Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the ...Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products.展开更多
Here,we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage.Tandem mass tags(TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between pr...Here,we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage.Tandem mass tags(TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between protein changes and quality characteristics of modified atmosphere packaging(MAP)fillets during superchilling(-3°C)storage.Scanning electron microscopy was used to show that the muscle histology microstructure of fillets was damaged to varying degrees,and low-field nuclear magnetic resonance was used to find that the immobilized water and free water in the muscle of fillets changed significantly.Total sulfhydryl content,TCA-soluble peptides and Ca2+-ATPase activity also showed that the fillet protein had a deterioration by oxidation and denaturation.The Fresh(FS),MAP,and air packaging(AP)groups were set.Total of 150 proteins were identified as differential abundant proteins(DAPs)in MAP/FS,while 209 DAPs were in AP/FS group.The KEGG pathway analysis indicated that most DAPs were involved in binding proteins and protein turnover.Correlation analysis found that 52 DAPs were correlated with quality traits.Among them,8 highly correlated DAPs are expected to be used as potential quality markers for protein oxidation and water-holding capacity.These results provide a further understanding of the muscle deterioration mechanism of packaging golden pompano fillets during superchilling.展开更多
Quality deterioration induced by microbial community in Litopenaeus vannamei during superchilling storage were demonstrated in this study.In this study,6 microorganisms were identified as the biomarkers by 16S rDNA se...Quality deterioration induced by microbial community in Litopenaeus vannamei during superchilling storage were demonstrated in this study.In this study,6 microorganisms were identified as the biomarkers by 16S rDNA sequencing and 71 differential metabolites were identified by untargeted metabolomics.The correlation analysis between microorganisms and differential metabolites revealed that Oceanicaulis,Aliihoeflea,Prauserella,Chelativorans and Pseudoalteromonas had the potential to be the important microorganisms of deterioration of superchilled shrimp.Moreover,the spearman correlation analysis revealed that lightness value had highly significant correlation with Shewanella(P<0.01),and thiobarbituric acid content,total viable count value,total sulfhydryl content,trichloroacetic acid-soluble peptide and Ca2+-ATPase activity showed significantly correlation with Oceanicaulis,Prauserella,Chelativorans,Aliihoefl ea and Pseudoalteromonas(P<0.05).This study offers a better understanding for mechanisms behind quality degradation induced by microorganisms,which may help the quality maintaining of Pacific white shrimp during superchilling storage.展开更多
Fermented foods are a potential source to produce novel dipeptidyl peptidase-IV inhibitory peptides(D4IPs).In this study,the fermented mandarin fish(Chouguiyu)was used to screen D4IPs and their formation mechanism was...Fermented foods are a potential source to produce novel dipeptidyl peptidase-IV inhibitory peptides(D4IPs).In this study,the fermented mandarin fish(Chouguiyu)was used to screen D4IPs and their formation mechanism was studied by metagenomics and peptidomics.A total of 400 D4IPs with DPP-IV inhibition structure and high hydrophobicity were identified.The correlation network map showed that Lactococcus,Bacillus,Lysobacter,Pelagivirga,Kocuria,Escherichia,Streptococcus,and Peptostreptococcus were significantly correlated with the most D4IPs.Four stable D4IPs,including KAGARALTDAETAT,GEKVDFDDIQK,VVDADEMYLKGK,and GQKDSYVGDEAQ were respectively from the precursor proteins parvalbumin,troponin,myosin,and actin,and were mainly formed by the hydrolysis of subtilisin(EC 3.4.21.62),aspartic proteinase(EC 3.4.23.1),thermolysin(EC 3.4.24.27),oligopeptidase B(EC 3.4.21.83),and proteinase P1(EC 3.4.21.96)from Bacillus,Kocuria,Lysobacter,Lactococcus,and Peptostreptococcus.The inhibition mainly resulted from the hydrogen bond and salt bridge between D4IPs and DPP-IV enzyme.This study provides important information on the proteases and related microbial strains to directionally prepare D4IPs in Chouguiyu.展开更多
