MicrobiologyOpen最新文献

{"title":"Biofilm Formation on Endotracheal and Tracheostomy Tubing: A Systematic Review and Meta-Analysis of Culture Data and Sampling Method","authors":"Ed Deshmukh-Reeves,&nbsp;Matthew Shaw,&nbsp;Charlotte Bilsby,&nbsp;Campbell W. Gourlay","doi":"10.1002/mbo3.70032","DOIUrl":"https://doi.org/10.1002/mbo3.70032","url":null,"abstract":"<p>Biofilm formation on tracheal tubing is a key risk factor for ventilator-associated pneumonia. Endotracheal tube microbiology has been systematically reviewed, but tracheostomy tube profiles have not. Analysis of the tube-associated microbiome is not standardised, and sampling methods are varied. We compared the reported microbiomes of endotracheal and tracheostomy tubes and examined the impact of sampling by tracheal aspiration or direct culture. We searched PubMed, SCOPUS, and Web of Knowledge for clinical microbiology studies from 2000–2024, extracting tubing type, sampling method, and the most prevalent genera identified. Genera were compared by Spearman's rank correlation and pairwise analyses by Šidák's test. Extraction from 49 studies identified 30 genera. <i>Pseudomonas</i> was the most prevalent in all conditions followed by <i>Klebsiella, Staphylococcus</i>, and <i>Acinetobacter</i>. 25 studies performed tracheal aspiration, and 22, direct culture. Two studies used both methods. Correlation was observed between endotracheal and tracheostomy tubes, and aspirates and direct cultures (Spearman's rho = 0.69; 0.59). <i>Pseudomonas</i> were more prevalent in tracheostomy tubes (<i>p</i> &lt; 0.0001). Coagulase-positive <i>Staphylococci</i> were more common in tracheal aspirates, and coagulase-negative <i>Staphylococci</i> in direct culture. The microbial profiles of endotracheal and tracheostomy tubes are comparable, with <i>Pseudomonas</i> being the most common coloniser. Our analyses suggest that tracheal aspiration can effectively identify the constituents of biofilms without requiring tube removal, making it a valuable tool for clinical researchers to analyse or monitor biofilms before extubation or device failure using existing microbiology procedures.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70032","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of Medium Composition for High Cell Density Culture of Bifidobacterium longum HSBL001 Using Response Surface Methodology","authors":"Hao Cheng,&nbsp;Jiangbin Liu,&nbsp;Liya Mei,&nbsp;Wei Liu,&nbsp;Fengxi Yang,&nbsp;Xiaojuan Ma,&nbsp;Yan Zhang,&nbsp;Youfa Xie,&nbsp;Yang Zhang,&nbsp;Yanxia Xiong","doi":"10.1002/mbo3.70027","DOIUrl":"https://doi.org/10.1002/mbo3.70027","url":null,"abstract":"<p><i>Bifidobacterium longum</i> plays a critical role in the human gut and exhibits diverse probiotic functions. Achieving high-density fermentation of <i>B. longum</i> largely depends on the composition of the culture medium and fermentation conditions. This study aimed to optimize the medium composition and fermentation parameters for <i>B. longum</i> HSBL001, using viable cell counts and optical density at 600 nm (OD600) as indicators. The goal was to improve biomass yield and support the development and industrial application of highly active probiotic preparations. The optimal medium composition and culture conditions were established using a combination of single-factor experiments, the Plackett–Burman design, the steepest ascent method, and the central composite design. The optimized culture medium consisted of yeast extract (19.524 g/L), yeast peptone (25.85 g/L), arginine (0.599 g/L), glucose (27.36 g/L), MnSO₄ (0.09 g/L), MgSO₄ (0.8 g/L), Tween-80 (1 g/L), <span>l</span>-cysteine hydrochloride (0.24 g/L), and methionine (0.15 g/L). The optimal culture conditions included an initial pH of 7.0, 5% inoculum size, and incubation at 37°C, yielding a final viable cell count of 4.20 × 10⁹ colony-forming units (CFU/mL). In a 3 L bioreactor, the viable cell count reached 1.17 × 10¹⁰ CFU/mL, which was 1.786 times higher than that achieved with the modified MRS medium. These findings demonstrate that the optimized medium and fermentation conditions are well-suited for high-density cultivation of <i>B. longum</i> HSBL001 and provide a basis for its industrial application.