1. Health indices displayed that although adults may suffer less from carcinogenic/non-carcinogenic health effects, the risks are far greater for children. For both age groups, As and Ni displayed possibilities of developing cancer. Principal Component Analysis (PCA)shed light on the sources of metals and showed that most of them were from anthropogenic sources. Overall, this study found that the quality of the environment of the island was better in comparison to previous studies made before the pandemic, and so, if the trend continues, it may lead to a better environment for the organisms around the island and help to keep the negative physiological impacts from the consumption of these organisms to a minimal.

A brief and updated introduction to the neuroendocrine system of crustaceans.

The neuroendocrine system of crustaceans is complex and regulates many processes, such as development, growth, reproduction, osmoregulation, behavior, and metabolism. Once stimulated, crustaceans' neuroendocrine tissues modulate the release of monoamines, ecdysteroids, and neuropeptides that can act as hormones or neurotransmitters. Over a few decades, research has unraveled some mechanisms governing these processes, substantially contributing to understanding crustacean physiology. More aspects of crustacean neuroendocrinology are being comprehended with molecular biology, transcriptome, and genomics analyses. Hence, these studies will also significantly enhance the ability to cultivate decapods, such as crabs and shrimps, used as human food sources. In this review, current knowledge on crustacean endocrinology is updated with new findings about crustacean hormones, focusing mainly on the main neuroendocrine organs and their hormones and the effects of these molecules regulating metabolism, growth, reproduction, and color adaptation. New evidence about vertebrate-type hormones found in crustaceans is included and discussed. Finally, this review may assist in understanding how the emerging chemicals of environmental concern can potentially impair and disrupt crustacean's endocrine functions and their physiology.

Exploring the underwater life in transitional environments: Benthic foraminifera, ostracods, and dinoflagellate cysts - Biotic trends and EcoQS assessment in the Mar Piccolo of Taranto (Ionian sea, southern Italy).

Coastal areas have historically thrived as centers of human activities due to their resources, economic opportunities, and natural allure. The rapid growth of coastal populations has however brought forth a multitude of challenges to tackle, with pollution emerging as a significant and far-reaching issue. Our study focuses on the Mar Piccolo of Taranto (Ionian Sea, Southern Italy), a lagoon-like coastal basin (separated in two sub-basins) that, since decades, has been heavily affected by human activities and aquaculture, leading to environmental deterioration. Although past studies have looked at environmental conditions in the Mar Piccolo from a chemical perspective, the biological component (e.g., biological indicators) has been mostly neglected. In this study, we firstly aim to examine the distribution and diversity of foraminifera, ostracods, and dinoflagellate cysts in December 2016 and compare our findings with data collected in December 2011. Foraminiferal and ostracod communities exhibit similar patterns in the two sampling campaigns, while the communities of encysted dinoflagellates show differences concerning both densities and diversity. Then, we evaluate the Ecological Quality Status (EcoQS) using ecological indices. While the indices in the inner basin appear to reflect an actual ecological degradation, they yield conflicting results in the outer basin. In the outer basin, indeed, the indices overestimate the EcoQS. This study highlights the potential of these indices for characterizing the EcoQS but emphasizes the need for improvements in their reliability. This research also contributes to a more holistic understanding of environmental condition in the Mar Piccolo and underscores the importance of integrating biological quality elements into ecosystem management and remediation strategies.

Exploring the purity of chitin from crustacean sources using deep eutectic solvents: A machine learning approach.

