The production of fermented soymilk encounters technical challenges,including gel instability and unfavorable volatile flavor.Selecting appropriate starter strains may effectively address these issues.The present stud...The production of fermented soymilk encounters technical challenges,including gel instability and unfavorable volatile flavor.Selecting appropriate starter strains may effectively address these issues.The present study was designed to compare the application potential of Lactobacillus delbrueckii subsp.bulgaricus CGMCC 1.60194 and Enterococcus faecium CGMCC 29309,which were selected in our previous study,in preparing fermented soymilk and analyze their coagulation mechanisms.Results showed that the E.faecium-fermented soymilk exhibited superior firmness and viscosity compared to its L.bulgaricus-fermented counterpart.This improvement in textural quality was attributed to a higher D[4,3]value and enhanced intermolecular forces,collectively indicating a more robust gel structure in the E.faecium-fermented soymilk.In terms of volatile flavor properties,the E.faecium strain increased total aroma compound levels by 65.2%and reduced off-odor compound level by 99.3%,superior to those of the L.bulgaricus strain.In terms of nutritional properties,the L.bulgaricus strain reduced total oligosaccharide levels by 30.6%,while the E.faecium strain did not show this effect.Fermentation with the E.faecium strain led to a significant 51.5%increase in free fatty acid levels,while fermentation with the L.bulgaricus strain resulted in a 1.2-fold increase in free amino acid levels.Overall,the E.faecium strain demonstrated better capabilities in producing high-quality fermented soymilk,offering improved gel properties,volatile flavor profiles,and higher levels of free fatty acids compared to the L.bulgaricus strain.This research offers technical support for selecting appropriate lactic acid bacteria starters in premium fermented soymilk production.展开更多
Fermented milk is a typically product of co-fermentation by a variety of lactic acid bacteria(LAB).Quorum sensing(QS),as an intercellular communication mechanism of bacteria,may serve as a key factor influencing the q...Fermented milk is a typically product of co-fermentation by a variety of lactic acid bacteria(LAB).Quorum sensing(QS),as an intercellular communication mechanism of bacteria,may serve as a key factor influencing the quality of fermented milk.In this study,the fermentation performance of Lactobacillus delbrueckii subsp.bulgaricus DPUL-F36 were evaluated after supplementation with auto-inducer-2(AI-2).The protein-protein interaction network(PPIN)was used to retrieve the interactions between QS genes and four major metabolic pathway genes.The expression of luxS gene in DPUL-F36 may affect amino acid metabolism,carbohydrate metabolism and cell wall formation.The key differential metabolites were identified by metabolomics analysis.A variety of amino acids including L-Glutamic,L-Tryptophan,L-Threonine,L-Histidine and L-Glutamine were found to be upregulated in response to the addition of AI-2.Malic acid and succinate gradually accumulate in the tricarboxylic acid cycle.The consumption of citric acid increased with the fermentation process.In terms of rheological and texture characteristics of fermented milk,addition of AI-2 could effectively improve its shear stress resistance,firmness and index of viscosity.Our research provided a theoretical basis for improving the fermentation performance of DPUL-F36 strains,and support for the screening of excellent composite starter culture.展开更多
Microplastics have been detected in various foods,revealing potential pathways for their entry into the human body through the food chain.As the primary digestive organ,the gut is also a significant site for microplas...Microplastics have been detected in various foods,revealing potential pathways for their entry into the human body through the food chain.As the primary digestive organ,the gut is also a significant site for microplastic accumulation,yet effective strategies to mitigate gut damage caused by microplastic exposure remain to be explored.This study identified Lactobacillus delbrueckii subsp.bulgaricus strain JP006,which exhibits excellent acid tolerance,cell adhesion properties,and the ability to adsorb polystyrene microplastics(PS-MPs).Using cellular models combined with metabolomics analysis,the primary mechanism by which this strain alleviates PSMP-induced cellular damage was preliminarily revealed.Furthermore,its practical efficacy in mitigating PS-MPinduced intestinal damage was validated in a mouse model.Results indicate that JP006 alleviates PS-MPsinduced oxidative damage by enhancing antioxidant enzyme activity and reducing reactive oxygen species(ROS)levels;metabolomics analysis identified N-acetylglutamate as a key mediating substance.In mouse experiments,JP006 increased fecal PS-MPs excretion from 0.29 to 3.54μg/mL,significantly promoting PS-MPs efflux.16S rRNA amplicon data combined with Real-time Fluorescent Quantitative PCR(qPCR)results showed that JP006 not only restored microbial diversity but also increased the abundance of Lachnospiraceae and JP006 itself in the mouse gut,while reversing PS-MPs-induced overgrowth of Staphylococcus aureus,Enterococcus,and Prevotella.In summary,this study reports for the first time the role of Lactobacillus delbrueckii subsp.bulgaricus in adsorbing microplastics,promoting their intestinal excretion,and regulating intestinal permeability.These findings provide a theoretical basis for further developing this strain as a probiotic formulation to enhance microplastic excretion.展开更多
