International journal of food microbiology最新文献

{"title":"Pink discoloration defects associated with microbial structure and metabolome changes in commercial bloomy cheeses","authors":"Françoise Irlinger ,&nbsp;Christine Keribin ,&nbsp;Anne-Sophie Sarthou ,&nbsp;Béatrice Laroche ,&nbsp;Sandra Helinck","doi":"10.1016/j.ijfoodmicro.2025.111363","DOIUrl":"10.1016/j.ijfoodmicro.2025.111363","url":null,"abstract":"<div><div>This study investigates pink discoloration defects in French bloomy rind soft cheeses, which can negatively affect product appearance, consumer acceptance, and lead to economic losses. Two batches of cheese from the same processing plant were analyzed: one with visible pink discoloration and one without, allowing for comparative analysis. A multi-omics approach was applied, combining microbial profiling (16S rRNA and ITS2 sequencing) and metabolomics (GC–MS and LC-MS) to identify the factors linked to the defect. Three microbial species showed significant differences in abundance depending on sample type (spoiled and unspoiled) and location on the cheese surface: <em>Penicillium camemberti, Psychrobacte</em>r group, and <em>Paeniglutamicibacter gangotriensis</em>. A positive correlation was observed between this group and salt concentration, as well as with multiple metabolites such as butanoic acid, acetic acid, aldehydes, ketones, esters, and terpenes. Notably, <em>P. gangotriensis</em> had never previously been detected in cheese. To test its role, model cheeses were inoculated with or without six strains of <em>P. gangotriensis</em> isolated from cheeses. Model cheeses containing the bacteria developed pink discoloration after 14 days of ripening, while controls remained unchanged after 20 days. These results strongly suggest that <em>P. gangotriensis</em> is responsible for the pink defect. Further research is needed to confirm this hypothesis by identifying the pigment's chemical structure and understanding the biotic and abiotic conditions that promote its production.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111363"},"PeriodicalIF":5.0,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144704898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying the impact of beer unit operations (mashing, fermentation, and maturation) on Bacillus thuringiensis behavior","authors":"Marcela Capuzzo Alvarez ,&nbsp;Viny Lanza Xavier ,&nbsp;Dionisio Pedro Amorim-Neto ,&nbsp;Anderson S. Sant'Ana","doi":"10.1016/j.ijfoodmicro.2025.111361","DOIUrl":"10.1016/j.ijfoodmicro.2025.111361","url":null,"abstract":"<div><div>This study investigates the germination and survival of <em>Bacillus thuringiensis</em> strains during different stages of the brewing process, considering the impact of pH, hop concentration, and physicochemical parameters. Three <em>B. thuringiensis</em> strains carrying hop resistance genes (horA, horC, or both) were evaluated in Pilsner-style beer during mashing, fermentation, and maturation. Results showed that mashing was the most critical stage, with bacterial counts decreasing by over 5 log₁₀ CFU/mL within 6–9 min, while fermentation and maturation allowed spore survival. Additionally, at pH 5.7, <em>B. thuringiensis</em> strain C:118 exhibited significant growth (<em>p</em> &lt; 0.05), whereas strains C:002 and C:206 remained stable. Hop type and concentration influenced bacterial inhibition, with boiling enhancing antimicrobial activity, suggesting the release of bioactive compounds. However, some hop varieties lacked inhibitory effects against <em>B. thuringiensis</em>, highlighting the need for quality control measures beyond sensory attributes like bitterness. These findings confirm that spore-forming bacteria can persist throughout brewing and, depending on the final product composition, may germinate and proliferate under favorable conditions.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111361"},"PeriodicalIF":5.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144696919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The fate of spore-forming bacteria throughout the gelatin processing","authors":"Graziele C. Stradiotto ,&nbsp;Caroline Heckler ,&nbsp;Alexandra A.I.A. Chincha ,&nbsp;Anderson S. Sant'Ana","doi":"10.1016/j.ijfoodmicro.2025.111355","DOIUrl":"10.1016/j.ijfoodmicro.2025.111355","url":null,"abstract":"<div><div>Gelatin is a natural protein soluble in water and extracted from animal collagen through thermal and chemical treatments. Its physicochemical properties make it valuable for various applications in the food and pharmaceutical industries. Ensuring its microbiological quality is essential