OBJECTIVE: Chitin a natural polymer is abundant in several sources such as shells of crustaceans, mollusks, insects, and fungi. Several possible attempts have been made to recover chitin because of its importance in biomedical applications in various forms such as hydrogel, nanoparticles, nanosheets, nanowires, etc. Among them, deep eutectic solvents have gained much consideration because of their eco-friendly and recyclable nature. However, several factors need to be addressed to obtain a pure form of chitin with a high yield. The development of an innovative system for the production of quality chitin is of prime importance and is still challenging. METHODS: The present study intended to develop a novel and robust approach to investigate chitin purity from various crustacean shell wastes using deep eutectic solvents. This investigation will assist in envisaging the important influencing parameters to obtain a pure form of chitin via a machine learning approach. Different machine learning algorithms have been proposed to model chitin purity by considering the enormous experimental dataset retrieved from previously conducted experiments. Several input variables have been selected to assess chitin purity as the output variable. RESULTS: The statistical criteria of the proposed model have been critically investigated and it was observed that the results indicate XGBoost has the maximum predictive accuracy of 0.95 compared with other selected models. The RMSE and MAE values were also minimal in the XGBoost model. In addition, it revealed better input variables to obtain pure chitin with minimal processing time. CONCLUSION: This study validates that machine learning paves the way for complex problems with substantial datasets and can be an inexpensive and time-saving model for analyzing chitin purity from crustacean shells.

Utilizing chitooligosaccharides from shrimp waste biodegradation via recombinant chitinase A: a promising approach for emulsifying hydrocarbon and bioremediation.

BACKGROUND: Hydrocarbon pollution stemming from petrochemical activities is a significant global environmental concern. Bioremediation, employing microbial chitinase-based bioproducts to detoxify or remove contaminants, presents an intriguing solution for addressing hydrocarbon pollution. Chitooligosaccharides, a product of chitin degradation by chitinase enzymes, emerge as key components in this process. Utilizing chitinaceous wastes as a cost-effective substrate, microbial chitinase can be harnessed to produce Chitooligosaccharides. This investigation explores two strategies to enhance chitinase productivity, firstly, statistical optimization by the Plackett Burman design approach to  evaluating the influence of individual physical and chemical parameters on chitinase production, Followed by  response surface methodology (RSM) which delvs  into the interactions among these factors to optimize chitinase production. Second, to further boost chitinase production, we employed heterologous expression of the chitinase-encoding gene in E. coli BL21(DE3) using a suitable vector. Enhancing chitinase activity not only boosts productivity but also augments the production of Chitooligosaccharides, which are found to be used as emulsifiers. RESULTS: In this study, we focused on optimizing the production of chitinase A from S. marcescens using the Plackett Burman design and response surface methods. This approach led to achieving a maximum activity of 78.65 U/mL. Subsequently, we cloned and expressed the gene responsible for chitinase A in E. coli BL21(DE3). The gene sequence, named SmChiA, spans 1692 base pairs, encoding 563 amino acids with a molecular weight of approximately 58 kDa. This sequence has been deposited in the NCBI GenBank under the accession number "OR643436". The purified recombinant chitinase exhibited a remarkable activity of 228.085 U/mL, with optimal conditions at a pH of 5.5 and a temperature of 65 °C. This activity was 2.9 times higher than that of the optimized enzyme. We then employed the recombinant chitinase A to effectively hydrolyze shrimp waste, yielding chitooligosaccharides (COS) at a rate of 33% of the substrate. The structure of the COS was confirmed through NMR and mass spectrometry analyses. Moreover, the COS demonstrated its utility by forming stable emulsions with various hydrocarbons. Its emulsification index remained stable across a wide range of salinity, pH, and temperature conditions. We further observed that the COS facilitated the recovery of motor oil, burned motor oil, and aniline from polluted sand. Gravimetric assessment of residual hydrocarbons showed a correlation with FTIR analyses, indicating the efficacy of COS in remediation efforts. CONCLUSIONS: The recombinant chitinase holds significant promise for the biological conversion of chitinaceous wastes into chitooligosaccharides (COS), which proved its potential in bioremediation efforts targeting hydrocarbon-contaminated sand.

Similar enzymatic functions in distinct bioluminescence systems: evolutionary recruitment of sulfotransferases in ostracod light organs.