Volatile organic compounds are important indicators of the characteristic flavor of traditional fermented fish products. In the present study, gas chromatography-ion mobility mass spectrometry (GC-IMS) and gas chromat...Volatile organic compounds are important indicators of the characteristic flavor of traditional fermented fish products. In the present study, gas chromatography-ion mobility mass spectrometry (GC-IMS) and gas chromatography-mass spectrometry (GC-MS) were used to identify and quantify the volatile organic compounds (VOCs) in fermented sea bass. Thirty-six and 104 VOCs were identified by GC-IMS and GC-MS, respectively. Aldehydes were the principal contributors to the formation of the overall flavor of fermented sea bass. The characteristic VOCs in fermented sea bass were identified based on loading plots. GC-IMS and GC-MS, along with variable influence on projection (VIP), identified six and four VOCs as biomarkers, respectively, in fermented sea bass. This investigation demonstrated that GC-IMS could rapidly detect VOCs in a simple manner in fermented sea bass. The results of the present study also provide a theoretical basis for determining flavor formation in fermented sea bass.展开更多
This study aimed to isolate and identify the novel potential Xanthine oxidase(XOD)inhibitory peptides derived from Trachinotus ovatus hydrolysate(TOH)(hydrolysis by neutral protease),and investigate their structure-fu...This study aimed to isolate and identify the novel potential Xanthine oxidase(XOD)inhibitory peptides derived from Trachinotus ovatus hydrolysate(TOH)(hydrolysis by neutral protease),and investigate their structure-function relationship.Initially,TOH was separated to four fractions(F1–F4)by gel filtration chromatography and F4 was chosen with higher XOD inhibitory rate(85.16%±0.566,25 mg/mL)and lower molecular weight(95.73%,<1000 Da).F4 was further characterized by reversed-phase high performance liquid chromatography(RP-HPLC)coupled with Nano-HPLC-MS/MS and four peptides(FPAW,LLPW,WLLP and FHLP)were identified with IC50 value of 3.81±0.18 mM,4.17±0.12 mM,43.06±0.73 mM,and over 50.00 mM respectively.It can be concluded that Trp-containing peptides especially located in C-terminal could inhibit XOD effectively.Moreover,the XOD-inhibiting actions of these peptides involvedπ-πstacking(Phe914 and Phe1009 in XOD),hydrogen bonding via molecular docking.Lineweaver-Burk equation showed the inhibition type of FPAW was a mixed inhibition.Circular dichroism(CD)spectra indicated FPAW could combine and change the secondary structure of XOD.Therefore,two peptides of FPAW and LLPW might have potential to be used to alleviate hyperuricemia in the future.展开更多
We investigated the Fe^(2+)chelating properties and the mechanism of improving Fe^(2+)bioavailability of the Fe^(2+)chelating peptide(GLPGPSGEEGKR,peptide-G-R).Fe^(2+)was chelated with the carboxyl oxygen atom of the ...We investigated the Fe^(2+)chelating properties and the mechanism of improving Fe^(2+)bioavailability of the Fe^(2+)chelating peptide(GLPGPSGEEGKR,peptide-G-R).Fe^(2+)was chelated with the carboxyl oxygen atom of the Glu-Glu residue in the form of monodentate and bidentate chelating mode.After chelation,peptide-G-R was folded and aggregated to form spherical particles with increasing particle size.Peptide-G-R could increase the Fe^(2+)transport/retention/uptake rate and the relative expression levels of divalent metal transporter 1(DMT1)in the Caco-2 cells monolayer model.Peptide-G-R could reverse the inhibition of phytic acid on the Fe^(2+)utilization in the Caco-2 cells monolayer model.Molecular dynamics simulation showed that peptide-G-R interacted with DMT1 in the form of intermolecular hydrogen bonds.The transport mechanism of the peptide-G-R-Fe^(2+)complex included endocytosis(main pathway),paracellular pathway(auxiliary way),and DMT1(potential pathway).Thus,peptide-G-R derived from tilapia skin collagen could be used as a dietary iron supplement.展开更多
Ready-to-eat jellyfish production is restricted by the high aluminum residue and unable use of thermal sterilization.In this study,the combined dealumination and sterilization by slightly acidic electrolyzed water(SAE...Ready-to-eat jellyfish production is restricted by the high aluminum residue and unable use of thermal sterilization.In this study,the combined dealumination and sterilization by slightly acidic electrolyzed water(SAEW)were used to produce ready-to-eat jellyfish.The optimal aluminum removal amount reaching 120.17 mg/kg was obtained after response surface analysis.Structure observation through optical microscope after Masson staining and scanning electron microscope showed that the microstructure of jellyfish was not destroyed after SAEW treatment.The increase of total plate count(TPC)and pH value during storage was significantly inhibited by SAEW,while the other