In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detec...In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detection of Vibrio parahaemolyticus.The nanozyme integrated magnetic separation,peroxidase-like catalytic activity,and specific target recognition through an aptamer-based strategy.Upon binding to V.parahaemolyticus,the catalytic oxidation of tetra-aminophenylethylene(TPE-4A)by the nanozyme was selectively inhibited,resulting in distinct colorimetric and fluorescent signals that significantly enhanced the detection accuracy and reliability.The proposed method exhibited high sensitivity,with limits of detection(LOD)of 21 and 7 CFU/mL for the colorimetric and fluorescent assays,respectively.The performance of this method was validated using real seafood samples,including Penaeus vannamei,Mytilus coruscus,and Crassostrea gigas,which showed high recovery rates(101.11%-107.30%)and excellent reproducibility.The system also demonstrated strong specificity and accuracy under various conditions,confirming its robustness and practical applicability.Collectively,this innovative platform presents a promising solution for the rapid,versatile,and sensitive detection of V.parahaemolyticus in seafood,with considerable potential to advance food safety diagnosis and on-site monitoring.展开更多
Microplastics,resulting from human activities,are widespread environmental contaminants that threaten both ecosystems and human health.These particles,less than 5 mm in size,are found in air,soil,and water,originating...Microplastics,resulting from human activities,are widespread environmental contaminants that threaten both ecosystems and human health.These particles,less than 5 mm in size,are found in air,soil,and water,originating from industrial waste and everyday plastic products.They come in various shapes,sizes,and colors,with primary and secondary microplastics formed through degradation processes.Microplastics have entered the food chain,affecting all trophic levels,with detrimental effects on organisms such as plankton,fish,and corals.Research on microplastics is hindered by methodological biases and sampling inconsistencies,which impact the reliability and comparability of data,as different techniques often yield varying results.Current degradation methods,including bioremediation and filtration,show potential but remain limited.Detecting microplastics is challenging due to their small size,though advanced techniques like morphological and analytical analyses,particularly in fish guts,aid detection.Targeted studies on microplastic levels in aquatic species are crucial,and the development of biodegradable alternatives is essential to mitigate their long-term environmental impact.展开更多
The dinoflagellates Alexandrium pacificum and Prorocentrum donghaiense are two well-known harmful algal blooms(HABs)-forming species,both were usually found in the same sea areas in form of HABs in China.To date,there...The dinoflagellates Alexandrium pacificum and Prorocentrum donghaiense are two well-known harmful algal blooms(HABs)-forming species,both were usually found in the same sea areas in form of HABs in China.To date,there is no mechanistic model that can fully explain the occurrence of P.donghaiense blooms with A.pacificum.We found that different strains of P.donghaiense had different intrinsic growth rates of 0.107-0.215/d,and these strains exhibited different responses to the allelopathic action from A.pacificum.Some strains of P.donghaiense could grow well despite some degrees of inhibition in a short period,suggesting the two algal species P.donghaiense and A.pacificum could coexist,even if A.pacificum was allelopathic.Our findings may advance the understanding of phenotypes in P.donghaiense and provide a potential mechanism involved in the coexistence of P.donghaiense and A.pacificum in the same area.展开更多
The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level c...The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.展开更多
Withania somnifera(L.)Dunal(WS),or Ashwagandha,is used clinically against arthritis,anxiety and insomnia etc,however,its potential in aquafeeds is largely unexplored.We investigated the stress-alleviation and hepatopr...Withania somnifera(L.)Dunal(WS),or Ashwagandha,is used clinically against arthritis,anxiety and insomnia etc,however,its potential in aquafeeds is largely unexplored.We investigated the stress-alleviation and hepatoprotective mechanisms of dietary WS supplementation in adult female darkbarbel catfish.Fish were fed with WS dietary for 5 weeks,subjected to a physical stressor(saline injection),and sampled.Brain were processed for RNA-seq to identify differentially expressed genes(DEGs)linked to stress;serum were assayed for stress-and immune-related biochemical markers;livers were examined for lipid content(Oil Red O staining)and proliferation(PCNA immunos-taining).Network pharmacology were employed to construct a"compound-target"net-work:The bioactive compounds of WS were retrieved from ChEBI and PCIDB,probable targets predicted via Swiss Target Prediction,and the“WS-ingredient-target”regulatory network was constructed using Cytoscape;key ligand-protein interactions were validated by molecular docking.Findings were replicated in juvenile fish and in SG3 cells challenged with Withanolide A.Physical stress evoked 1451 DEGs in control brains,whereas WS-supplemented reduced this to 397,indicating marked mitigation of the oxid-ative-and immune-stress response.Network pharmacology and molecular docking pre-dicted that 13 bioactive compounds in WS,especially Withanolide A and Withanolide J,can interact with targets such as MAPK8,CRHR1,NR3C2,and IARS1,being associated with stress and liver function regulation respectively.Moreover,it was proved that Withanolide A could significantly modulate stress response in juveniles and enhanced pro-liferation potency of SG3 cells.Intriguingly,in theadult female darkbarbel catfish,dietary WS lowered serum cortisol,glucose,ROS,TNF-α,and IL-6(P<0.05),up-regulated hepatocyte PCNA expression,and allievated stress-induced liver injury.These findings provide novel insights and vital basis for elucidating the mechanisms whereby herbs,including WS act in stress-relief and hepatoprotection in darkbarbel catfish.And provide a framework for advancing traditional Chinese medicine(TCM)applications in aquaculture.展开更多
Perfluorooctanoic acid(PFOA),a novel contaminant,is extensively found in aquatic environments.However,the capability of the denitrifying phosphorus removal process to treat PFOA-containing wastewater,as well as its re...Perfluorooctanoic acid(PFOA),a novel contaminant,is extensively found in aquatic environments.However,the capability of the denitrifying phosphorus removal process to treat PFOA-containing wastewater,as well as its response mechanisms,are unclear.This study used batch experiments to assess the short-term impact of PFOA on denitrifying phosphorus removal systems.During a single cycle,the addition of PFOA predominantly enhanced phosphate removal in the system mainly by the anaerobic phosphorus release pathway,but had no substantial effect on nitrogen removal.COD removal efficiency has a substantial positive correlation with C6-HSL and C8-HSL concentrations.As the PFOA concentration increased,the ROS concentration and enzyme activity also increased,while the PN/PS ratio decreased,causing the sludge to become looser.At the beginning of the second cycle,the impact of PFOA on phosphorus removal efficiency shifted from promotion to inhibition.These findings shed fresh light on the influence of PFOA on the denitrifying phosphorus removal mechanism,potentially furthering its use in the treatment of fluoride-containing wastewater.展开更多