Genes from ancient families are sometimes involved in the convergent evolutionary origins of similar traits, even across vast phylogenetic distances. Sulfotransferases are an ancient family of enzymes that transfer sulfate from a donor to a wide variety of substrates, including probable roles in some bioluminescence systems. Here, we demonstrate multiple sulfotransferases, highly expressed in light organs of the bioluminescent ostracod Vargula tsujii, transfer sulfate in vitro to the luciferin substrate, vargulin. We find luciferin sulfotransferases (LSTs) of ostracods are not orthologous to known LSTs of fireflies or sea pansies; animals with distinct and convergently evolved bioluminescence systems compared to ostracods. Therefore, distantly related sulfotransferases were independently recruited at least three times, leading to parallel evolution of luciferin metabolism in three highly diverged organisms. Reuse of homologous genes is surprising in these bioluminescence systems because the other components, including luciferins and luciferases, are completely distinct. Whether convergently evolved traits incorporate ancient genes with similar functions or instead use distinct, often newer, genes may be constrained by how many genetic solutions exist for a particular function. When fewer solutions exist, as in genetic sulfation of small molecules, evolution may be more constrained to use the same genes time and again.

Novel molecular resources for single-specimen barcoding of enigmatic crustacean y-larvae.

Despite discovery more than 100years ago and documented global occurrence from shallow waters to the deep sea, the life cycle of the enigmatic crustacean y-larvae isincompletely understood and adult forms remain unknown. To date, only 2 of the 17 formally described species, all based on larval stages, have been investigated using an integrative taxonomic approach. This approach provided descriptions of the morphology of the naupliar and cyprid stages, and made use of exuvial voucher material and DNA barcodes. To improve our knowledge about the evolutionary history and ecological importance of y-larvae, we developed a novel protocol that maximises the amount of morpho-ecological and molecular data that can be harvested from single larval specimens. This includes single-specimen DNA barcoding and daily imaging of y-nauplii reared in culture dishes, mounting of the last naupliar exuviae on a slide as a reference voucher, live imaging of the y-cyprid instar that follows, and fixation, DNA extraction, amplification and sequencing of the y-cyprid specimen. Through development and testing of a suite of new primers for both nuclear and mitochondrial protein-coding and ribosomal genes, we showcase how new sequence data can be used to estimate the phylogeny of Facetotecta. We expect that our novel procedure will help to unravel the complex systematics of y-larvae and show how these fascinating larval forms have evolved. Moreover, we posit that our protocols should work on larval specimens from a diverse array of moulting marine invertebrate taxa.

Behavior and morphology combine to influence energy dissipation in mantis shrimp (Stomatopoda).

Animals deliver and withstand physical impacts in diverse behavioral contexts, from competing rams clashing their antlers together to archerfish impacting prey with jets of water. Though the ability of animals to withstand impact has generally been studied by focusing on morphology, behaviors may also influence impact resistance. Mantis shrimp exchange high-force strikes on each other's coiled, armored telsons (tailplates) during contests over territory. Prior work has shown that telson morphology has high impact resistance. I hypothesized that the behavior of coiling the telson also contributes to impact energy dissipation. By measuring impact dynamics from high-speed videos of strikes exchanged during contests between freely moving animals, I found that approximately 20% more impact energy was dissipated by the telson as compared with findings from a prior study that focused solely on morphology. This increase is likely due to behavior: because the telson is lifted off the substrate, the entire body flexes after contact, dissipating more energy than exoskeletal morphology does on its own. While variation in the degree of telson coil did not affect energy dissipation, proportionally more energy was dissipated from higher velocity strikes and from strikes from more massive appendages. Overall, these findings show that analysis of both behavior and morphology is crucial to understanding impact resistance, and suggest future research on the evolution of structure and function under the selective pressure of biological impacts.

Complexity of trophic relationships between Gammarus aequicauda (Amphipoda) and Eucypris mareotica (Ostracoda) in a hypersaline lake.

In the hypersaline lakes of Crimea, only 5-7 species of animals are common including Gammarus aequicauda (Amphipoda) and Eucypris mareotica (Ostracoda). Two experiments were carried out to characterize the trophic interactions between these species. In one, G. aequicauda were used freshly caught from the lake, and in the other, after they were starved for 2.5 days in the laboratory. The experimental options were one male or female G. aequicauda and either 10, 20, or 30 ostracods. The gammarids actively fed on the ostracods, and significant differences were between females and males. The feeding intensity of males was higher than that of females. However, ostracods are not passive prey, they can actively attack their predator and are capable of causing them harm. Ostracods attacked a Gammarus only if it had captured one of the ostracods. Sex differences in G. aequicauda were also evident in the reaction to the group's aggressive behavior of ostracods. Interactions between Ostracoda and Gammarids cannot be considered unidirectional; they both may be prey or predators depending on the situation.