Lactobacillus delbrueckii subsp.bulgaricus(L.bulgaricus)and Streptococcus thermophilus(S.thermophilus)are commonly used starters in milk fermentation.Fermentation experiments revealed that L.bulgaricus-S.thermophilus ...Lactobacillus delbrueckii subsp.bulgaricus(L.bulgaricus)and Streptococcus thermophilus(S.thermophilus)are commonly used starters in milk fermentation.Fermentation experiments revealed that L.bulgaricus-S.thermophilus interactions(Lb St I)substantially impact dairy product quality and production.Traditional biological humidity experiments are time-consuming and labor-intensive in screening interaction combinations,an artificial intelligence-based method for screening interactive starter combinations is necessary.However,in the current research on artificial intelligence based interaction prediction in the field of bioinformatics,most successful models adopt supervised learning methods,and there is a lack of research on interaction prediction with only a small number of labeled samples.Hence,this study aimed to develop a semi-supervised learning framework for predicting Lb St I using genomic data from 362 isolates(181per species).The framework consisted of a two-part model:a co-clustering prediction model(based on the Kyoto Encyclopedia of Genes and Genomes(KEGG)dataset)and a Laplacian regularized least squares prediction model(based on K-mer analysis and gene composition of all isolates datasets).To enhance accuracy,we integrated the separate outcomes produced by each component of the two-part model to generate the ultimate Lb St I prediction results,which were verified through milk fermentation experiments.Validation through milk fermentation experiments confirmed a high precision rate of 85%(17/20;validated with 20 randomly selected combinations of expected interacting isolates).Our data suggest that the biosynthetic pathways of cysteine,riboflavin,teichoic acid,and exopolysaccharides,as well as the ATP-binding cassette transport systems,contribute to the mutualistic relationship between these starter bacteria during milk fermentation.However,this finding requires further experimental verification.The presented model and data are valuable resources for academics and industry professionals interested in screening dairy starter cultures and understanding their interactions.展开更多
Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by g...Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.展开更多
1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated fro...1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated from a 2 year old Bangladeshi child.长双歧杆菌幼儿亚种.展开更多
Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in...Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.展开更多
Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effec...Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effects of these 2 bifidobacterial species against Salmonella infection.The results demonstrated that B.longum subsp.infantis was more effective than B.adolescentis in alleviating the severity of infection in newborn rats exposed to Salmonella enterica serovar Typhimurium strain SL1344.B.longum subsp.infantis attenuated intestinal inflammation and mucosal damage induced by Salmonella infection,as well as protecting intestinal nerves and intestinal barrier function through TLR4/My D88 signalling.B.longum subsp.infantis also displayed the potential to modulate gut metabolites by promoting the biosynthesis of unsaturated fatty acids(arachidonic acid,eicosapentaenoic acid andα-linolenic acid)and purine metabolism(guanine,adenine,inosine and adenosine),thereby regulating metabolic disturbances.Additionally,the benefits of B.longum subsp.infantis were also observed in the liver,spleen and brain,improving nerve reflexes and suppressing hepatosplenomegaly.Overall,these findings provide novel insights into the prevention and treatment of gutrelated diseases in newborns,highlighting the potentially significant role of B.longum subsp.infantis in clinical applications.展开更多
基金supported by the National Natural Science Founda-tion of China(NSFC,Nos.31972057 and 32372306)the Qin-chuangyuan"Scientist+Engineer"Team Development Program of Shaanxi(No.2024QCY-KXJ-084)+2 种基金the Key Research and Development Program of Shaanxi(Nos.2023-YBNY-191 and 2024NC-YBXM-150)the Agricultural Technology Research and Development Project of Xi’an(No.2024JH-NYYB-0134)the Central Guidance for Local Science and Technology Development Funds Project(2024FDR05071).