properties did not changed significantly.Staphylococcus,especially Staphylococcus epidermidis was dominant in the ready-to-eat jellyfish and many spoilage bacteria were inhibited by SAEW.The correlation network maps showed that Pseudomonas and Shewanella contributed most to the increase of TPC and pH value in the control group,while the correlated microbial genera mainly changed to Acinetobacter,Cutibacterium,and Pseudomonas after SAEW treatment,resulting in the decrease of hardness and chewiness of ready-to-eat jellyfish during storage.The inhibited Pseudomonas contributed most to the decrease of TPC and pH value after SAEW treatment.This study provides a novel technology of dealumination and sterilization for ready-to-eat jellyfish.展开更多
基金supported by the National Natural Science Foundation of China(32001733)the Earmarked fund for CARS(CARS-47)+3 种基金Guangxi Natural Science Foundation Program(2021GXNSFAA196023)Guangdong Basic and Applied Basic Research Foundation(2021A1515010833)Young Talent Support Project of Guangzhou Association for Science and Technology(QT20220101142)the Special Scientific Research Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences(2020TD69)。
文摘Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products.
基金supported by Central Public-Interest Scientific Institution Basal Research Fund,CAFS(2023TD74,2023TD78)the Earmarked Fund for CARS-47(CARS-47)+2 种基金Guangdong Provincial Science and Technology Plan Project(2023B0202010015)Central Public-Interest Scientific Institution Basal Research Fund,CAFS(Sanya Yazhou Bay Science and Technology City(SKJC-2020-02-013))Special Funds for Promoting Economic Development in Guangdong Province(For Modern Fishery)(YueNong 2019B14).
文摘Here,we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage.Tandem mass tags(TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between protein changes and quality characteristics of modified atmosphere packaging(MAP)fillets during superchilling(-3°C)storage.Scanning electron microscopy was used to show that the muscle histology microstructure of fillets was damaged to varying degrees,and low-field nuclear magnetic resonance was used to find that the immobilized water and free water in the muscle of fillets changed significantly.Total sulfhydryl content,TCA-soluble peptides and Ca2+-ATPase activity also showed that the fillet protein had a deterioration by oxidation and denaturation.The Fresh(FS),MAP,and air packaging(AP)groups were set.Total of 150 proteins were identified as differential abundant proteins(DAPs)in MAP/FS,while 209 DAPs were in AP/FS group.The KEGG pathway analysis indicated that most DAPs were involved in binding proteins and protein turnover.Correlation analysis found that 52 DAPs were correlated with quality traits.Among them,8 highly correlated DAPs are expected to be used as potential quality markers for protein oxidation and water-holding capacity.These results provide a further understanding of the muscle deterioration mechanism of packaging golden pompano fillets during superchilling.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2020A1515110360)Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City(320LH037)+3 种基金Hainan Provincial Natural Sciences Foundation of China(322QN434)Guangzhou Basic and Applied Basic Research Foundation(202102021062)Research and Development Projects in Key Areas of Guangdong Province,China(2021B0202060002)Postgraduate Education Innovation Project of Guangdong Ocean University(202242).
文摘Quality deterioration induced by microbial community in Litopenaeus vannamei during superchilling storage were demonstrated in this study.In this study,6 microorganisms were identified as the biomarkers by 16S rDNA sequencing and 71 differential metabolites were identified by untargeted metabolomics.The correlation analysis between microorganisms and differential metabolites revealed that Oceanicaulis,Aliihoeflea,Prauserella,Chelativorans and Pseudoalteromonas had the potential to be the important microorganisms of deterioration of superchilled shrimp.Moreover,the spearman correlation analysis revealed that lightness value had highly significant correlation with Shewanella(P<0.01),and thiobarbituric acid content,total viable count value,total sulfhydryl content,trichloroacetic acid-soluble peptide and Ca2+-ATPase activity showed significantly correlation with Oceanicaulis,Prauserella,Chelativorans,Aliihoefl ea and Pseudoalteromonas(P<0.05).This study offers a better understanding for mechanisms behind quality degradation induced by microorganisms,which may help the quality maintaining of Pacific white shrimp during superchilling storage.