The functional diversity index of a phytoplankton body has gradually become a new mean of measuring and research.To explore the response of phytoplankton taxonomy and the functional diversity index to interannual envi...The functional diversity index of a phytoplankton body has gradually become a new mean of measuring and research.To explore the response of phytoplankton taxonomy and the functional diversity index to interannual environmental changes,a survey on the structure of the phytoplankton community and water physicochemical characteristics of the water was carried out at 28 sampling points in the Harbin section of the Songhua River for three consecutive years in every May from 2021 to 2023.The taxonomy diversity index and the functional diversity index were calculated.Firstly,The relationship between the structure of the characteristics of the community and environmental factors was explored;secondly,we reveal the responses of taxonomic and functional diversity indices to different habitats between years;finally,we explore the main environmental factors that control the taxonomic and functional diversity indices of phytoplankton.Results show that,initially,environmental factors in water changes caused by different water levels between years affected the composition of phytoplankton communities.Subsequently,by comparing the taxonomic diversity index and the functional diversity index on a time scale,we found that the taxonomic diversity index was more responsive to environmental changes.Ultimately,the main environmental factors on the phytoplankton taxonomic diversity index were dissolved oxygen,Taxonomic diversity index,and specific conductivity,and the main environmental factors that affected the functional diversity index were dissolved oxygen,turbidity,and water temperature.This study reveals the important role of the taxonomic diversity index in river water quality evaluation,obtained new information on the relative precision of the taxonomic diversity index and the functional diversity index in the evaluation of ecological health of the water,and provided a reliable tool for monitoring river water quality based on aquatic organisms.展开更多
The East China Sea(ECS)off the Coast of Zhoushan Archipelago,Zhejiang(ECS-CZA)is home to abundant fishery resources and an important spawning,feeding,and nursing ground for a variety of fish species.Due to long-term o...The East China Sea(ECS)off the Coast of Zhoushan Archipelago,Zhejiang(ECS-CZA)is home to abundant fishery resources and an important spawning,feeding,and nursing ground for a variety of fish species.Due to long-term overfishing,the ichthyoplankton structure has been dramatically altered.Understanding the species composition and distribution of fish eggs and larvae is one of the most essential tasks to accurately regulate fishery resources and formulate effective management policies;however,little is known about the ichthyoplankton in this region.In this study,an integrated strategy of morphology identification(MI)and mitochondrial COI DNA barcoding was used to identify species of fish eggs and larvae collected from the ECSCZA.MI revealed 15 fish egg species belonging to 12 families and 12 fish larva species belonging to 12 families;in contrast,DNA barcoding altogether identified 30 species,including 18 fish egg species and 13 fish larva species.One species was shared between the egg and larva samples.Our study offers useful tools and critical scientific information for further understanding the diversity,distribution,and conservation management of various ichthyoplankton species in the marine environment.展开更多
[Objectives] To analyze the function of cobQ gene from Vibrio alginolyticus strain HY9901,and to provide a reference for exploring the possible mechanism of cobQ gene from V.alginolyticus.[Methods] A pair of primers w...[Objectives] To analyze the function of cobQ gene from Vibrio alginolyticus strain HY9901,and to provide a reference for exploring the possible mechanism of cobQ gene from V.alginolyticus.[Methods] A pair of primers were designed based on the sequence of the V.alginolyticus cobQ gene and used to amplify the full-length gene by PCR.[Results] The PCR amplification results indicated that the cobQ gene has a full length of 780 bp,encoding 259 amino acid residues.The deduced amino acid sequence predicts a molecular weight of approximately 28.83 kD and an isoelectric point of 9.21.Sequence analysis revealed no N-terminal signal peptide cleavage site,suggesting the absence of both a signal peptide and transmembrane regions in this protein.The amino acid sequence contains 2 N-terminal myristoylation sites,1 N-glycosylation site,1 glycosaminoglycan attachment site,4 microbody C-terminal targeting signal sites,3 casein kinase II phosphorylation sites,and 4 protein kinase C phosphorylation sites.Subcellular localization prediction showed that the CobQ protein is primarily localized in the cytoplasm(65.2%probability).Homology analysis demonstrated that the amino acid sequence of the cobQ gene from V.alginolyticus shares up to 99%homology with other Vibrio species,clustering within the same subclade as Vibrio parahaemolyticus,indicating close phylogenetic relationships.Secondary structure prediction revealed proportions ofα-helices,random coils,and extended strands as 44.40%,36.68%,and 18.92%,respectively.The tertiary structure model exhibited 87.62%similarity to the template A0A165XBE1.1.[Conclusions] In this study,the V.alginolyticus cobq gene was successfully cloned and its sequence was analyzed by bioinformatics.It is expected to lay a foundation for the subsequent study of the regulatory mechanism of its protein on the virulence of V.alginolyticus.展开更多
Polycyclic aromatic hydrocarbons(PAHs)are of great concern because they threaten pri-mary productivity,but their specific effects on ecosystem functioning are scarce,hindering a comprehensive understanding of their ec...Polycyclic aromatic hydrocarbons(PAHs)are of great concern because they threaten pri-mary productivity,but their specific effects on ecosystem functioning are scarce,hindering a comprehensive understanding of their ecological risks,especially in eutrophicwaters.The present study was conducted by adding PAHs to four marine phytoplankton species and showed that naphthalene(Nap)and phenanthrene(Phe)induced both stimulatory and in-hibitory effects(>50%)on urea and NO_(3)−uptake by phytoplankton species.In addition,the apparent stimulative effects(>50%)for NH_(4)^(+)were also observed.Overall,38.9%of the sam-ples exhibited stimulation effects after 24 h exposure,which increased to 61.1%after 96 h exposure.This suggested the existence of a lag period,during which a tolerant cell popula-tion could adapt to PAHs.Significant positive correlations(P<0.01)between low and high concentrations of PAH individuals demonstrated that the mode of action for both pollutants on nitrogen uptake by phytoplankton was the same.Species-specific responses were also observed,with 19.0%of Thalassiosira sp.and 24.0%of Tetraselmis sp.exhibited inhibition effects greater than 50%,while 40.9%of Karlodinium veneficum and 27.3%of Rhodomonas salina demonstrated stimulation effects exceeding 50%,providing a unique perspective for exploring the harmful algal bloom of the mixotrophic K.veneficum,in addition to the original consideration of nutrients.The internal mechanisms may lie in differences in energy consumption between N-forms,exposure time and chemical concentrations,aswell as mor-phological characteristics and biochemical structures of the species,which require further investigation.展开更多