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70027","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shaping Plant Growth Beneath the Soil: A Theoretical Exploration of Fungal Endophyte's Role as Plant Growth-Promoting Agents","authors":"Riyaz Ahmad Rather","doi":"10.1002/mbo3.70026","DOIUrl":"https://doi.org/10.1002/mbo3.70026","url":null,"abstract":"<p>Plant growth relies on both natural and agrochemical inputs, with natural soil nutrients and chemically synthesized fertilizers enhancing its growth. However, continuous fertilizer use can lead to soil alkalinity and environmental contamination, emphasizing the need for sustainable practices. Microbial agents, particularly fungal endophytes, have emerged as promising natural alternatives. They are recognized as integral components of the plant microbiome and aid in nutrient acquisition, hormone production, and stress resistance. Fungal endophytes enhance nutrient uptake by solubilizing phosphorus, fixing nitrogen, and producing siderophores that chelate iron. They also modulate plant hormones, including auxins, gibberellins, and cytokinins, promoting growth and development. Under abiotic stress, these endophytes improve plant tolerance by inducing systemic resistance and enhancing water and nutrient absorption. This review provides a comprehensive theoretical exploration of the role of fungal endophytes in promoting plant growth, examining their diversity, mechanisms of action, and practical applications. The focus is on understanding how these symbiotic organisms can be harnessed to enhance sustainable agricultural practices and contribute to environmental conservation.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70026","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel Animal Model of Enterobacteria Pathogenicity, Virulence, and Amoxicillin—Biosurfactant Synergic Using Nsombé (Rhynchophorus phoenicis Larvae)","authors":"Sergy Patrick Junior Bissoko,&nbsp;Christian Aimé Kayath,&nbsp;Saturnin Nicaise Mokemiabeka,&nbsp;Frédéric Yannick Okouakoua,&nbsp;David Charles Roland Moukala,&nbsp;Duchel Jeanedvi Kinouani Kinavouidi","doi":"10.1002/mbo3.70025","DOIUrl":"https://doi.org/10.1002/mbo3.70025","url":null,"abstract":"<p>Insect larvae are increasingly being employed as sophisticated infection models in the expanding field of pathogenic bacterial research. This innovative study aims to evaluate an alternative model for analyzing host-pathogen interactions and assessing the efficacy of antimicrobial treatments using the biological system of <i>Rhynchophorus phoenicis</i> larvae. Using PCR techniques targeting 16S rRNA, virulence genes encoding Type III secretion system (T3SS) components, and the <i>Hsp60</i> gene, four major pathogenic Enterobacteriaceae were identified with 100% detection rates: <i>Salmonella Typhimurium</i>, <i>Klebsiella pneumoniae</i>, <i>Enterobacter cloacae</i>, and enteropathogenic <i>Escherichia coli</i> (EPEC). Virulence assessment revealed that injection of bacterial strains at a concentration of 10⁵ CFU/µL into <i>R. phoenicis</i> larvae was optimal for evaluating pathogenicity. Highly virulent strains—<i>E. coli</i> EPEC strain E2, <i>K. pneumoniae</i> K4, <i>S. Typhimurium</i> S4, and <i>E. cloacae</i> En2—caused significantly reduced larval survival, with bacterial loads in the hemolymph reaching up to 2.5 × 10⁶ CFU/µL. Treatment evaluation