基金financially supported by the National Key R&D Program of China(2019YFD0901903)the China Agriculture Research System of MOF and MARA(CARS-46,CARS-47)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2021A1515010872)the Young S&T Talent Training Program of Guangdong Provincial Association for S&T,China(SKXRC202210)the Pearl River S&T Nova Program of Guangzhou(201906010081)the Central Public-interest Scientific Institution Basal Research Fund,CAFS(2020TD69).
文摘Fermented foods are a potential source to produce novel dipeptidyl peptidase-IV inhibitory peptides(D4IPs).In this study,the fermented mandarin fish(Chouguiyu)was used to screen D4IPs and their formation mechanism was studied by metagenomics and peptidomics.A total of 400 D4IPs with DPP-IV inhibition structure and high hydrophobicity were identified.The correlation network map showed that Lactococcus,Bacillus,Lysobacter,Pelagivirga,Kocuria,Escherichia,Streptococcus,and Peptostreptococcus were significantly correlated with the most D4IPs.Four stable D4IPs,including KAGARALTDAETAT,GEKVDFDDIQK,VVDADEMYLKGK,and GQKDSYVGDEAQ were respectively from the precursor proteins parvalbumin,troponin,myosin,and actin,and were mainly formed by the hydrolysis of subtilisin(EC 3.4.21.62),aspartic proteinase(EC 3.4.23.1),thermolysin(EC 3.4.24.27),oligopeptidase B(EC 3.4.21.83),and proteinase P1(EC 3.4.21.96)from Bacillus,Kocuria,Lysobacter,Lactococcus,and Peptostreptococcus.The inhibition mainly resulted from the hydrogen bond and salt bridge between D4IPs and DPP-IV enzyme.This study provides important information on the proteases and related microbial strains to directionally prepare D4IPs in Chouguiyu.
基金supported by the National Natural Science Foundation of China[32001733]the Earmarked fund for CARS[CARS-46 and CARS-47]+2 种基金the Guangdong Basic and Applied Basic Research Foundation[2021A1515010833]Young Talent Support Project of Guangzhou Association for Science and Technology[QT20220101142]the Special Scientific Research Funds for Central Non-profit Institutes and Chinese Academy of Fishery Sciences[2020TD69].
文摘Volatile organic compounds are important indicators of the characteristic flavor of traditional fermented fish products. In the present study, gas chromatography-ion mobility mass spectrometry (GC-IMS) and gas chromatography-mass spectrometry (GC-MS) were used to identify and quantify the volatile organic compounds (VOCs) in fermented sea bass. Thirty-six and 104 VOCs were identified by GC-IMS and GC-MS, respectively. Aldehydes were the principal contributors to the formation of the overall flavor of fermented sea bass. The characteristic VOCs in fermented sea bass were identified based on loading plots. GC-IMS and GC-MS, along with variable influence on projection (VIP), identified six and four VOCs as biomarkers, respectively, in fermented sea bass. This investigation demonstrated that GC-IMS could rapidly detect VOCs in a simple manner in fermented sea bass. The results of the present study also provide a theoretical basis for determining flavor formation in fermented sea bass.
基金supported by the Key-Area Research and Development Program of Guangdong Province(2020B1111030004)the Guangdong Basic and Applied Basic Research Foundation(2019A1515011588)+4 种基金the Pearl River S&T Nova Program of Guangzhou(201906010081)the China Agriculture Research System of MOF and MARA(CARS-47)the Special Scientific Research Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences(2020TD69)the Central Public-interest Scientific Institution Basal Research Funds,South China Sea Fisheries Research Institute,CAFS(2021SD06)Qingdao Science and technology benefit people special project(20-3-4-31-nsh).
