FOOD MICROBIOLOGY食品微生物学
FOOD MICROBIOLOGY(英文缩写 FOOD MICROBIOL),ISSN 0740-0020,eISSN 1095-9998,中文译名:食品微生物学 是一本学术期刊。本页汇总该期刊的最新影响因子、分区信息以及最新收录于 PubMed 的文献,帮助您快速了解期刊全貌。
发文量统计区间：2025-10-01 至 2026-09-30，按本站收录文献的发表日期统计。
期刊介绍
历年影响因子趋势
| JCR 数据年份 | 影响因子 | JCR 分区 |
|---|---|---|
| 2021 | 6.374 | Q1 |
| 2022 | 5.300 | Q1 |
| 2023 | 4.500 | Q1 |
| 2024 | 4.600 | Q1 |
| 2025 | 5.400 | Q1 |
FOOD MICROBIOLOGY 最新收录文献
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1. Antifungal mechanisms of volatile organic compounds and lactic acid produced by Lactiplantibacillus pentosus and their biocontrol application in fresh corn against Fusarium graminearum.
1. 戊糖乳杆菌产生的挥发性有机化合物和乳酸的抗真菌机制及其在新鲜玉米中对禾谷镰刀菌的生物防治应用PMID:日期:2026-08-18[中文摘要] 禾谷镰刀菌（Fusarium graminearum）会导致谷物腐败并产生真菌毒素。目前，生物防治微生物已成为一种安全且有前景的策略，用于控制谷物中产毒真菌的污染。本研究的主要目的是阐明分离得到的戊糖乳植物杆菌（Lactiplantibacillus pentosus）Q11对禾谷镰刀菌的抗真菌机制，并评估其无细胞上清液（CFS）在新鲜甜玉米中的防腐效果。戊糖乳植物杆菌Q11的体外抗真菌试验显示，其对禾谷镰刀菌、黄曲霉（Aspergillus flavus）和扩展青霉（Penicillium expansum）具有强拮抗活性，并具有降低玉米赤霉烯酮的能力。此外，全基因组分析未发现与毒力和抗菌药物耐药性相关的基因，且未观察到溶血活性，表明菌株Q11具有潜在安全性。此外，戊糖乳植物杆菌Q11的CFS有效抑制了禾谷镰刀菌的菌丝生长，破坏了菌丝完整性，并诱导真菌细胞死亡。同时，通过SPME-GC-MS和HPLC从Q11菌株的CFS中鉴定出3种有机酸和38种挥发性化合物，其中2-壬酮、2-甲基吡嗪、乳酸和乙酸为主要化合物。CFS及乳酸与2-壬酮联合处理严重破坏了禾谷镰刀菌的菌丝，通过破坏细胞膜和细胞壁导致细胞内物质泄漏，显示出这两种关键化合物的协同抗真菌效应。随后，与对照组相比，CFS及联合处理组在新鲜甜玉米贮藏12天后，显著降低了88.05%–89.52%的真菌种群数量以及AFB和DON真菌毒素的积累。处理组玉米中丙二醛含量降低了29.25%–31.50%，与POD和APX活性升高相一致，从而保持了其感官特性和营养品质。代谢组学分析显示，处理组玉米谷胱甘肽代谢通路中L-谷氨酸、γ-谷氨酰半胱氨酸和氧化型谷胱甘肽显著下调，表明含有乳酸和2-壬酮的CFS能够抑制真菌生长并缓解新鲜甜玉米中的氧化应激。总体而言，这些研究结果表明，具有协同挥发性有机化合物和乳酸的戊糖乳植物杆菌Q11是一种有前景的生物防治剂，可用于新鲜甜玉米的保鲜。
[英文摘要] Fusarium graminearum causes cereal spoilage and mycotoxin production. Currently, biocontrol microorganisms have emerged as a safe and promising strategy to manage the contamination of toxin-producing fungi in cereal grains. The primary objective was to elucidate the antifungal mechanism of an isolated strain of Lactiplantibacillus pentosus Q11 against F. graminearum and to evaluate the preservative effects of its cell-free supernatant (CFS) in fresh sweet corn. In vitro antifungal assays of L. pentosus Q11 showed strong antagonistic activity against F. graminearum, Aspergillus flavus, and Penicillium expansum, as well as the ability to reduce zearalenone. Moreover, whole-genome analysis revealed no genes related to virulence and antimicrobial resistance, and no hemolytic activity was observed, which suggested the potential safety of strain Q11. Moreover, the CFS of L. pentosus Q11 effectively inhibited the mycelial growth of F. graminearum, disrupted hyphal integrity, and induced fungal cell death. Moreover, 3 organic acids and 38 volatile compounds in the CFS of Q11 strain were identified by SPME-GC-MS and HPLC, in which 2-nonanone, 2-methylpyrazine, lactic acid, acetic acid were predominant compounds. The CFS and lactic acid combined with 2-nonanone severely damaged hyphae of F. graminearum, by disrupting cell membrane and wall, leading to leakage of intracellular substances, showing a synergistic antifungal effect of the two vital compounds. Subsequently, the treatments of CFS and combined agents significantly decreased 88.05% - 89.52% of fungal populations, and AFB and DON mycotoxin accumulation in fresh sweet corn after 12 days of storage compared to the control. The malondialdehyde content in the treated corn was