Designing high-performance electrocatalysts is one of the key challenges in the development of microbial electrochemical hydrogen production.Transition metal-based(TM-based)electrocatalysts are introduced as an astoni...Designing high-performance electrocatalysts is one of the key challenges in the development of microbial electrochemical hydrogen production.Transition metal-based(TM-based)electrocatalysts are introduced as an astonishing alternative for future catalysts by addressing several disadvantages,like the high cost and low performance of noble metal and metal-free electrocatalysts,respectively.In this critical review,a comprehensive analysis of the major development of all families of TMbased catalysts from the beginning development of microbial electrolysis cells in the last 15 years is presented.Importantly,pivotal design parameters such as selecting efficient synthesis methods based on the type of material,main criteria during each synthesizing method,and the pros and cons of various procedures are highlighted and compared.Moreover,procedures for tuning and tailoring the structures,advanced strategies to promote active sites,and the potential for implementing novel unexplored TM-based hybrid structures suggested.Furthermore,consideration for large-scale application of TM-based catalysts for future mass production,including life cycle assessment,cost assessment,economic analysis,and recently pilot-scale studies were highlighted.Of great importance,the potential of utilizing artificial intelligence and advanced computational methods such as active learning,microkinetic modeling,and physics-informed machine learning in designing high-performance electrodes in successful practices was elucidated.Finally,a conceptual framework for future studies and remaining challenges on different aspects of TM-based electrocatalysts in microbial electrolysis cells is proposed.展开更多
[Objectives]This study was conducted to investigate the functional characteristics of the trxB gene in Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the trxB gene sequence of V.alginol...[Objectives]This study was conducted to investigate the functional characteristics of the trxB gene in Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the trxB gene sequence of V.alginolyticus for PCR cloning of its full-length sequence.Systematic bioinformatics analyses were conducted to predict the physicochemical properties,secondary structure,and tertiary structure of the encoded protein.[Results]The trxB gene is 960 bp in length,encoding 319 amino acid residues.The deduced protein has a predicted molecular weight of 34.32 kDa and an isoelectric point(pI)of 4.77.Analysis of the amino acid sequence revealed a distinct signal peptide cleavage site at the N-terminus,with no transmembrane domains.The functional sites are as follows:1 N-glycosylation site,1 cAMP-and cGMP-dependent protein kinase phosphorylation site,4 protein kinase C phosphorylation sites,7 casein kinase II phosphorylation sites,1 tyrosine kinase phosphorylation site,11 N-myristoylation sites,1 prenyl group binding site,3 microbody C-terminal targeting signal sites,and 1 xanthine nucleotide-disulfide oxidoreductase class II active site.Subcellular localization prediction indicated the highest probability(44.4%)for endoplasmic reticulum localization.The TrxB amino acid sequence of V.alginolyticus shares 97.2%-98.4%homology with other Vibrio species,and they were clustered within the same subgroup.Secondary structure prediction showed proportions of random coils(31.97%),alpha-helices(31.66%),extended strands(25.08%),and beta turns(11.29%).The tertiary structure model exhibited 88.68%similarity to template 5vt3.1.A.[Conclusions]This study elucidated the characterization of the TrxB protein in V.alginolyticus,laying a theoretical foundation for the development of outer membrane protein subunit vaccines against this pathogen.展开更多
[Objectives]To develop a pair of specific primers for the PCR amplification of the full-length relA gene from Vibrio alginolyticus strain HY9901,as well as to conduct bioinformatics analysis.[Methods]The relA gene was...[Objectives]To develop a pair of specific primers for the PCR amplification of the full-length relA gene from Vibrio alginolyticus strain HY9901,as well as to conduct bioinformatics analysis.[Methods]The relA gene was amplified through PCR,and the resulting gene sequence was subsequently analyzed using bioinformatics tools,including amino acid sequence prediction,functional site analysis,subcellular localization prediction,and homology comparison.[Results]The relA gene had a total length of 2220 bp and encoded 739 amino acid residues.The molecular weight was approximately 84.1261 kDa,and its isoelectric point was 5.95.The protein lacked a signal peptide and transmembrane regions,while exhibiting multiple phosphorylation sites.Predictions regarding its subcellular localization suggested that it was predominantly situated in the cytoplasm.The amino acid sequence demonstrated a homology of 97%to 99%with other species within the genus Vibrio,and it clustered within the same subfamily as V.antiquarius and V.diabolicus.In the prediction of secondary structure,the proportions ofα-helix,extended strand,random coil,andβ-sheet were 54.13%,12.04%,28.15%and 5.68%,respectively.The similarity between the tertiary structure model and template 5kpw.1.w was 66%.[Conclusions]In this study,the relA gene of V.alginolyticus strain HY9901 has been successfully amplified and analyzed.The structural characteristics and potential functions of the encoded protein have been elucidated,thereby providing foundational data for understanding the role of this gene in V.alginolyticus.展开更多
Current evidence supports high temperature-induced masculinization as the primary temperature-dependent sex determination(TSD)pattern in fish.To date,no study has reported bidirectional TSD in a fish species,in which ...Current evidence supports high temperature-induced masculinization as the primary temperature-dependent sex determination(TSD)pattern in fish.To date,no study has reported bidirectional TSD in a fish species,in which low temperature induces masculinization while high temperature induces feminization.In this study,Onychostoma macrolepis exhibited a distinctive bidirectional TSD pattern,with a balanced 1:1 sex ratio at24°C(moderate temperature),over 80%female development at 28°C(high temperature),and approximately 75%male development at 20°C(low temperature).Transcriptomic analyses revealed kdm6bb and calcium channel genes as key regulators of TSD among the differentially expressed genes between high and low temperature groups.Consistently,administration of calcium influx and Kdm6bb inhibitors effectively blocked high temperature-induced feminization and low temperature-induced masculinization,respectively.These findings indicate that temperature perception in O.macrolepis is mediated through calcium signaling,which regulates the expression of the epigenetic modifier kdm6bb and consequently modulates sex determination.Unexpectedly,canonical male pathway genes such as dmrt1 and gsdf showed higher expression in the high temperature group than in the low temperature group at 50days after fertilization(daf).Administration of aromatase inhibitors failed to induce sex reversal at either temperature,whereas extremely low concentrations of testosterone/methyltestosterone(T/MT)and 17β-estradiol(E2)successfully induced sex reversal under high and low temperature conditions,respectively.These results suggest that downstream regulatory pathways controlling sexual differentiation in O.macrolepis are distinct from conventional TSD models.The discovery of this bidirectional mechanism establishes O.macrolepis as an exceptional model for elucidating the molecular and physiological bases of temperature-driven sex determination and underscores the ecological risks of global warming for aquatic vertebrates.展开更多