文摘This study aimed to isolate and identify the novel potential Xanthine oxidase(XOD)inhibitory peptides derived from Trachinotus ovatus hydrolysate(TOH)(hydrolysis by neutral protease),and investigate their structure-function relationship.Initially,TOH was separated to four fractions(F1–F4)by gel filtration chromatography and F4 was chosen with higher XOD inhibitory rate(85.16%±0.566,25 mg/mL)and lower molecular weight(95.73%,<1000 Da).F4 was further characterized by reversed-phase high performance liquid chromatography(RP-HPLC)coupled with Nano-HPLC-MS/MS and four peptides(FPAW,LLPW,WLLP and FHLP)were identified with IC50 value of 3.81±0.18 mM,4.17±0.12 mM,43.06±0.73 mM,and over 50.00 mM respectively.It can be concluded that Trp-containing peptides especially located in C-terminal could inhibit XOD effectively.Moreover,the XOD-inhibiting actions of these peptides involvedπ-πstacking(Phe914 and Phe1009 in XOD),hydrogen bonding via molecular docking.Lineweaver-Burk equation showed the inhibition type of FPAW was a mixed inhibition.Circular dichroism(CD)spectra indicated FPAW could combine and change the secondary structure of XOD.Therefore,two peptides of FPAW and LLPW might have potential to be used to alleviate hyperuricemia in the future.
基金supported by the National Key R&D Program of China(2018YFD0901102)the Key-Area Research and Development Program of Guangdong Province(2020B020226005)+4 种基金the China Agriculture Research System of MOF and MARA(CARS-46)he National Natural Science Foundation of China(31301454)the Special Scientific Research Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences(2020TD69)the Central Public-interest Scientific Institution Basal Research Funds,South China Sea Fisheries Research Institute,CAFS(2021SD06)the Pearl River S&T Nova Program of Guangzhou(201906010081).
文摘We investigated the Fe^(2+)chelating properties and the mechanism of improving Fe^(2+)bioavailability of the Fe^(2+)chelating peptide(GLPGPSGEEGKR,peptide-G-R).Fe^(2+)was chelated with the carboxyl oxygen atom of the Glu-Glu residue in the form of monodentate and bidentate chelating mode.After chelation,peptide-G-R was folded and aggregated to form spherical particles with increasing particle size.Peptide-G-R could increase the Fe^(2+)transport/retention/uptake rate and the relative expression levels of divalent metal transporter 1(DMT1)in the Caco-2 cells monolayer model.Peptide-G-R could reverse the inhibition of phytic acid on the Fe^(2+)utilization in the Caco-2 cells monolayer model.Molecular dynamics simulation showed that peptide-G-R interacted with DMT1 in the form of intermolecular hydrogen bonds.The transport mechanism of the peptide-G-R-Fe^(2+)complex included endocytosis(main pathway),paracellular pathway(auxiliary way),and DMT1(potential pathway).Thus,peptide-G-R derived from tilapia skin collagen could be used as a dietary iron supplement.
基金financially supported by the Guangdong Provincial Special Fund For Modern Agriculture Industry Technology Innovation Teams(2023KJ151)the Youth Talent Support Programme of Guangdong Provincial Association for Science and Technology(SKXRC202210)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund,CAFS(2020TD69)the Key Laboratory of Aquatic Product Processing,Ministry of Agriculture and Rural Affairs,China(NYJG201309).
文摘Ready-to-eat jellyfish production is restricted by the high aluminum residue and unable use of thermal sterilization.In this study,the combined dealumination and sterilization by slightly acidic electrolyzed water(SAEW)were used to produce ready-to-eat jellyfish.The optimal aluminum removal amount reaching 120.17 mg/kg was obtained after response surface analysis.Structure observation through optical microscope after Masson staining and scanning electron microscope showed that the microstructure of jellyfish was not destroyed after SAEW treatment.The increase of total plate count(TPC)and pH value during storage was significantly inhibited by SAEW,while the other properties did not changed significantly.Staphylococcus,especially Staphylococcus epidermidis was dominant in the ready-to-eat jellyfish and many spoilage bacteria were inhibited by SAEW.The correlation network maps showed that Pseudomonas and Shewanella contributed most to the increase of TPC and pH value in the control group,while the correlated microbial genera mainly changed to Acinetobacter,Cutibacterium,and Pseudomonas after SAEW treatment,resulting in the decrease of hardness and chewiness of ready-to-eat jellyfish during storage.The inhibited Pseudomonas contributed most to the decrease of TPC and pH value after SAEW treatment.This study provides a novel technology of dealumination and sterilization for ready-to-eat jellyfish.