decreased by 29.25% - 31.50%, consistent with the higher activities of POD and APX, thereby preserving their sensory attributes and nutritional quality. Metabolomic analysis revealed that L-glutamate, γ-glutamylcysteine, and oxidized glutathione were significantly downregulated in the glutathione metabolism pathway in the treated corn, indicating that CFS containing lactic acid and 2-nonanone could repress fungal growth and alleviate oxidative stress in fresh sweet corn. Overall, these findings demonstrate that L. pentosus Q11 with synergistic volatile organic compounds and lactic acid is a promising biocontrol agent in preserving fresh sweet corn.
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2. Microbial succession is linked to phenylpropanoid remodeling, aroma softening, and quality improvement in naturally aged Artemisia argyi leaves.
2. 微生物演替与自然陈化艾叶中苯丙素类重塑、香气软化及品质提升相关PMID:日期:2026-08-18[中文摘要] 艾叶是一种在东亚广泛使用的食用、药用和芳香植物，其叶片传统上在采收后经过陈化以提高品质。然而，这一做法的化学和微生物基础仍不清楚。本研究采用气相色谱-质谱联用（GC-MS）、靶向代谢组学、微生物扩增子测序、生物活性测定及基于菌株的发酵验证，对三年自然采后陈化过程中的代谢重塑、微生物演替、品质形成及微生物转化潜力进行了研究。陈化逐步重塑了挥发性和非挥发性代谢物，并增强了生物活性，使ABTS清除活性提高至67.41%，并将抗金黄色葡萄球菌的最低抑菌浓度（MIC）从25 mg/mL降至6.25 mg/mL。辛辣的含氮、含硫及萜烯相关挥发性成分持续下降，表现为1-壬烯-3-酮的相对气味活性值（rOAV）贡献从8.69%降至0.58%，而22种上调的C15挥发性成分中有21种为含氧衍生物，有助于香气柔和化。苯丙烷代谢网络呈现阶段依赖性转变，其特征为绿原酸耗竭、咖啡酸短暂积累以及下游衍生物（包括阿魏酸、松柏苷和芥子酰基相关缀合物）的富集。这些化学变化与微生物演替密切平行，其中假单胞菌属、鞘氨醇单胞菌属、泛菌属和气微菌属优先与咖啡酸相关代谢物关联。基于菌株的验证进一步表明，所选可培养分离株能够降解绿原酸，且P-A1-3促进了咖啡酸积累。总之，这些发现表明艾叶陈化是一个活跃的成熟过程，涉及微生物演替、苯丙烷重塑、香气柔和化及功能增强。
[英文摘要] Artemisia argyi is an edible, medicinal, and aromatic plant widely used in East Asia, whose leaves are traditionally aged after harvest to improve quality. However, the chemical and microbial basis of this practice remains unclear. Here, we investigated metabolic remodeling, microbial succession, quality formation, and microbial transformation potential during three years of natural postharvest aging using GC-MS, targeted metabolomics, microbial amplicon sequencing, bioactivity assays, and strain-based fermentation validation. Aging progressively reshaped volatile and nonvolatile metabolites and enhanced bioactivities, increasing ABTS scavenging activity to 67.41% and lowering the MIC against Staphylococcus aureus from 25 to 6.25 mg/mL. Pungent nitrogen-, sulfur-, and terpene-related volatiles declined continuously, as reflected by the decrease in the rOAV contribution of 1-nonen-3-one from 8.69% to 0.58%, whereas 21 of the 22 upregulated C15 volatiles were oxygenated derivatives, contributing to aroma softening. The phenylpropanoid network showed a stage-dependent transition characterized by chlorogenic acid depletion, transient caffeic acid accumulation, and enrichment of downstream derivatives, including ferulic acid, coniferin, and sinapoyl-related conjugates. These chemical changes closely paralleled microbial succession, with Pseudomonas, Sphingomonas, Pantoea, and Aeromicrobium preferentially associated with caffeic acid-related metabolites. Strain-based validation further showed that selected culturable isolates could degrade chlorogenic acid, and P-A1-3 promoted caffeic acid accumulation. Together, these findings indicate that AAL aging is an active maturation process involving microbial succession, phenylpropanoid remodeling, aroma softening, and functional enhancement.