Microplastics(MPs),particularly polyvinyl chloride microplastics(PVC MPs)have become a notable environmental pollutant that affect various marine organisms such as Pinctada fucata martensii.As filter feeders,these biv...Microplastics(MPs),particularly polyvinyl chloride microplastics(PVC MPs)have become a notable environmental pollutant that affect various marine organisms such as Pinctada fucata martensii.As filter feeders,these bivalves consume significant volumes of water containing MPs,leading to contact with and ingestion of MPs.Moreover,given the ecological and economic importance of P.f.martensii in artificial pearl production,investigating the effects of PVC MPs exposure is crucial.This study aimed to investigate the effects of PVC MPs exposure on nucleus retention,pearl formation,oxidative stress by examining superoxide dismutase(SOD)activity,catalase(CAT)activity,lipid peroxidation(LPO),and total antioxidant capacity(TAOC)of P.f.martensii,while also exploring transcriptomic changes at different concentrations and exposure time points,including a recovery period.The pearl oysters were exposed to PVC MPs at concentrations of 1-,2.5-,and 5-mg PVC MPs/L for 10 d followed by 6 d of recovery.After 1-,4-,10-d of exposure,and additional 6 d of recovery,samples were taken and analyzed.Findings revealed that only prolonged exposure(10 d)to PVC MPs affected SOD activity,while CAT activity,LPO,and TAOC remained unaffected throughout the experiment.Notably,SOD activity was restored during the 6-d recovery phase.Transcriptome analysis highlighted significant gene alterations linked to various pathways,affecting cellular processes,environmental information processing,genetic information processing,metabolism,and organismal systems,with an increase in pathway-related genes during recovery,implying a potential role of PVC MPs as gene inhibitors.This study provided insights into the effects of PVC MPs on P.f.martensii,shedding light on pearl retention,oxidative systems,and molecular pathways influenced by PVC MPs.Additionally,it contributed novel information on potential MPs exposure biomarkers,particularly relevant to marine organisms like P.f.martensii.展开更多
In this study,we aimed to isolate potential Bacillus strains from the digestive tract of Nile tilapia(Oreochromis niloticus).Through morphological,biochemical,16S rDNA sequencing,and evolutionary relationship assessme...In this study,we aimed to isolate potential Bacillus strains from the digestive tract of Nile tilapia(Oreochromis niloticus).Through morphological,biochemical,16S rDNA sequencing,and evolutionary relationship assessments,we identified the isolated species as Bacillus amyloliquefaciens AV5(OR647358),Bacillus subtilis AV7(LC781790),and Bacillus velezensis AV50(OR647359),designated as AV5,AV7,and AV50 strains,respectively.We evaluated their probiotic potential,including tolerance to high bile salt concentrations,low pH levels,and high temperatures,as well as their adhesion abilities(auto-aggregation and cell-surface hydrophobicity),antimicrobial activity,biosafety,compatibility,hemolytic activity,and antibiotic susceptibility.AV5,AV7,and AV50 strains exhibitedγ-hemolytic activity and resistance to low pH(1)and high bile salt concentrations(0.5%).They demonstrated higher viability after exposure to elevated temperatures(80℃,90℃,and 100℃)and increased cell surface hydrophobicity and autoaggregation.These strains showed positive compatibility,indicating their potential for multispecies use.Strains were susceptible to 17 out of 20 tested antibiotics,and displayed significant antimicrobial activity against Vibrio alginolyticus,Vibrio harveyi,Streptococcus iniae,and Streptococcus agalactiae.Therefore,AV5,AV7,and AV50 are promising probiotic candidates for enhancing the growth and health of aquatic animals,particularly in Nile tilapia(O.niloticus).展开更多
Inoculated fermentation enables rapid fermentation of aquatic products.No studies have been conducted on the lipid profiles of inoculated fermented golden pompano(Trachinotus ovatus).In this study,a lipase-producing B...Inoculated fermentation enables rapid fermentation of aquatic products.No studies have been conducted on the lipid profiles of inoculated fermented golden pompano(Trachinotus ovatus).In this study,a lipase-producing Bacillus subtilis with salt tolerance was screened from traditionally fermented golden pompano(TF)and used as a starter culture.Whole-genome sequencing analysis revealed it carries 4 clustered regularly interspaced short vpalindromic repeats structures and 2 genes encoding triacylglycerol lipase.Untargeted lipidomics identified lipid molecules(833)in 6 major classes from B.subtilis SCSMX-2 fermented golden pompano(IF).A total of 28 lipid molecules were upregulated in IF,including phosphatidylcholines(PCs),triacylglycerols(TAGs),and lysophosphatidylcholine.B.subtilis supplementation enhanced the production of polyenyl PCs and mediumand long-chain TAGs.The IF rich in linoleic,docosahexaenoic acids(DHA),and eicosapentaenoic acid were primarily distributed in the sn-2 position of DHA,PC and phosphatidylethanolamine.This research revealed the lipid profiles of IF,providing theoretical basis for the application of B.subtilis in the fermented fish industry.展开更多
文摘In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detection of Vibrio parahaemolyticus.The nanozyme integrated magnetic separation,peroxidase-like catalytic activity,and specific target recognition through an aptamer-based strategy.Upon binding to V.parahaemolyticus,the catalytic oxidation of tetra-aminophenylethylene(TPE-4A)by the nanozyme was selectively inhibited,resulting in distinct colorimetric and fluorescent signals that significantly enhanced the detection accuracy and reliability.The proposed method exhibited high sensitivity,with limits of detection(LOD)of 21 and 7 CFU/mL for the colorimetric and fluorescent assays,respectively.The performance of this method was validated using real seafood samples,including Penaeus vannamei,Mytilus coruscus,and Crassostrea gigas,which showed high recovery rates(101.11%-107.30%)and excellent reproducibility.The system also demonstrated strong specificity and accuracy under various conditions,confirming its robustness and practical applicability.Collectively,this innovative platform presents a promising solution for the rapid,versatile,and sensitive detection of V.parahaemolyticus in seafood,with considerable potential to advance food safety diagnosis and on-site monitoring.