文摘The production of fermented soymilk encounters technical challenges,including gel instability and unfavorable volatile flavor.Selecting appropriate starter strains may effectively address these issues.The present study was designed to compare the application potential of Lactobacillus delbrueckii subsp.bulgaricus CGMCC 1.60194 and Enterococcus faecium CGMCC 29309,which were selected in our previous study,in preparing fermented soymilk and analyze their coagulation mechanisms.Results showed that the E.faecium-fermented soymilk exhibited superior firmness and viscosity compared to its L.bulgaricus-fermented counterpart.This improvement in textural quality was attributed to a higher D[4,3]value and enhanced intermolecular forces,collectively indicating a more robust gel structure in the E.faecium-fermented soymilk.In terms of volatile flavor properties,the E.faecium strain increased total aroma compound levels by 65.2%and reduced off-odor compound level by 99.3%,superior to those of the L.bulgaricus strain.In terms of nutritional properties,the L.bulgaricus strain reduced total oligosaccharide levels by 30.6%,while the E.faecium strain did not show this effect.Fermentation with the E.faecium strain led to a significant 51.5%increase in free fatty acid levels,while fermentation with the L.bulgaricus strain resulted in a 1.2-fold increase in free amino acid levels.Overall,the E.faecium strain demonstrated better capabilities in producing high-quality fermented soymilk,offering improved gel properties,volatile flavor profiles,and higher levels of free fatty acids compared to the L.bulgaricus strain.This research offers technical support for selecting appropriate lactic acid bacteria starters in premium fermented soymilk production.
基金supported by the National Key Research and Development Program of China(2022YFD2100700).
文摘Fermented milk is a typically product of co-fermentation by a variety of lactic acid bacteria(LAB).Quorum sensing(QS),as an intercellular communication mechanism of bacteria,may serve as a key factor influencing the quality of fermented milk.In this study,the fermentation performance of Lactobacillus delbrueckii subsp.bulgaricus DPUL-F36 were evaluated after supplementation with auto-inducer-2(AI-2).The protein-protein interaction network(PPIN)was used to retrieve the interactions between QS genes and four major metabolic pathway genes.The expression of luxS gene in DPUL-F36 may affect amino acid metabolism,carbohydrate metabolism and cell wall formation.The key differential metabolites were identified by metabolomics analysis.A variety of amino acids including L-Glutamic,L-Tryptophan,L-Threonine,L-Histidine and L-Glutamine were found to be upregulated in response to the addition of AI-2.Malic acid and succinate gradually accumulate in the tricarboxylic acid cycle.The consumption of citric acid increased with the fermentation process.In terms of rheological and texture characteristics of fermented milk,addition of AI-2 could effectively improve its shear stress resistance,firmness and index of viscosity.Our research provided a theoretical basis for improving the fermentation performance of DPUL-F36 strains,and support for the screening of excellent composite starter culture.
基金supported by the Jiangsu Basic Research Center for Synthetic Biology Grant(No.BK20233003).
文摘Microplastics have been detected in various foods,revealing potential pathways for their entry into the human body through the food chain.As the primary digestive organ,the gut is also a significant site for microplastic accumulation,yet effective strategies to mitigate gut damage caused by microplastic exposure remain to be explored.This study identified Lactobacillus delbrueckii subsp.bulgaricus strain JP006,which exhibits excellent acid tolerance,cell adhesion properties,and the ability to adsorb polystyrene microplastics(PS-MPs).Using cellular models combined with metabolomics analysis,the primary mechanism by which this strain alleviates PSMP-induced cellular damage was preliminarily revealed.Furthermore,its practical efficacy in mitigating PS-MPinduced intestinal damage was validated in a mouse model.Results indicate that JP006 alleviates PS-MPsinduced oxidative damage by enhancing antioxidant enzyme activity and reducing reactive oxygen species(ROS)levels;metabolomics analysis identified N-acetylglutamate as a key mediating substance.In mouse experiments,JP006 increased fecal PS-MPs excretion from 0.29 to 3.54μg/mL,significantly promoting PS-MPs efflux.16S rRNA amplicon data combined with Real-time Fluorescent Quantitative PCR(qPCR)results showed that JP006 not only restored microbial diversity but also increased the abundance of Lachnospiraceae and JP006 itself in the mouse gut,while reversing PS-MPs-induced overgrowth of Staphylococcus aureus,Enterococcus,and Prevotella.In summary,this study reports for the first time the role of Lactobacillus delbrueckii subsp.bulgaricus in adsorbing microplastics,promoting their intestinal excretion,and regulating intestinal permeability.These findings provide a theoretical basis for further developing this strain as a probiotic formulation to enhance microplastic excretion.