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3. Correlation between microbial communities, metabolites, and bioactivities in fermented mare's milk revealed by metagenomics and metabolomics.
3. 宏基因组学和代谢组学揭示了发酵马奶中微生物群落、代谢物和生物活性之间的相关性PMID:日期:2026-08-17[中文摘要] 马奶酒具有抗氧化、降血糖和降血压等多种功能特性；然而，自然发酵存在微生物群落结构不可控、产品质量波动大以及缺乏专用发酵剂等问题。自然发酵与接种发酵体系中微生物群落、功能性代谢物与生物活性之间关联的机制尚不清楚。因此，本研究采用生物活性测定、宏基因组学和非靶向代谢组学，系统分析了不同发酵方式下马奶的微生物群落、代谢物组成和功能活性的差异。结果表明，与自然发酵相比，混合乳酸菌（LAB）接种发酵显著增强了马奶的抗氧化、α-葡萄糖苷酶抑制、α-淀粉酶抑制活性以及ACE抑制活性；发酵样品的微生物多样性显著降低，其中接种组的降低更为明显。代谢组学分析表明，接种发酵显著富集了脂质和有机酸等功能性代谢物。相关性分析表明，Lactiplantibacillus和Limosilactobacillus的丰度与有益代谢物（如亚油酸、α-亚麻酸）及功能活性呈显著正相关。脂质和氨基酸代谢途径与接种发酵马奶体外生物活性的差异密切相关。本研究提供了一种能够提高马奶体外功能活性的发酵剂，揭示了乳酸菌发酵与马奶功能特性改变之间潜在的代谢联系，从而为高附加值发酵马奶产品的开发提供了理论依据和技术支持。
[英文摘要] Koumiss exhibits various functional properties, including antioxidant, hypoglycemic, and antihypertensive effects; however, natural fermentation is characterized by an uncontrollable microbial community structure, significant fluctuations in product quality, and a lack of specialized fermentation agents. The mechanisms underlying the links between microbial communities, functional metabolites, and bioactivity in natural and inoculated fermentation systems remain unclear. Therefore, this study employed bioactivity assays, metagenomics, and non-targeted metabolomics to systematically analyze differences in microbial communities, metabolite composition, and functional activities of mare's milk under different fermentation regimes. The results indicated that, compared with natural fermentation, inoculated fermentation with a mixed lactic acid bacteria (LAB) culture significantly enhanced the antioxidant, α-glucosidase, α-amylase inhibitory activities, and ACE inhibitory activity of mare's milk; microbial diversity in fermented samples was significantly reduced, with a more pronounced decrease in the inoculated group. Metabolomic analysis revealed that inoculated fermentation significantly enriched functional metabolites, including lipids and organic acids. Correlation analysis indicated that the abundance of Lactiplantibacillus and Limosilactobacillus was significantly positively correlated with beneficial metabolites (e.g., linoleic acid, α-linolenic acid) and functional activities. The lipid and amino acid metabolic pathways are closely associated with the differences in in vitro biological activity of inoculated fermented mare's milk. This study provides a fermentation starter that can improve the in vitro functional activity of mare's milk and reveals the potential metabolic links between LAB fermentation and the altered functional traits of mare's milk, thereby providing a theoretical basis and technical support for the development of high-value-added fermented mare's milk products.