文摘Microplastics,resulting from human activities,are widespread environmental contaminants that threaten both ecosystems and human health.These particles,less than 5 mm in size,are found in air,soil,and water,originating from industrial waste and everyday plastic products.They come in various shapes,sizes,and colors,with primary and secondary microplastics formed through degradation processes.Microplastics have entered the food chain,affecting all trophic levels,with detrimental effects on organisms such as plankton,fish,and corals.Research on microplastics is hindered by methodological biases and sampling inconsistencies,which impact the reliability and comparability of data,as different techniques often yield varying results.Current degradation methods,including bioremediation and filtration,show potential but remain limited.Detecting microplastics is challenging due to their small size,though advanced techniques like morphological and analytical analyses,particularly in fish guts,aid detection.Targeted studies on microplastic levels in aquatic species are crucial,and the development of biodegradable alternatives is essential to mitigate their long-term environmental impact.
基金Supported by the National Key Research and Development Program of China(No.2017YFC1404301)the National Natural Science Foundation of China(Nos.41230961,41176088)。
文摘The dinoflagellates Alexandrium pacificum and Prorocentrum donghaiense are two well-known harmful algal blooms(HABs)-forming species,both were usually found in the same sea areas in form of HABs in China.To date,there is no mechanistic model that can fully explain the occurrence of P.donghaiense blooms with A.pacificum.We found that different strains of P.donghaiense had different intrinsic growth rates of 0.107-0.215/d,and these strains exhibited different responses to the allelopathic action from A.pacificum.Some strains of P.donghaiense could grow well despite some degrees of inhibition in a short period,suggesting the two algal species P.donghaiense and A.pacificum could coexist,even if A.pacificum was allelopathic.Our findings may advance the understanding of phenotypes in P.donghaiense and provide a potential mechanism involved in the coexistence of P.donghaiense and A.pacificum in the same area.
基金supported by the National Natural Science Foundation of China(No.42307090)the Open Subject from State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in theMiddle and Lower Reaches of Yangtze River(No.AEHKF2023008).
文摘The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.
文摘Withania somnifera(L.)Dunal(WS),or Ashwagandha,is used clinically against arthritis,anxiety and insomnia etc,however,its potential in aquafeeds is largely unexplored.We investigated the stress-alleviation and hepatoprotective mechanisms of dietary WS supplementation in adult female darkbarbel catfish.Fish were fed with WS dietary for 5 weeks,subjected to a physical stressor(saline injection),and sampled.Brain were processed for RNA-seq to identify differentially expressed genes(DEGs)linked to stress;serum were assayed for stress-and immune-related biochemical markers;livers were examined for lipid content(Oil Red O staining)and proliferation(PCNA immunos-taining).Network pharmacology were employed to construct a"compound-target"net-work:The bioactive compounds of WS were retrieved from ChEBI and PCIDB,probable targets predicted via Swiss Target Prediction,and the“WS-ingredient-target”regulatory network was constructed using Cytoscape;key ligand-protein interactions were validated by molecular docking.Findings were replicated in juvenile fish and in SG3 cells challenged with Withanolide A.Physical stress evoked 1451 DEGs in control brains,whereas WS-supplemented reduced this to 397,indicating marked mitigation of the oxid-ative-and immune-stress response.Network pharmacology and molecular docking pre-dicted that 13 bioactive compounds in WS,especially Withanolide A and Withanolide J,can interact with targets such as MAPK8,CRHR1,NR3C2,and IARS1,being associated with stress and liver function regulation respectively.Moreover,it was proved that Withanolide A could significantly modulate stress response in juveniles and enhanced pro-liferation potency of SG3 cells.Intriguingly,in theadult female darkbarbel catfish,dietary WS lowered serum cortisol,glucose,ROS,TNF-α,and IL-6(P<0.05),up-regulated hepatocyte PCNA expression,and allievated stress-induced liver injury.These findings provide novel insights and vital basis for elucidating the mechanisms whereby herbs,including WS act in stress-relief and hepatoprotection in darkbarbel catfish.And provide a framework for advancing traditional Chinese medicine(TCM)applications in aquaculture.
基金supported by the National Natural Science Foundation of China(No.50808128).
文摘Perfluorooctanoic acid(PFOA),a novel contaminant,is extensively found in aquatic environments.However,the capability of the denitrifying phosphorus removal process to treat PFOA-containing wastewater,as well as its response mechanisms,are unclear.This study used batch experiments to assess the short-term impact of PFOA on denitrifying phosphorus removal systems.During a single cycle,the addition of PFOA predominantly enhanced phosphate removal in the system mainly by the anaerobic phosphorus release pathway,but had no substantial effect on nitrogen removal.COD removal efficiency has a substantial positive correlation with C6-HSL and C8-HSL concentrations.As the PFOA concentration increased,the ROS concentration and enzyme activity also increased,while the PN/PS ratio decreased,causing the sludge to become looser.At the beginning of the second cycle,the impact of PFOA on phosphorus removal efficiency shifted from promotion to inhibition.These findings shed fresh light on the influence of PFOA on the denitrifying phosphorus removal mechanism,potentially furthering its use in the treatment of fluoride-containing wastewater.