for maintaining its properties and ensuring the safety of products that use it as a raw material. This study analyzed the concentrations of four groups of spore-forming microorganisms (aerobic mesophiles, presumptive <em>Bacillus cereus</em>, aerobic thermophiles, and anaerobic mesophiles) throughout all stages of gelatin processing at three seasons of the year (spring, summer, autumn). A total of 600 samples were collected from a single plant located in São Paulo, Brazil. The isolated microorganisms were identified through 16S rRNA gene sequencing. Significant differences in the concentrations of spores of these groups were observed and analyzed using ANOVA and PLS-DA methods. The highest log-reductions of spores were observed as follows: aerobic mesophiles showed a log-reduction of γ = <span><math><mo>−</mo></math></span>1.9 from the extrusion to the final product; <em>B. cereus</em> showed a log-reduction of γ = <span><math><mo>−</mo></math></span>1.9 from the raw material to the pre-washing; aerobic thermophiles had a log-reduction of γ = <span><math><mo>−</mo></math></span>1.6 from the raw material to the pre-washing; and anaerobic mesophiles had a log-reduction of γ = <span><math><mo>−</mo></math></span>1.1 from the concentrated tank to the sterilization. Sequencing identified <em>B. cereus</em> group members, <em>B. licheniformis</em>, <em>Geobacillus</em> sp., <em>Clostridium</em> sp., <em>Lysinibacillus</em> sp., and <em>Brevibacillus</em> sp. These findings are significant for industry, as some of these microorganisms produce toxins harmful to humans and contribute to product deterioration through the production of gelatinases.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111355"},"PeriodicalIF":5.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation, genomic characterization and biocontrol potential of the lytic Pectobacterium phage Pcc_P10 against soft rot of pepper fruits","authors":"Mengtian Jiang ,&nbsp;Jinghan Zhang ,&nbsp;Cengceng Huang ,&nbsp;Zhuangzhuang Gao ,&nbsp;Siyue Chen ,&nbsp;Ping Zeng ,&nbsp;Ning Dong ,&nbsp;Xiaoxiao Sun ,&nbsp;Wentao Chen ,&nbsp;Xiaoxiao Liang ,&nbsp;Peng Lu ,&nbsp;Lanhua Yi ,&nbsp;Qipeng Cheng","doi":"10.1016/j.ijfoodmicro.2025.111360","DOIUrl":"10.1016/j.ijfoodmicro.2025.111360","url":null,"abstract":"<div><div><em>Pectobacterium carotovorum</em> (PBC) is a major plant pathogen responsible for soft rot disease in peppers, and its prevention and control remain highly challenging. In this study, a novel lytic phage targeting <em>Pectobacterium carotovorum</em> subsp. <em>carotovorum</em> (PCC), designated as Pcc_P10, belonging to the Pektosvirus genus within the Autographiviridae order, was isolated and characterized. The dsDNA genome sequence of Pcc_P10 was 39,637 bp with 49.1 % GC content, encoding 46 open reading frames without tRNA genes and virulence factor genes. Pcc_P10 exhibits specific lytic activity lysing only PCC among a panel of tested bacterial species. Compared to previously reported Pectobacterium phages, Pcc_P10 exhibits a uniquely broad pH tolerance (5–11), a shorter latent period with rapid lytic activity, and a compact genome devoid of tRNA and virulence genes, highlighting its robustness, efficiency, and biosafety as a biocontrol agent. <em>In vitro</em> assays revealed that Pcc_P10 significantly inhibits bacterial growth and disrupts biofilm formation, which has strong potential as a biocontrol agent. <em>In vivo</em> application of Pcc_P10 to infected green peppers resulted in a substantial reduction in soft rot symptoms and a concomitant decrease in PCC populations, demonstrating its efficacy as a biocontrol agent under experimental conditions. Given the growing global concerns regarding the environmental impact and sustainability of chemical pesticides, these findings support Pcc_P10 as a promising candidate for the development of sustainable biocontrol strategies against pepper soft rot.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111360"},"PeriodicalIF":5.