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4. Lactate-enhanced production of a cyclic β-1,2-glucan in Acetobacter pasteurianus.
PMID:日期:2026-08-17Cyclic β-1,2-glucans (CβGs) are well documented in pathogenic and plant-associated α-proteobacteria, but their occurrence in food-relevant acetic acid bacteria (AAB) remains poorly understood. Here, we report a neutral CβG, designated CG-I, in the vinegar-fermenting strain Acetobacter pasteurianus CICC 22518. CG-I production increased under lactate supplementation. MALDI-TOF/MS, accurate-mass high-resolution ESI-MS, and reducing-end analysis are consistent with a cyclic topology and exclude a predominantly linear glucan structure. FTIR spectroscopy and ESI-CID-MS/MS indicate a β-configured, 1→2-linked glucan backbone, with dominant species observed at a degree of polymerization (DP) of 24-26. Lactate supplementation (5.0 g/L) increased CG-I production to approximately 10.4 mg/g dry cell weight, compared with 1.39 and 0.71 mg/g under ethanol and glucose conditions, respectively. This increase was accompanied by elevated expression of cgs (FCN51_RS25580), and deletion of cgs abolished detectable CG-I production. The Δcgs mutant showed reduced motility and growth under elevated lactate concentrations but no detectable defect in maximal biomass under the tested hypoosmotic conditions. CG-I was also detected in simulated grain vinegar fermentation. Together, these findings identify a CβG in a food-relevant AAB and support a link between lactate-rich conditions and increased cgs expression and CG-I production.
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5. From intervention priority to microbiological risk: interpreting Fuzzy-FMEA in household food safety.
5. 从干预优先到微生物风险：解读家庭食品安全中的模糊失效模式与影响分析PMID:日期:2026-08-16[中文摘要] Zhang等提出了一种创新的模糊失效模式与影响分析框架，通过整合全国调查数据与结构化专家 elicitation，对中国家庭食品处理行为进行优先级排序。尽管该方法为靶向食品安全干预提供了务实基础，但对所得模糊风险优先数的解读需谨慎。发生度估计源自异质性且有时为条件性分母的行为条目，限制了失效模式之间的直接可比性。此外，将检测度重新定义为消费者风险意识引入了一个可能与发生度相关的构念，造成模型维度之间的潜在重叠。因此，我们建议将这些排序主要解读为行为干预和风险沟通的优先事项，而非微生物学疾病风险的直接估计。将行为频率与病原体特异性暴露数据及定量微生物风险评估相结合，可进一步加强未来的优先级排序框架。
[英文摘要] Zhang et al. proposed an innovative Fuzzy Failure Mode and Effect Analysis framework to prioritize household food-handling practices in China by integrating national survey data with structured expert elicitation. Although this approach offers a pragmatic basis for targeting food-safety interventions, the interpretation of the resulting fuzzy risk priority numbers warrants caution. Occurrence estimates were derived from behavioral items with heterogeneous and sometimes conditional denominators, limiting direct comparability across failure modes. In addition, redefining detection as consumer risk awareness introduces a construct that may be related to occurrence, creating potential overlap between model dimensions. We therefore suggest interpreting the rankings primarily as priorities for behavioral intervention and risk communication rather than as direct estimates of microbiological disease risk. Integrating behavioral frequency with pathogen-specific exposure data and quantitative microbiological risk assessment could further strengthen future prioritization frameworks.
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6. Control of Alicyclobacillus acidoterrestris spore and Byssochlamys ascospore growth in ambient acid dairy products through organic acid and heat treatments.