Biological and functional responses of the benthic surf zone community to different beach types.

In this study, we analyzed the biological descriptors and functional traits of the benthic community inhabiting the water/bottom layer in the surf zones of three sandy beaches: a tide-dominated flat, and two intermediate beaches, from tide-modified to wave-dominated. Samples were collected seasonally in the inner surf zone by hand-towing a benthic sledge equipped with two nets, one above the other, across transects parallel to the shore, capturing the benthic community in two levels, close to the seafloor. A total of 116 species were collected, with a total of 327,678 specimens. Arthropods were 99.63% of all individuals caught across the three beaches, mainly represented by peracarid crustaceans. An important species turnover was detected along the shore, with a significant change in community composition. The biological descriptors and some functional traits vary among beaches: the total density, the density of individuals of small (5-10 mm length) and very small sizes (<5 mm length), the density of larval forms, and the presence of colonial species were higher in the tide-dominated flat (sometimes also in the tide-modified beach). More arthropods and more mobile individuals were found in those beaches, while mollusks and sedentary individuals were found in high number in the wave-dominated beach. Stratification was present across the three studied beaches, with higher densities in the near-bottom layer. In the tide-dominated beach, there was also a higher richness in this layer, with a nested community between levels. In the wave-dominated beach, similar richness was registered between levels, with a different community composition (and some differences in functional traits), indicating that some species can maintain their position close to the bottom despite the turbulent conditions experienced on this beach. Differences in wave conditions among beach types could be an important factor driving the biological descriptors and functional traits of the benthic community in surf zone ecosystems. Therefore, acknowledging their role is crucial in deciphering global patterns in surf zone biodiversity.

Interactive effects between water temperature, microparticle compositions, and fiber types on the marine keystone species Americamysis bahia.

Recently, there has been an increasing emphasis on examining the ecotoxicological effects of anthropogenic microparticles (MPs), especially microplastic particles, and related issues. Nevertheless, a notable deficiency exists in our understanding of the consequences on marine organisms, specifically in relation to microfibers and the combined influence of MPs and temperature. In this investigation, mysid shrimp (Americamysis bahia), an important species and prey item in estuarine and marine food webs, were subjected to four separate experimental trials involving fibers (cotton, nylon, polyester, hemp; 3 particles/ml; approximately 200 µm in length) or fragments (low-density Polyethylene: LDPE, polylactic acid: PLA, and their leachates; 5, 50, 200, 500 particles/ml; 1-20 µm). To consider the effects in the context of climate change, three different temperatures (22, 25, and 28 °C) were examined. Organismal growth and swimming behavior were measured following exposure to fragments and microfibers, and reactive oxygen species and particle uptake were investigated after microfiber exposure. To simulate the physical characteristics of MP exposure, such as microfibers obstructing the gills, we also assessed the post-fiber-exposure swimming behavior in an oxygen-depleted environment. Data revealed negligible fragment, but fiber exposure effects on growth. PLA leachate triggered higher activity at 25 °C and 28 °C; LDPE exposures led to decreased activity at 28 °C. Cotton exposures led to fewer behavioral differences compared to controls than other fiber types. The exposure to hemp fibers resulted in significant ROS increases at 28 °C. Microfibers were predominantly located within the gastric and upper gastrointestinal tract, suggesting extended periods of residence and the potential for obstructive phenomena over the longer term. The combination of increasing water temperatures, microplastic influx, and oxidative stress has the potential to pose risks to all components of marine and aquatic food webs.

A novel dual-channel cassava starch/polyvinyl alcohol-based film for visual monitoring of shrimp freshness.