showed that the amoxicillin + biosurfactant combination was the most effective in prolonging larval survival across all time points. Survival rates peaked at 80% at 24 h and remained relatively high at up to 70% at 72 h for certain strains. In contrast, amoxicillin alone demonstrated variable and less sustained efficacy. These findings underscore the potential of <i>R. phoenicis</i> larvae as a valuable alternative model for exploring host–pathogen interactions and assessing the synergistic efficacy of combined antimicrobial treatments involving antibiotics and biosurfactants.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70025","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144520140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genotypic Analysis of Candida tropicalis Clinical Isolates From Korea via Multilocus Sequence Typing","authors":"Hye-won Park,&nbsp;Lia Kim,&nbsp;Yoon-Sung Choi,&nbsp;Jinyoung Bae,&nbsp;Min-Ho Yeo,&nbsp;Eun Ju Lee,&nbsp;Jiyoung Lee,&nbsp;Kwangmin Park,&nbsp;Dong Geon Lee,&nbsp;Min Park,&nbsp;Sunghyun Kim,&nbsp;Jungho Kim","doi":"10.1002/mbo3.70024","DOIUrl":"https://doi.org/10.1002/mbo3.70024","url":null,"abstract":"<p><i>Candida tropicalis</i> is a clinically significant non-albicans species that has shown increasing azole resistance globally. Despite its growing clinical importance, genotypic and epidemiological data from East Asia, particularly Korea, remain limited. This study aimed to expand the global understanding of <i>C. tropicalis</i> population structure by genotyping clinical isolates from Korea and identifying novel sequence types. Thirty-four clinical isolates collected from tertiary hospitals across Korea between 2012 and 2019 were analyzed using multilocus sequence typing (MLST) based on six housekeeping genes (ICL1, MDR1, SAPT2, SAPT4, XYR1, and ZWF1). A total of 21 diploid sequence types (DSTs) were identified, including three novel DSTs (1418, 1419, and 1420) not previously recorded in the MLST central database. Notably, DST844 (CTR-19 isolate) exhibited elevated minimum inhibitory concentration (MIC) to fluconazole, suggesting a potential novel resistance phenotype. Phylogenetic and goeBURST analyses revealed 11 distinct clonal complexes (CCs), some of which showed similarity to Chinese and Brazilian lineages, indicating cross-regional evolutionary links. These findings enhance the global MLST data set, provide new insights into the molecular epidemiology of <i>C. tropicalis</i> in Korea, and highlight the need for continued antifungal resistance surveillance, particularly for emerging DSTs.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70024","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Six Commercial and Noncommercial Colistin Resistance Diagnostics","authors":"Tumisho Mmatumelo Seipei Leshaba,&nbsp;Masego Mmatli,&nbsp;Nontombi Marylucy Mbelle,&nbsp;John Osei Sekyere","doi":"10.1002/mbo3.70029","DOIUrl":"https://doi.org/10.1002/mbo3.70029","url":null,"abstract":"<p>Resistance to colistin, a last-reserve antibiotic used for treating drug-resistant infections, is rising globally. We compared six commercial and in-house diagnostics—ComASP colistin, CHROMagar COL-APSE, rapid polymyxin NP (Nordmann/Poirel) test, Sensititre, MicroScan, and Vitek 2—against ISO-standard broth microdilution (BMD) using 142 Gram-negative isolates. The isolates (<i>Enterobacterales</i> = 110, <i>Acinetobacter baumannii</i> = 21, <i>Pseudomonas aeruginosa</i> = 11) underwent BMD and conventional multiplex PCR screening for <i>mcr-1</i>–<i>mcr-5</i>. Sensitivity, specificity, categorical agreement (CA), major error (ME), and very major error (VME) were calculated for each test. Vitek 2 and sensititre yielded the highest CA (≥ 98%) and the lowest VME (≤ 0.0%) across taxa. ComASP showed excellent performance for <i>A. baumannii</i> (100% sensitivity/specificity) but slightly lower CA for <i>P. aeruginosa</i> (73%). CHROMagar COL-APSE demonstrated acceptable sensitivity (92%) but low specificity (69%) in Enterobacterales. MicroScan had reduced specificity in <i>Enterobacterales</i> (87.80%). The CHROMAgar COL-<i>APSE</i> efficiently identified the species with their unique colours but was the least specific (68.63%), with the highest ME in <i>Enterobacterales</i>. The rapid NP test provided rapid results within 4 h but showed a relatively high VME (7.84%), despite maintaining an acceptable sensitivity (92.16%) and specificity (96.08%). For laboratories with automated platforms, Vitek 2 remains optimal for colistin MIC testing; Sensititre and ComASP are suitable low-cost BMD alternatives. The Rapid NP test provides a same-day screen, but confirmatory MIC testing is advised. CHROMagar COL-APSE should be used with a ≤ 1 CFU mL⁻¹ inoculum to minimise false resistance calls. Knowing the comparative performance of these different tests will assist in choosing the best test for every species, improving on efficient diagnosis and healthcare outcomes.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection and Characterization of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in Raw Seafood From the Coastal Area of Bangladesh","authors":"Zannatul Firdous,&nbsp;Md. Saiful Islam,&nbsp;Md. Ashek Ullah,&nbsp;Md. Liton Rana,&nbsp;Farhana Binte Ferdous,&nbsp;Al-Muksit Mohammad Taufiquer Rahman,&nbsp;Jayedul Hassan,&nbsp;Md. Tanvir Rahman","doi":"10.1002/mbo3.70023","DOIUrl":"https://doi.org/10.1002/mbo3.70023","url":null,"abstract":"<p>The emergence of antimicrobial resistance (AMR) and extended-spectrum beta-lactamase (ESBL)-producing <i>Escherichia coli</i> (ESBL-EC) in seafood represents a significant public health concern. In this study, we screened 102 raw seafood samples, comprising shrimp (<i>n</i> = 42), sea fish (<i>n</i> = 36), and crabs (<i>n</i> = 24), to detect ESBL-EC. <i>E. coli</i> was isolated and identified through culture-based methods, staining procedures, biochemical assays, and polymerase chain reaction (PCR) analysis. The AMR properties of <i>E. coli</i> isolates were evaluated using the disc diffusion test, while ESBL-EC was identified phenotypically through the double-disc synergy test and confirmed at the genetic level using PCR. PCR analysis revealed that 42.2% (43/102) of the samples were contaminated with <i>E. coli</i>, with sea fish showing the highest (<i>p</i> &lt; 0.05) prevalence (63.9%, 23/36), followed by crabs (37.5%, 9/24) and shrimp (26.2%, 11/42). All the isolates exhibited phenotypic resistance to ampicillin, followed by ceftazidime (95.3%), ciprofloxacin (55.8%), azithromycin (39.5%), cefotaxime (37.2%), and streptomycin (16.3%). Notably, 69.8% (30/43) of <i>E. coli</i> isolates exhibited phenotypically multidrug resistance. Moreover, 18.6% (8/43) of the isolates showed ESBL-producing characteristics, higher in shrimp than in sea fish and crabs. ESBL-related gene, <i>bla</i>_TEM, was detected in 75% (6/8), <i>bla</i>_SHV in 87.5% (7/8), and <i>bla</i>_CTX-M in 50% (4/8) of the ESBL-EC isolates. Regular surveillance of seafood for antimicrobial-resistant bacteria, particularly ESBL-producing strains, is recommended due to their potential public health implications.