6. 通过有机酸和热处理控制常温酸性乳制品中酸土脂环酸芽孢杆菌孢子及丝衣霉子囊孢子的生长PMID:日期:2026-08-14[中文摘要] 产芽孢微生物在常温酸性乳基产品中构成显著的腐败风险。本研究探讨了有机酸与热处理在常温酸性乳制品相关条件（pH 4.6）下对酸土脂环酸芽孢杆菌（Alicyclobacillus acidoterrestris）芽孢和丝衣霉（Byssochlamys）子囊孢子的单独及联合控制效果。在所测试的有机酸中，山梨酸钾（Potassium Sorbate，PS）表现出第二高的抗菌效力，对酸土脂环酸芽孢杆菌的最低抑菌浓度（MIC）为0.8–1.6 mg/mL，对丝衣霉属为0.8 mg/mL。在肉汤中，PS ≥ 0.5 mg/mL单独使用或与本研究中所用的任一热处理联合使用，均能在25 °C和40 °C下有效控制酸土脂环酸芽孢杆菌芽孢的萌发。控制丝衣霉子囊孢子方面，在25 °C贮藏时，需单独使用0.8 mg/mL PS，或0.5 mg/mL PS联合热处理（85 °C 10 min）或热处理（95 °C 30 s）；而在40 °C贮藏时，单独使用PS（0.5 mg/mL或0.8 mg/mL）或单独热处理（95 °C 30 s）即可。在饮用酸奶中的验证证实，单独使用PS（0.5 mg/mL或0.8 mg/mL）可防止酸土脂环酸芽孢杆菌在40 °C下萌发，而仅0.8 mg/mL PS联合75 °C 20 min热处理才能在酸奶于40 °C贮藏12周的条件下完全抑制黄丝衣霉（B. fulva）子囊孢子。这些研究结果为确保常温酸性乳制品对抗耐热腐败微生物的微生物稳定性提供了一种实用的多靶栅栏策略。
[英文摘要] Spore-forming microorganisms pose a significant spoilage risk in ambient acid dairy-based products. This study investigated the individual and combined effects of organic acids and heat treatments on controlling Alicyclobacillus acidoterrestris spores and Byssochlamys ascospores under conditions relevant to ambient acid dairy products (pH 4.6). Potassium Sorbate (PS) demonstrated the second highest antimicrobial efficacy among the tested organic acids, with MICs of 0.8-1.6 mg/mL against A. acidoterrestris and 0.8 mg/mL against Byssochlamys species. In broth, PS ≥ 0.5 mg/mL alone or combined with any of the heat treatments used in this study effectively controlled A. acidoterrestris spore outgrowth at 25 °C and 40 °C. Control of Byssochlamys ascospores required 0.8 mg/mL PS alone or 0.5 mg/mL PS combined with heat (85 °C for 10 min) or heat (95 °C for 30 s) when stored at 25 °C; but when storing at 40 °C, PS (0.5 mg/mL or 0.8 mg/mL) alone or heat treatment (95 °C for 30 s) alone was sufficient. Validation in drinking yoghurt confirmed that PS alone (0.5 mg/mL or 0.8 mg/mL) prevented A. acidoterrestris outgrowth at 40 °C, while only 0.8 mg/mL PS combined with 75 °C for 20 min heat treatment achieved complete inhibition of B. fulva ascospores when yoghurt was stored at 40 °C over 12 weeks. These findings provide a practical multi-hurdle strategy for ensuring the microbiological stability of ambient acid dairy products against heat-resistant spoilage organisms.
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7. Nationwide surveillance of pESI-positive Salmonella Infantis ST32 in South Korea: Endemic establishment of a dominant lineage across the broiler production chain, 2020-2023.