In this study, the polyvinylpyrrolidone-alizarin nanoparticles (PVP-AZ NPs) with favorable water dispersion and the carbon quantum dots (RQDs) with aggregate induced emission effect were synthesized to construct an eco-friendly film for food freshness monitoring. The introduction of PVP-AZ NPs and RQDs enhanced the network structure and thermal stability of the cassava starch/polyvinyl alcohol film, and reduced its crystallinity and light transmittance via non-covalent binding with the film-forming matrix. The developed film exhibited visually recognizable colorimetric and fluorescent responses to ammonia at 0.025-25 mg/mL, and it can be reused at least 6 times. Practical application experiment proved that the film, as an indicator label, can achieve accurate, real-time, and visual dynamic monitoring of the freshness of shrimp stored at 25 °C, 4 °C, and - 20 °C under daylight (orange yellow to purple) and UV light (red to blue). The integration of multivariate detection technology can eliminate the interference of external factors by self-correction to improve sensitivity and reliability, which provides a reference for the development of other food quality and safety monitoring platforms.

Dissemination, virulence characteristic, antibiotic resistance determinants of emerging linezolid and vancomycin-resistant Enterococcus spp. in fish and crustacean.

Enterococci are emerging nosocomial pathogens. Their widespread distribution causes them to be food contaminants. Furthermore, Enterococci can colonize various ecological niches and diffuse into the food chain via contaminated animals and foods because of their remarkable tolerance to unfavorable environmental circumstances. Due to their potential dissemination to humans, antimicrobial-resistant Enterococci in fish are a worldwide health issue. This study characterized AMR, ARGs, VAGs, gelatinase activity, and biofilm formation in Enterococcus spp. recovered from fish and seafood and evaluated potential correlations. 54 Enterococcus spp. strains(32.73 %)were isolated from 165 samples (75 Oreochromis niloticus, 30 Argyrosomus regius, and 60 Shrimp), comprising 30 Enterococcus faecalis (55.6 %) and 24 Enterococcus faecium (44.4 %) with total 32.73 % (54/165), The maximum prevalence rate of Enterococcus spp. was observed in Nile tilapia (34/54; 63 %), followed by shrimp (14/54; 25.9 %) and Argyrosomus regius (6/54; 11.1 %). The maximum prevalence rate of E. faecalis was observed in Nile tilapia (22/30; 73.3 %), followed by shrimp (8/30; 26.7 %) with significant differences. The prevalence rate of E. faecium was observed in Nile tilapia (12/24; 50 %), followed by shrimp (6/24,25 %). E. faecium is only isolated from Argyrosomus regius (6/24,25 %). Isolates exhibited high resistance against both tetracycline (90.7 %) and erythromycin(88.9 %), followed by gentamycin (77.8 %), ciprofloxacin (74.1 %), levofloxacin (72.2 %), penicillin (44.4 %), vancomycin (37 %), and linezolid (20.4 %). 50 strains (92.6 %) exhibited resistance to more than two antibiotics, 5 strains (10 %) were XDR, and the remaining 45 strains (90 %) were classified as MDR. 92.6 % of the isolates had MARindices >0.2, indicating they originated in settings with a high risk of contamination. Additionally, ten ARGs were identified, with tet(M) 92.6 %, followed by erm(B) (88.9 %), aac(6')-Ie-aph(2″)-Ia(77.8 %), tet(K) (75.9 %), gyrA (74.1 %), blaZ (48.1 %), vanA (37 %), vanB (31.5 %), optrA (20.4 %), and catA(3.7 %). Biofilm formation and gelatinase activity were observed in 85.2 %, and 61.1 % of the isolates, respectively. A total of 11 VAGs were detected, with gelE as the most prevalent (83.3 %) followed by agg(79.6 %), pil (74.1 %), both sprE and asa1 (72.2 %), hyl (70.4 %), eps(68.5 %), EF3314 (57.4 %), ace (50 %), and cylA (35.2 %) with no detection of cylB. In conclusion, the emergence of linezolid-resistant -vancomycin-resistant enterococci recovered from Egyptian fish and shrimp, suggests that fish and seafood might participate a fundamental part in the emergence of antimicrobial resistance among humans.