基金Supported by the National Natural Science Foundation of China(No.32370215)。
文摘The functional diversity index of a phytoplankton body has gradually become a new mean of measuring and research.To explore the response of phytoplankton taxonomy and the functional diversity index to interannual environmental changes,a survey on the structure of the phytoplankton community and water physicochemical characteristics of the water was carried out at 28 sampling points in the Harbin section of the Songhua River for three consecutive years in every May from 2021 to 2023.The taxonomy diversity index and the functional diversity index were calculated.Firstly,The relationship between the structure of the characteristics of the community and environmental factors was explored;secondly,we reveal the responses of taxonomic and functional diversity indices to different habitats between years;finally,we explore the main environmental factors that control the taxonomic and functional diversity indices of phytoplankton.Results show that,initially,environmental factors in water changes caused by different water levels between years affected the composition of phytoplankton communities.Subsequently,by comparing the taxonomic diversity index and the functional diversity index on a time scale,we found that the taxonomic diversity index was more responsive to environmental changes.Ultimately,the main environmental factors on the phytoplankton taxonomic diversity index were dissolved oxygen,Taxonomic diversity index,and specific conductivity,and the main environmental factors that affected the functional diversity index were dissolved oxygen,turbidity,and water temperature.This study reveals the important role of the taxonomic diversity index in river water quality evaluation,obtained new information on the relative precision of the taxonomic diversity index and the functional diversity index in the evaluation of ecological health of the water,and provided a reliable tool for monitoring river water quality based on aquatic organisms.
文摘The East China Sea(ECS)off the Coast of Zhoushan Archipelago,Zhejiang(ECS-CZA)is home to abundant fishery resources and an important spawning,feeding,and nursing ground for a variety of fish species.Due to long-term overfishing,the ichthyoplankton structure has been dramatically altered.Understanding the species composition and distribution of fish eggs and larvae is one of the most essential tasks to accurately regulate fishery resources and formulate effective management policies;however,little is known about the ichthyoplankton in this region.In this study,an integrated strategy of morphology identification(MI)and mitochondrial COI DNA barcoding was used to identify species of fish eggs and larvae collected from the ECSCZA.MI revealed 15 fish egg species belonging to 12 families and 12 fish larva species belonging to 12 families;in contrast,DNA barcoding altogether identified 30 species,including 18 fish egg species and 13 fish larva species.One species was shared between the egg and larva samples.Our study offers useful tools and critical scientific information for further understanding the diversity,distribution,and conservation management of various ichthyoplankton species in the marine environment.
基金Natural Science Foundation of Guangdong Province(2025A1515011061)Outstanding Graduate Entering Laboratory Project of College of Fisheries,Guangdong Ocean University+1 种基金Undergraduate Innovation and Entrepreneurship Training Program of Guangdong Ocean University(CXXL2024007)Undergraduate Innovation Team of Guangdong Ocean University(CCTD201802).
文摘[Objectives] To analyze the function of cobQ gene from Vibrio alginolyticus strain HY9901,and to provide a reference for exploring the possible mechanism of cobQ gene from V.alginolyticus.[Methods] A pair of primers were designed based on the sequence of the V.alginolyticus cobQ gene and used to amplify the full-length gene by PCR.[Results] The PCR amplification results indicated that the cobQ gene has a full length of 780 bp,encoding 259 amino acid residues.The deduced amino acid sequence predicts a molecular weight of approximately 28.83 kD and an isoelectric point of 9.21.Sequence analysis revealed no N-terminal signal peptide cleavage site,suggesting the absence of both a signal peptide and transmembrane regions in this protein.The amino acid sequence contains 2 N-terminal myristoylation sites,1 N-glycosylation site,1 glycosaminoglycan attachment site,4 microbody C-terminal targeting signal sites,3 casein kinase II phosphorylation sites,and 4 protein kinase C phosphorylation sites.Subcellular localization prediction showed that the CobQ protein is primarily localized in the cytoplasm(65.2%probability).Homology analysis demonstrated that the amino acid sequence of the cobQ gene from V.alginolyticus shares up to 99%homology with other Vibrio species,clustering within the same subclade as Vibrio parahaemolyticus,indicating close phylogenetic relationships.Secondary structure prediction revealed proportions ofα-helices,random coils,and extended strands as 44.40%,36.68%,and 18.92%,respectively.The tertiary structure model exhibited 87.62%similarity to the template A0A165XBE1.1.[Conclusions] In this study,the V.alginolyticus cobq gene was successfully cloned and its sequence was analyzed by bioinformatics.It is expected to lay a foundation for the subsequent study of the regulatory mechanism of its protein on the virulence of V.alginolyticus.
基金supported by the National Natural Science Foundation of China(No.42277404)the State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in the Middle and Lower Reaches of Yangtze River(No.AEHKF2023004)+2 种基金the National Key Research and Development Programof China(No.2022YFC3202703)the International Collaboration Program of Chinese Academy of Sciences(Nos.SAJC202403,067GJHZ2023034MI)the Autonomous Deployment Project of Key Laboratory of Lake andWatershed Science for Water Security(No.NKL2023-KP01).
文摘Polycyclic aromatic hydrocarbons(PAHs)are of great concern because they threaten pri-mary productivity,but their specific effects on ecosystem functioning are scarce,hindering a comprehensive understanding of their ecological risks,especially in eutrophicwaters.The present study was conducted by adding PAHs to four marine phytoplankton species and showed that naphthalene(Nap)and phenanthrene(Phe)induced both stimulatory and in-hibitory effects(>50%)on urea and NO_(3)−uptake by phytoplankton species.In addition,the apparent stimulative effects(>50%)for NH_(4)^(+)were also observed.Overall,38.9%of the sam-ples exhibited stimulation effects after 24 h exposure,which increased to 61.1%after 96 h exposure.This suggested the existence of a lag period,during which a tolerant cell popula-tion could adapt to PAHs.Significant positive correlations(P<0.01)between low and high concentrations of PAH individuals demonstrated that the mode of action for both pollutants on nitrogen uptake by phytoplankton was the same.Species-specific responses were also observed,with 19.0%of Thalassiosira sp.and 24.0%of Tetraselmis sp.exhibited inhibition effects greater than 50%,while 40.9%of Karlodinium veneficum and 27.3%of Rhodomonas salina demonstrated stimulation effects exceeding 50%,providing a unique perspective for exploring the harmful algal bloom of the mixotrophic K.veneficum,in addition to the original consideration of nutrients.The internal mechanisms may lie in differences in energy consumption between N-forms,exposure time and chemical concentrations,aswell as mor-phological characteristics and biochemical structures of the species,which require further investigation.