基金supported by the National Key Research and Development Program of China(2022YFD2100700)the National Natural Science Foundation of China(32325040)+4 种基金Basic Scientific Research Business Fee Project of Universities Directly(BR22-14-01)the National Dairy Science and Technology Innovation Center(2022-Open Subject-6)Inner Mongolia Natural Science Foundation Project(2021MS06023)Inner Mongolia Science&Technology planning project(2022YFSJ0017)the earmarked fund for China Agricultural Research System(CARS36)。
文摘Lactobacillus delbrueckii subsp.bulgaricus(L.bulgaricus)and Streptococcus thermophilus(S.thermophilus)are commonly used starters in milk fermentation.Fermentation experiments revealed that L.bulgaricus-S.thermophilus interactions(Lb St I)substantially impact dairy product quality and production.Traditional biological humidity experiments are time-consuming and labor-intensive in screening interaction combinations,an artificial intelligence-based method for screening interactive starter combinations is necessary.However,in the current research on artificial intelligence based interaction prediction in the field of bioinformatics,most successful models adopt supervised learning methods,and there is a lack of research on interaction prediction with only a small number of labeled samples.Hence,this study aimed to develop a semi-supervised learning framework for predicting Lb St I using genomic data from 362 isolates(181per species).The framework consisted of a two-part model:a co-clustering prediction model(based on the Kyoto Encyclopedia of Genes and Genomes(KEGG)dataset)and a Laplacian regularized least squares prediction model(based on K-mer analysis and gene composition of all isolates datasets).To enhance accuracy,we integrated the separate outcomes produced by each component of the two-part model to generate the ultimate Lb St I prediction results,which were verified through milk fermentation experiments.Validation through milk fermentation experiments confirmed a high precision rate of 85%(17/20;validated with 20 randomly selected combinations of expected interacting isolates).Our data suggest that the biosynthetic pathways of cysteine,riboflavin,teichoic acid,and exopolysaccharides,as well as the ATP-binding cassette transport systems,contribute to the mutualistic relationship between these starter bacteria during milk fermentation.However,this finding requires further experimental verification.The presented model and data are valuable resources for academics and industry professionals interested in screening dairy starter cultures and understanding their interactions.
基金supported by the National Key R&D Programs of China(2022YFF0710701,2022YFF0710702)Guangzhou Key Research and Development Program(202206010157)+2 种基金Guangzhou Joint Fund for Key Laboratory(202201020381)Medical Joint Fund of Jinan University(YXJC202204)Open Research Project of the Key Laboratory of Viral Pathogenesis and Infection Prevention and Control of the Ministry of Education(2023VPPC-R02).
文摘Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.
文摘1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated from a 2 year old Bangladeshi child.长双歧杆菌幼儿亚种.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFD1200101)the Earmarked Fund for Modern Agro-industry Technology Research System(Grant No.CARS-23)Science and Technology Innovation Program of the Chinese Academy of Agricultural Science(Grant No.CAAS-ASTIP-IVFCAAS).
文摘Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.
基金supported by the National Natural Science Foundation of China(32021005,32272332)the Fundamental Research Funds for the Central Universities(JUSRP622020,JUSRP51501)+1 种基金the Program of Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu ProvincePostgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_2391)。
文摘Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effects of these 2 bifidobacterial species against Salmonella infection.The results demonstrated that B.longum subsp.infantis was more effective than B.adolescentis in alleviating the severity of infection in newborn rats exposed to Salmonella enterica serovar Typhimurium strain SL1344.B.longum subsp.infantis attenuated intestinal inflammation and mucosal damage induced by Salmonella infection,as well as protecting intestinal nerves and intestinal barrier function through TLR4/My D88 signalling.B.longum subsp.infantis also displayed the potential to modulate gut metabolites by promoting the biosynthesis of unsaturated fatty acids(arachidonic acid,eicosapentaenoic acid andα-linolenic acid)and purine metabolism(guanine,adenine,inosine and adenosine),thereby regulating metabolic disturbances.Additionally,the benefits of B.longum subsp.infantis were also observed in the liver,spleen and brain,improving nerve reflexes and suppressing hepatosplenomegaly.Overall,these findings provide novel insights into the prevention and treatment of gutrelated diseases in newborns,highlighting the potentially significant role of B.longum subsp.infantis in clinical applications.