7. 韩国全国范围内pESI阳性婴儿沙门氏菌ST32的监测：2020-2023年优势谱系在肉鸡生产链中的地方性定植PMID:日期:2026-08-14[中文摘要] 自2020年以来，韩国出现了携带pESI样巨型质粒的多重耐药（MDR）婴儿沙门氏菌ST32的快速增加。我们通过对主要肉鸡屠宰场开展为期四年的全国性监测，调查了这一现象背后的驱动因素。对从鸡粪（n=29）和胴体（n=28）中获得的57株分离株进行高分辨率核心基因组多位点序列分型（cgMLST），鉴定出三个不同的谱系（分支I、II和III）。进一步利用最小生成树进行比较分析，并纳入来自公共数据库的额外人类临床分离株（n=6）和零售肉类分离株（n=46），揭示了“粪便-胴体-零售-人类”连续体之间更广泛的遗传关系。其中，分支III成为优势地方性流行谱系，持续在14个生产网络中循环传播，并维持从农场层面粪便到零售肉类的强遗传联系。值得注意的是，基因组分析证实98.6%的分离株携带bla阳性pESI样巨型质粒，且全部57株分离株（100%）表现出高度保守的核心染色体毒力因子谱（如SPI-1、SPI-2和fim操纵子）。主要分支（I-III）表现出高接合转移能力（>80%），而非分支分离株的质粒传播能力显著较低，提示水平转移效率是克隆优势的关键决定因素。尽管禽源分支与所采样的人类临床分离株在遗传上仍存在差异，但其在全国食品供应链中的结构性巩固表明，这是一个具有引起人类感染潜力的强大MDR储存库。这些发现为pESI阳性谱系的持续存在提供了全面的基因组-流行病学框架，强调需要开展有针对性的、谱系特异性监测以降低公共卫生风险。
[英文摘要] Since 2020, South Korea has seen a rapid surge in multidrug-resistant (MDR) Salmonella Infantis ST32 harboring pESI-like megaplasmids. We investigated the driving forces behind this emergence through a nationwide, four-year surveillance of major broiler slaughterhouses. High-resolution core-genome multi-locus sequence typing (cgMLST) of 57 isolates obtained from chicken feces (n = 29) and carcasses (n = 28) identified three distinct lineages (clades I, II, and III). Further comparative analysis using a minimum spanning tree, incorporating additional human (n = 6) clinical and retail meat (n = 46) isolates from public databases, revealed the broader genetic relationships across the "feces-carcass-retail-human" continuum. Among these, clade III emerged as the dominant endemic lineage, persistently circulating across 14 production networks and maintaining strong genetic linkage from farm-level feces to retail meat. Notably, genomic analysis confirmed that 98.6% of isolates carried bla-positive pESI-like megaplasmids, and all 57 isolates (100%) exhibited a highly conserved profile of core chromosomal virulence factors (e.g., SPI-1, SPI-2, and fim operon). Major clades (I-III) exhibited high conjugative transferability (>80%), while non-clade isolates showed significantly lower plasmid transmissibility, suggesting that horizontal transfer efficiency is a key determinant of clonal dominance. Although poultry-derived clades remained genetically divergent from the sampled human clinical isolates, their structural consolidation within the national food supply signifies a robust MDR reservoir with the potential to cause human infection. These findings provide a comprehensive genomic-epidemiological framework for the persistence of pESI-positive lineages, emphasizing the need for targeted, lineage-specific surveillance to mitigate public health risks.
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8. CRISPR-Cas9 mediated adiA knockout in Hafnia paralvei: Implications for agmatine production and acid stress survival in a fermented dairy matrix.
8. CRISPR-Cas9介导的副蜂房哈夫尼菌adiA基因敲除：对发酵乳基质中胍丁胺产生及酸胁迫存活的影响PMID:日期:2026-08-14[中文摘要] 胍丁胺（agmatine）是精氨酸在精氨酸脱羧酶（arginine decarboxylase，ADC）催化下脱羧的产物，是一种具有生物活性的化合物，作为神经调质和共递质发挥功能，近年来因其治疗潜力，尤其是神经保护特性而受到越来越多的关注。哈夫尼菌属（Hafnia）成员是乳制品中主要的胍丁胺产生菌。在此背景下，哈夫尼菌被认为是一种有益微生物，因为它能够改善奶酪的感官特性，并具有新兴的益生菌潜力，使其与功能性食品开发相关，尤其是富含胍丁胺的乳制品。本研究旨在鉴定副哈夫尼菌（Hafnia paralvei）中胍丁胺产生的遗传基础，并评估其在细菌适应性中的作用。对副哈夫尼菌IPLA15029菌株的基因组分析揭示了两个编码推定ADC酶的基因，adiA和speA，但其组织方式与其他肠杆菌略有不同。在一些细菌中，ADC以两种形式存在：一种参与多胺生物合成，由组成型speA基因编码；另一种参与酸胁迫抗性，由adiA基因编码，该基因在酸性条件下可诱导表达。在受控pH条件下的体内实验表明，胍丁胺的积累仅发生在酸性条件下，酸性条件还通过阻止其分解为腐胺来稳定该化合物。基因表达分析显示，adiA以单顺反子单位转录，且在这些条件下，adiA是负责胍丁胺产生的基因。这一点通过实施CRISPR-Cas9系统后生成adiA敲除突变体得到证实，标志着该技术首次在哈夫尼菌属中成功应用。此外，adiA敲除表明，所编码的精氨酸脱羧酶对于在严重酸胁迫下存活至关重要。
[英文摘要] Agmatine, the product of the decarboxylation of arginine, catalysed by arginine decarboxylase (ADC), is a bioactive compound that functions as a neuromodulator and co-transmitter and has gained increasing attention in recent years due to its therapeutic potential, particularly for its neuroprotective properties. Members of the genus Hafnia are the main agmatine producers in dairy products. In this regard, Hafnia is considered a beneficial microorganism due to its ability to enhance cheese organoleptic properties and its emerging probiotic potential, making it relevant for functional food development, specially agmatine-enriched dairy products. This study aimed to identify the genetic basis for agmatine production in Hafnia paralvei and to assess its role in bacterial fitness. Genomic