文摘Designing high-performance electrocatalysts is one of the key challenges in the development of microbial electrochemical hydrogen production.Transition metal-based(TM-based)electrocatalysts are introduced as an astonishing alternative for future catalysts by addressing several disadvantages,like the high cost and low performance of noble metal and metal-free electrocatalysts,respectively.In this critical review,a comprehensive analysis of the major development of all families of TMbased catalysts from the beginning development of microbial electrolysis cells in the last 15 years is presented.Importantly,pivotal design parameters such as selecting efficient synthesis methods based on the type of material,main criteria during each synthesizing method,and the pros and cons of various procedures are highlighted and compared.Moreover,procedures for tuning and tailoring the structures,advanced strategies to promote active sites,and the potential for implementing novel unexplored TM-based hybrid structures suggested.Furthermore,consideration for large-scale application of TM-based catalysts for future mass production,including life cycle assessment,cost assessment,economic analysis,and recently pilot-scale studies were highlighted.Of great importance,the potential of utilizing artificial intelligence and advanced computational methods such as active learning,microkinetic modeling,and physics-informed machine learning in designing high-performance electrodes in successful practices was elucidated.Finally,a conceptual framework for future studies and remaining challenges on different aspects of TM-based electrocatalysts in microbial electrolysis cells is proposed.
基金Supported by Natural Science Foundation of Guangdong Province(2025A1515011061)Outstanding Graduate Entering Laboratory Project of College of Fisheries,Guangdong Ocean University+1 种基金Undergraduate Innovation and Entrepreneurship Training Program of Guangdong Ocean University(CXXL2024007)Undergraduate Innovation Team of Guangdong Ocean University(CCTD201802).
文摘[Objectives]This study was conducted to investigate the functional characteristics of the trxB gene in Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the trxB gene sequence of V.alginolyticus for PCR cloning of its full-length sequence.Systematic bioinformatics analyses were conducted to predict the physicochemical properties,secondary structure,and tertiary structure of the encoded protein.[Results]The trxB gene is 960 bp in length,encoding 319 amino acid residues.The deduced protein has a predicted molecular weight of 34.32 kDa and an isoelectric point(pI)of 4.77.Analysis of the amino acid sequence revealed a distinct signal peptide cleavage site at the N-terminus,with no transmembrane domains.The functional sites are as follows:1 N-glycosylation site,1 cAMP-and cGMP-dependent protein kinase phosphorylation site,4 protein kinase C phosphorylation sites,7 casein kinase II phosphorylation sites,1 tyrosine kinase phosphorylation site,11 N-myristoylation sites,1 prenyl group binding site,3 microbody C-terminal targeting signal sites,and 1 xanthine nucleotide-disulfide oxidoreductase class II active site.Subcellular localization prediction indicated the highest probability(44.4%)for endoplasmic reticulum localization.The TrxB amino acid sequence of V.alginolyticus shares 97.2%-98.4%homology with other Vibrio species,and they were clustered within the same subgroup.Secondary structure prediction showed proportions of random coils(31.97%),alpha-helices(31.66%),extended strands(25.08%),and beta turns(11.29%).The tertiary structure model exhibited 88.68%similarity to template 5vt3.1.A.[Conclusions]This study elucidated the characterization of the TrxB protein in V.alginolyticus,laying a theoretical foundation for the development of outer membrane protein subunit vaccines against this pathogen.
基金Supported by Natural Science Foundation of Guangdong Province(2025A1515011061)Outstanding Graduate Entering Laboratory Project of College of Fisheries,Guangdong Ocean University+1 种基金Undergraduate Innovation and Entrepreneurship Training Program of Guangdong Ocean University(CXXL2024007)Undergraduate Innovation Team of Guangdong Ocean University(CCTD201802).
文摘[Objectives]To develop a pair of specific primers for the PCR amplification of the full-length relA gene from Vibrio alginolyticus strain HY9901,as well as to conduct bioinformatics analysis.[Methods]The relA gene was amplified through PCR,and the resulting gene sequence was subsequently analyzed using bioinformatics tools,including amino acid sequence prediction,functional site analysis,subcellular localization prediction,and homology comparison.[Results]The relA gene had a total length of 2220 bp and encoded 739 amino acid residues.The molecular weight was approximately 84.1261 kDa,and its isoelectric point was 5.95.The protein lacked a signal peptide and transmembrane regions,while exhibiting multiple phosphorylation sites.Predictions regarding its subcellular localization suggested that it was predominantly situated in the cytoplasm.The amino acid sequence demonstrated a homology of 97%to 99%with other species within the genus Vibrio,and it clustered within the same subfamily as V.antiquarius and V.diabolicus.In the prediction of secondary structure,the proportions ofα-helix,extended strand,random coil,andβ-sheet were 54.13%,12.04%,28.15%and 5.68%,respectively.The similarity between the tertiary structure model and template 5kpw.1.w was 66%.[Conclusions]In this study,the relA gene of V.alginolyticus strain HY9901 has been successfully amplified and analyzed.The structural characteristics and potential functions of the encoded protein have been elucidated,thereby providing foundational data for understanding the role of this gene in V.alginolyticus.
基金supported by the National Key Research and Development Program of China(2022YFD1201600)National Natural Science Foundation of China(32473156,32530106,32373106)Chongqing Fishery Technology Innovation Union(CQFTIU202501-7)。
文摘Current evidence supports high temperature-induced masculinization as the primary temperature-dependent sex determination(TSD)pattern in fish.To date,no study has reported bidirectional TSD in a fish species,in which low temperature induces masculinization while high temperature induces feminization.In this study,Onychostoma macrolepis exhibited a distinctive bidirectional TSD pattern,with a balanced 1:1 sex ratio at24°C(moderate temperature),over 80%female development at 28°C(high temperature),and approximately 75%male development at 20°C(low temperature).Transcriptomic analyses revealed kdm6bb and calcium channel genes as key regulators of TSD among the differentially expressed genes between high and low temperature groups.Consistently,administration of calcium influx and Kdm6bb inhibitors effectively blocked high temperature-induced feminization and low temperature-induced masculinization,respectively.These findings indicate that temperature perception in O.macrolepis is mediated through calcium signaling,which regulates the expression of the epigenetic modifier kdm6bb and consequently modulates sex determination.Unexpectedly,canonical male pathway genes such as dmrt1 and gsdf showed higher expression in the high temperature group than in the low temperature group at 50days after fertilization(daf).Administration of aromatase inhibitors failed to induce sex reversal at either temperature,whereas extremely low concentrations of testosterone/methyltestosterone(T/MT)and 17β-estradiol(E2)successfully induced sex reversal under high and low temperature conditions,respectively.These results suggest that downstream regulatory pathways controlling sexual differentiation in O.macrolepis are distinct from conventional TSD models.The discovery of this bidirectional mechanism establishes O.macrolepis as an exceptional model for elucidating the molecular and physiological bases of temperature-driven sex determination and underscores the ecological risks of global warming for aquatic vertebrates.