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temperature-mediated shift from competitive to facilitative interactions between lactic acid bacteria and bacillus species in daqu fermentation: Insights from metagenomics, dual RNA-seq, and coculture analysis","authors":"Liming Wu ,&nbsp;Meiyu Yan ,&nbsp;Xinlei Huang ,&nbsp;Hui Liao ,&nbsp;Daixiu Bao ,&nbsp;Yitong Ge ,&nbsp;Shuaijun Wang ,&nbsp;Xiaole Xia","doi":"10.1016/j.ijfoodmicro.2025.111352","DOIUrl":"10.1016/j.ijfoodmicro.2025.111352","url":null,"abstract":"<div><div><em>Daqu</em>, a pivotal starter that defines the flavor profile and quality of <em>Baijiu</em>, undergoes dynamic temperature changes during its production, significantly influencing the microbial community structure and function. Although the importance of fermentation temperature in shaping microbial biodiversity is well-recognized, its impact on microbial interaction dynamics and the underlying mechanisms remains poorly understood. This study integrates metagenomics, dual RNA-seq, and coculture experiments to elucidate temperature-dependent microbial interactions during <em>Daqu</em> fermentation. Metagenomic analysis revealed that lactic acid bacteria (LAB) and <em>Bacillus</em> are dominant genera with distinct thermal preferences that nevertheless coexist throughout the fermentation process. Elevated temperature stress was found to enhance positive microbial interactions within the <em>Daqu</em> ecosystem. Dual RNA-seq analysis uncovered temperature-responsive gene expression patterns associated with oxidative stress, metabolic capacity, and environmental information processing in representative LAB and <em>Bacillus</em> strains. Guided by these multi-omics findings, co-culture assays demonstrated a temperature-dependent shift in microbial interaction modes. At 30 °C, <em>Lactococcus lactis</em> secretes lactic acid that inhibits the growth of <em>Bacillus subtilis</em>, whereas at 50 °C, <em>B. subtilis</em> alleviates oxidative stress in <em>L. lactis</em> by producing cobalamin, thereby enabling short-term rescue and sustained coexistence over serial transfers. These findings provide critical insights into the temperature-driven modulation of microbial interactions, enhancing the precision and manageability of the <em>Daqu</em> fermentation process.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111352"},"PeriodicalIF":5.0,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the healthy potential of goat milk fermented by novel isolated lactic acid bacteria: Genetic identification, bioactive peptides, nutritional mechanism and sensory evaluation","authors":"Zongcai Zhang ,&nbsp;Guowei Shu ,&nbsp;Jianhao Nan ,&nbsp;Fanbo Meng ,&nbsp;Meng Zhang ,&nbsp;Li Chen","doi":"10.1016/j.ijfoodmicro.2025.111354","DOIUrl":"10.1016/j.ijfoodmicro.2025.111354","url":null,"abstract":"<div><div>Lactic acid bacteria (LAB) ferment milk to produce bioactive peptides to benefit human health. In this study, a total of 74 LAB strains were used to ferment goat milk, and two novel strains, <em>Lactobacillus delbrueckii</em> MF55 and <em>Lacticaseibacillus paracasei</em> MF48, were identified with strong angiotensin-converting enzyme (ACE) inhibitory activity 70.73 % and antioxidant activity 63.33 %, respectively. Following ultrafiltration, QExactive identification, <em>in silico</em> simulations, and <em>in vitro</em> assay, five peptides (MPFPK, EMPFPK, FFDDK, GPFPILV, TTMPLW) were collected. Among them, peptide TTMPLW exhibited the strongest ACE inhibitory (IC₅₀ 115.55 μM) and antioxidant (IC₅₀ 2.57 mM) activities, followed by GPFPILV (232.96 μM and 10.27 mM). Molecular docking simulation suggested that peptides TTMPLW and GPFPILV were dual-target ligands for ACE and Keap1. Goat milk fermented by MF55 maintained stable bioactivity and favorable sensory properties during 28 days of cold storage. Our study provided two novel LAB strains with excellent dual-functional activity to help the development of functional dairy products.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111354"},"PeriodicalIF":5.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Different starter cultures regulate the histamine, physicochemical properties, microbial community and volatile compounds during sour bamboo shoot fermentation","authors":"Xiaoyi Du ,&nbsp;Jun Li ,&nbsp;Yujuan Xu,&nbsp;Jijun Wu,&nbsp;Jian Peng,&nbsp;Lina Cheng,&nbsp;Tenggen Hu,&nbsp;Yuanshan Yu,&nbsp;Lu Li","doi":"10.1016/j.ijfoodmicro.2025.111351","DOIUrl":"10.1016/j.ijfoodmicro.2025.111351","url":null,"abstract":"<div><div>To select fermenter for controlling the histamine content of sour bamboo shoots, the histamine content of 16 commercially available sour bamboo shoots was first determined. Histamine was detected in all the samples, with 11 samples exceeding the histamine guideline (50 mg/kg) of US Food and Drug Administration. Subsequently, <em>Lactiplantibacillus plantarum</em> CY087 (20.51 %), <em>Pediococcus pentosaceus</em> CYB89 (17.52 %) and <em>P. pentosaceus</em> CYC67 (12.23 %) with higher histamine degradation capacities were screened from sour bamboo shoots samples, which were used as starter cultures to ferment the sour bamboo shoots. Compared with <em>L. plantarum</em> CY087, the