analysis of the strain H. paralvei IPLA15029 revealed the presence of two genes encoding putative ADC enzymes, adiA and speA, however, organized slightly different than those in other enterobacteria. In some bacteria, ADC exists in two forms: one involved in polyamine biosynthesis, encoded by the constitutive speA gene, and another involved in acid stress resistance, encoded by the adiA gene, which is inducible under acidic conditions. In vivo experiments under controlled pH conditions showed that agmatine accumulation occurs exclusively under acidic conditions, which also stabilize the compound by preventing its catabolism to putrescine. Gene expression analysis revealed that adiA was transcribed as a monocistronic unit, and that in these conditions, adiA is the gene responsible for agmatine production. This was confirmed by generating an adiA knockout mutant after the implementation of the CRISPR-Cas9 system, marking the first successful application of this technology in the genus Hafnia. Moreover, the adiA knockout demonstrated that the encoded arginine decarboxylase is essential for survival under severe acid stress.
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9. Multi-omics integration deciphered microbial and metabolite dynamics during flavor development of probiotic-fermented Gastrodia elata Blume.
PMID:日期:2026-08-14This study examined the succession of metabolites and microorganisms during the fermentation of Gastrodia elata Blume (GE) and their interrelationships. A total of 739 volatile compounds (VCs) were identified, with four recognized as key VCs: dimethyl disulfide, dimethyl trisulfide, 2-nonenal, and damascenone. The dominant bacteria in the prime fermentation liquid (PFL) and secondary fermentation liquid (SFL) stages exhibited dynamic changes influenced by total acid, total polyphenols, total flavonoids, and pH, with Limosilactobacillus and Acetobacter emerging as the predominant bacteria, respectively, in these stages compared to the GE water extract (WGE) stage. Metabolomics analysis revealed that 16 metabolites were associated with chemical structure transformation maps pathways (nucleotide metabolism, biosynthesis of plant secondary metabolites) and metabolism of cofactors and vitamins (folate biosynthesis). This research provides a theoretical foundation for regulating specific flavors in GE.
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10. Strain-level identification and quantitative detection of Lactiplantibacillus plantarum in fermented milk using MALDI-TOF MS.
PMID:日期:2026-08-14The efficacy of probiotics is highly strain-specific; however, accurate strain-level identification remains challenging. In this study, Lactiplantibacillus plantarum, a species widely used in probiotic products, was selected as the target organism to develop a strain-level identification method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). First, comparative analysis of ribosomal protein sequences from 11 strains revealed significant interstrain variation in both number and sequence, theoretically supporting the feasibility of MALDI-TOF MS for strain discrimination. Subsequently, an orthogonal experimental design was employed to optimize the formic acid extraction method. The optimal conditions were harvesting 1000 μL of decline-phase culture, extraction with 75% FA, and a formic acid-to-acetonitrile volume ratio of 80:80 (v/v). By evaluating the number, relative intensity, and positional variation of characteristic peaks within the main spectrum profiles, the optimal number of raw spectra required to construct a single-strain database was determined to be 10. Based on these optimized parameters, a MALDI-TOF MS database for L. plantarum, designated as YLp10-2025, was successfully established. Using this database, individual identification and accurate quantitative detection of different L. plantarum strains were achieved in commercially available fermented milk artificially inoculated with these strains. The strain identification approach established in this study, based on an external MALDI-TOF MS database, provides an effective tool for evaluating the quality of probiotic products and offers technical support for developing strain-level identification methods for other microorganisms.