基金Supported by the Science and Technology Program of Guangdong Province(No.2022A1515010030)the National Natural Science Foundation of China(No.32102817)+3 种基金the Department of Education of Guangdong Province(Nos.2020ZDZX1045,2021KCXTD026)the earmarked fund for CARS-49,Students Innovation and Entrepreneurship Training Program(No.CXXL2022015)the Technology Program of Guangdong Zhanjiang(No.2022A01010)the Hengli Biosciences Excellence Project of Guangdong Ocean University(No.B23335-4)。
文摘Microplastics(MPs),particularly polyvinyl chloride microplastics(PVC MPs)have become a notable environmental pollutant that affect various marine organisms such as Pinctada fucata martensii.As filter feeders,these bivalves consume significant volumes of water containing MPs,leading to contact with and ingestion of MPs.Moreover,given the ecological and economic importance of P.f.martensii in artificial pearl production,investigating the effects of PVC MPs exposure is crucial.This study aimed to investigate the effects of PVC MPs exposure on nucleus retention,pearl formation,oxidative stress by examining superoxide dismutase(SOD)activity,catalase(CAT)activity,lipid peroxidation(LPO),and total antioxidant capacity(TAOC)of P.f.martensii,while also exploring transcriptomic changes at different concentrations and exposure time points,including a recovery period.The pearl oysters were exposed to PVC MPs at concentrations of 1-,2.5-,and 5-mg PVC MPs/L for 10 d followed by 6 d of recovery.After 1-,4-,10-d of exposure,and additional 6 d of recovery,samples were taken and analyzed.Findings revealed that only prolonged exposure(10 d)to PVC MPs affected SOD activity,while CAT activity,LPO,and TAOC remained unaffected throughout the experiment.Notably,SOD activity was restored during the 6-d recovery phase.Transcriptome analysis highlighted significant gene alterations linked to various pathways,affecting cellular processes,environmental information processing,genetic information processing,metabolism,and organismal systems,with an increase in pathway-related genes during recovery,implying a potential role of PVC MPs as gene inhibitors.This study provided insights into the effects of PVC MPs on P.f.martensii,shedding light on pearl retention,oxidative systems,and molecular pathways influenced by PVC MPs.Additionally,it contributed novel information on potential MPs exposure biomarkers,particularly relevant to marine organisms like P.f.martensii.
基金The National Natural Science Foundation of China under contract Nos U20A2065,32073006,and 32002426the Natural Science Foundation of Guangxi under contract No.2020GXNSFAA297243+3 种基金the Natural Science Foundation of Guangdong Province under contract No.2021B0202040002the Science and Technology Plan of Guangdong Province under contract No.2023B0202010016the Youth Science and Technology Innovation Talent of Guangdong TeZhi Plan Talent under contract No.2023TQ07A888the Science and Technology Planning Project of Zhanjiang under contract Nos 2022A01012 and 2022A01006.
文摘In this study,we aimed to isolate potential Bacillus strains from the digestive tract of Nile tilapia(Oreochromis niloticus).Through morphological,biochemical,16S rDNA sequencing,and evolutionary relationship assessments,we identified the isolated species as Bacillus amyloliquefaciens AV5(OR647358),Bacillus subtilis AV7(LC781790),and Bacillus velezensis AV50(OR647359),designated as AV5,AV7,and AV50 strains,respectively.We evaluated their probiotic potential,including tolerance to high bile salt concentrations,low pH levels,and high temperatures,as well as their adhesion abilities(auto-aggregation and cell-surface hydrophobicity),antimicrobial activity,biosafety,compatibility,hemolytic activity,and antibiotic susceptibility.AV5,AV7,and AV50 strains exhibitedγ-hemolytic activity and resistance to low pH(1)and high bile salt concentrations(0.5%).They demonstrated higher viability after exposure to elevated temperatures(80℃,90℃,and 100℃)and increased cell surface hydrophobicity and autoaggregation.These strains showed positive compatibility,indicating their potential for multispecies use.Strains were susceptible to 17 out of 20 tested antibiotics,and displayed significant antimicrobial activity against Vibrio alginolyticus,Vibrio harveyi,Streptococcus iniae,and Streptococcus agalactiae.Therefore,AV5,AV7,and AV50 are promising probiotic candidates for enhancing the growth and health of aquatic animals,particularly in Nile tilapia(O.niloticus).
基金supported by the National Natural Science Foundation of China(32372367)the earmarked fund for CARS(CARS-47)+1 种基金Natural Science Foundation of Hainan Provine(323CXTD391)the Special Scientific Research Funds for Central Non-profit Institutes and the Chinese Academy of Fishery Sciences(2020TD69)。
文摘Inoculated fermentation enables rapid fermentation of aquatic products.No studies have been conducted on the lipid profiles of inoculated fermented golden pompano(Trachinotus ovatus).In this study,a lipase-producing Bacillus subtilis with salt tolerance was screened from traditionally fermented golden pompano(TF)and used as a starter culture.Whole-genome sequencing analysis revealed it carries 4 clustered regularly interspaced short vpalindromic repeats structures and 2 genes encoding triacylglycerol lipase.Untargeted lipidomics identified lipid molecules(833)in 6 major classes from B.subtilis SCSMX-2 fermented golden pompano(IF).A total of 28 lipid molecules were upregulated in IF,including phosphatidylcholines(PCs),triacylglycerols(TAGs),and lysophosphatidylcholine.B.subtilis supplementation enhanced the production of polyenyl PCs and mediumand long-chain TAGs.The IF rich in linoleic,docosahexaenoic acids(DHA),and eicosapentaenoic acid were primarily distributed in the sn-2 position of DHA,PC and phosphatidylethanolamine.This research revealed the lipid profiles of IF,providing theoretical basis for the application of B.subtilis in the fermented fish industry.