histamine contents of sour bamboo shoots fermented by <em>P. pentosaceus</em> CYB89 (19.35 mg/kg) and <em>P. pentosaceus</em> CYC67 (21.16 mg/kg) were below 50 mg/kg. Moreover, <em>P. pentosaceus</em> CYB89 and <em>P. pentosaceus</em> CYC67 were also could reduce the nitrite peak of sour bamboo shoots. The influence of histamine degradation strains on the microbial community and volatile flavor compounds of sour bamboo shoots were also investigated. The microbial community succession was greatly impacted by histamine degradation strains, and the <em>Priestia</em>, <em>Lactiplantibacillus</em> and <em>Escherichia</em> genera had closely related with histamine production, while <em>Pediococcus</em> genus showed a negative correlation with histamine generation. Acetic acid, propionaldehyde, butanal, ethyl crotonate and ethyl lactate were the characteristic flavor substances in sour bamboo shoot, and the volatile flavor composition of the <em>P. pentosaceus</em> CYC67 fermentation group showed the highest similarity (82 %) to that of the natural fermentation group. Above results suggested that <em>P. pentosaceus</em> CYC67 was a potential starter culture for the production of high-quality sour bamboo shoots.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111351"},"PeriodicalIF":5.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DNA metabarcoding for the identification and relative abundance assessment of general and potentially pathogenic bacteria in Sardinian sheep cheese processing environments","authors":"L. Giagnoni ,&nbsp;S. Salza ,&nbsp;A. Tondello ,&nbsp;G. Zardinoni ,&nbsp;Deb. Saptarathi ,&nbsp;G. Piras ,&nbsp;R. Melillo ,&nbsp;A. Cecchinato ,&nbsp;P. Stevanato ,&nbsp;T. Tedde ,&nbsp;A.G. Mudadu ,&nbsp;A. Squartini ,&nbsp;C. Spanu","doi":"10.1016/j.ijfoodmicro.2025.111353","DOIUrl":"10.1016/j.ijfoodmicro.2025.111353","url":null,"abstract":"<div><div>In dairy processing facilities, microbial contamination poses significant challenges to food safety and quality, even under rigorous hygiene protocols as those implemented in sheep milk processing in Sardinia. Specific niches within factories facilitate the persistence of spoilage and pathogenic microorganisms, including <em>Listeria monocytogenes</em>, <em>Salmonella</em> spp., <em>Bacillus cereus</em>, and <em>Pseudomonas</em> spp. Hereby, 16S rRNA-based bacterial metabarcoding was applied to assess bacterial populations in Sardinian cheese processing environments. The scope was to acquire taxonomical information on the total microbiota, including the presence of taxa known to feature also potentially pathogenic strains. Samples were collected from 14 dairy plants distributed throughout Sardinia, analyzing nine areas of the cheese processing line and their workflow pieces, distinguishing food-contact from non-food-contact surfaces, for a total of 253 samples. Five sequencing runs yielded 51,114,952 quality-filtered reads, resulting, upon bioinformatic processing, in 4426 annotated taxonomic lineages. A clear community partition driver within the technical workflow, was identified upon grouping the areas of washing-processing apart from those of salting-aging-shelving. Notably, the genus <em>Halomonas</em> and the family Halomonadaceae dominated and differentiated the microbial composition across samples. Sequences which belong to potential pathogens were instead prevailingly in the opposite sites when compared to salt-adapted biota.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111353"},"PeriodicalIF":5.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiological mechanisms and transcriptomic analysis of the disease resistance in pear fruit induced by Debaryomyces hansenii","authors":"Lina Zhao,&nbsp;Xiaoyue Ren,&nbsp;Ruyu Wen,&nbsp;Solairaj Dhanasekaran,&nbsp;Xinyi Tang,&nbsp;Yali Zhou,&nbsp;Xiaoyun Zhang,&nbsp;Hongyin Zhang","doi":"10.1016/j.ijfoodmicro.2025.111350","DOIUrl":"10.1016/j.ijfoodmicro.2025.111350","url":null,"abstract":"<div><div><em>Debaryomyces hansenii,</em> an antagonistic yeast, effectively suppresses postharvest pathogens in various across fruit and vegetable commodities. However, the specific mechanisms underlying its ability to trigger defense responses in pear fruits remain poorly understood. This study investigated the physiological and molecular mechanisms associated with <em>D. hansenii</em>-induced disease resistance in pear fruits. The results showed that <em>D. hansenii</em> significantly inhibited <em>Penicillium expansum</em>, rapidly colonized on wound and surfaces at 20 °C, and competitively excluded pathogens by monopolizing carbon sources and spatial niches. Physiological analyses revealed that <em>D. hansenii</em> enhanced the activity of resistance-related enzymes (Polyphenol oxidase, Phenylalanine ammonia-lyase, and Peroxidase) and increased secondary metabolite content (total phenols and flavonoids) while reducing Malondialdehyde (MDA) levels. Moreover, this yeast induced the activity of antioxidant enzymes (Superoxide dismutase, Catalase, and Ascorbate peroxidase) in pears, which synergistically scavenged reactive oxygen species (ROS) to maintain redox homeostasis. Transcriptomic analysis demonstrated that <em>D. hansenii</em> activates five key pathways, triggering the expression of genes involved in the biosynthesis of defense-related antimicrobial compounds. Additionally, it activates calcium signaling-MAPK-WRKY cascades, thereby upregulating defense-related genes such as <em>PR1</em>. Notably, critical genes (<em>AOS</em> and <em>OPR2</em>) in the jasmonic acid (JA) signaling pathway were significantly upregulated. This study is the first to elucidate the synergistic role of <em>D. hansenii</em> in enhancing postharvest disease resistance in pear fruits through multidimensional mechanisms. This study provides a theoretical foundation for the development of efficient and safe biocontrol technology.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111350"},"PeriodicalIF":5.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144656089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthetic microbial community mimicking kefir for investigating community dynamics and interspecies interactions","authors":"Tiantian Cheng ,&nbsp;Jinrong Zhao ,&nbsp;Tuo Zhang ,&nbsp;Genna Ba ,&nbsp;Qicheng Fan ,&nbsp;Yuanzheng Sun ,&nbsp;Guangfu Zhang ,&nbsp;Faizan Ahmed Sadiq ,&nbsp;Yaxin Sang ,&nbsp;Jie Gao","doi":"10.1016/j.ijfoodmicro.2025.111345","DOIUrl":"10.1016/j.ijfoodmicro.2025.111345","url":null,"abstract":"<div><div>Kefir grains serve as natural dairy starter cultures, surviving in high-altitude environments with low temperatures and limited oxygen, while maintaining robust fermentation capabilities. In this study, we reconstructed a synthetic microbial community (SMC) within the kefir microbial ecosystem and explored the strategies that keep this SMC stable and functioning within the complex environment. We investigated the interactions among kefir species by comparing their symbiotic capabilities, milk acidification properties, and fermentation profiles during growth in both individual cultures and co-cultures across various media. Additionally, to deepen our understanding of system-level responses within the SMC, we integrated metabolomics with pure culture techniques to elucidate the mechanisms that enable coexistence among SMC members. The composition of the SMC in fermented milk was determined through co-cultivation assessments and flavor profile analysis, which identified the key members as <em>Lactobacillus kefiranofaciens</em> CZ22, <em>Lactococcus lactis</em> CZ19, and <em>Saccharomyces cerevisiae</em> Y8. The fermented milk produced by SMC shared identical volatile compound profiles with traditional kefir milk, including seven alcohols, seven aldehydes, six ketones, five esters, two carboxylic acids, two ethers, one acyl compound, and five miscellaneous volatile compounds. Our findings revealed that the coexistence mechanism among these three species is based on cross-feeding interactions. <em>Lc. lactis</em> CZ19 provides <em>L. kefiranofaciens</em> CZ22 with amino acids such as tyrosine, proline, and arginine, promoting its growth. Moreover, <em>S. cerevisiae</em> Y8 supplies primary metabolic products, including purines, pyrimidines, and nucleotides, to <em>L. kefiranofaciens</em> CZ22, facilitating the coexistence of all three species. During the fermentation process of the SMC, <em>L. kefiranofaciens</em> CZ22 maintained high abundance and accelerated acidification and enhanced flavor volatiles in milk. The SMC we constructed effectively maintained the core kefir species and fermentation performance of kefir starter cultures, simplified the complex fermentation system and laid the groundwork for the modernization and improvement of the production process. This study systematically elucidates the coexistence strategies employed by synthetic microbial systems in fermented milk production, while enhancing our understanding of microbial interactions in traditional fermented foods.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"442 ","pages":"Article 111345"},"PeriodicalIF":5.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144656091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}