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70023","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144492760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Iron Deficiency on the Growth and Bioelectrical Profile of Different Gut Bacteria","authors":"Elisa Quarta,&nbsp;Marwane Bourqqia-Ramzi,&nbsp;David Muñoz-Rodriguez,&nbsp;María Teresa García-Esteban,&nbsp;Antonio Murciano-Cespedosa,&nbsp;Álvaro Mateos González,&nbsp;Francisco José Conejero-Meca,&nbsp;Juan Lombardo-Hernandez,&nbsp;Jesús Mansilla-Guardiola,&nbsp;Simona Baroni,&nbsp;Simonetta Geninatti Crich,&nbsp;Stefano Geuna,&nbsp;Luca Munaron,&nbsp;Deborah Chiabrando,&nbsp;Celia Herrera-Rincon","doi":"10.1002/mbo3.70015","DOIUrl":"https://doi.org/10.1002/mbo3.70015","url":null,"abstract":"<p>Scope: Iron deficiency (ID) is the most common nutritional deficiency worldwide, impacting gut bacteria's metabolism and cellular biochemistry, but its effects on the microbiota-gut-brain axis (MGB) are poorly understood. Early-life ID-related dysbiosis is linked to neurodevelopmental impairments like autism and attention deficit hyperactivity disorder. Studying ID's impact on bacterial signaling can guide interventions to target MGB in iron-deficient populations. This study examined the responses of <i>Escherichia coli</i> (<i>E. coli</i>) and <i>Limosilactobacillus reuteri</i> (<i>L. reuteri</i>) to in-vitro ID conditions using the iron chelator 2,2’-Bipyridyl (BP). Methods and Results: We assessed and modeled their growth and cultivability and explored their bioelectric profiles using the voltage-sensitive dye DiBAC4(3). Results showed differential responses: <i>L. reuteri</i>'s growth and cultivability were unaffected by BP, while <i>E. coli</i>'s growth rate and cultivability decreased under ID. Additionally, we created a deterministic mathematical model that demonstrated a decrease in the population's average reproduction rate in <i>E. coli</i> under ID. Only <i>E. coli</i> exhibited an altered bioelectric profile, marked by increased cell depolarization in ID conditions, which was largely rescued upon the addition of a saturating concentration of iron. Conclusion: These findings highlight specific bioelectrical responses in gut bacteria to ID. Understanding this variability is crucial for deciphering the microbiota's role in health and disease, particularly concerning nutritional iron imbalance and bacterial signaling in the MGB.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144190776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat Treatment and Storage of Frass From Black Soldier Fly Larvae and Yellow Mealworm Production: Compliance With EU Regulation on Microbiological Quality and Safety","authors":"Ann De Volder,&nbsp;Jeroen De Smet,&nbsp;Lotte Frooninckx,&nbsp;David Deruytter,&nbsp;Johan Ceusters,&nbsp;Dries Vandeweyer","doi":"10.1002/mbo3.70020","DOIUrl":"https://doi.org/10.1002/mbo3.70020","url":null,"abstract":"<p>Insect farming generates substantial amounts of frass, a nutrient-rich by-product with valorization potential as fertilizer/soil improver. Marketing is restricted by EU regulations, imposing a reference heat treatment for 1 h at 70°C to reduce the presence of potential pathogens. This study evaluated the impact of heat treatments (50 → 80°C for 15 → 90 min) on microbiological quality and safety of black soldier fly larvae (BSFL) and yellow mealworm (YM) frass, as well as microbial dynamics during storage, before and after reference treatment. Fresh frass showed high microbial counts, but <i>Salmonella</i> was absent. Untreated BSFL frass did not meet the EU criteria to allow use as fertilizer, while some YM frass samples did. Reference heat-treated BSFL and YM frass complied with the EU criteria. <i>Escherichia coli</i> counts were below the 1000 cfu/g limit, and <i>Salmonella</i> (even when inoculated before treatment) was absent. Only in BSFL frass, Enterococcaceae counts were sufficiently reduced. Milder treatments (temperatures &lt; 70°C and/or times &lt; 1 h) of BSFL frass induced similar reductions of <i>E. coli</i> and (inoculated) <i>Salmonella</i> but Enterococcaceae counts remained above 1000 cfu/g. In some YM frass samples (inoculated) <i>Salmonella</i> was still detected after milder treatment. Refrigerated (4°C) or ambient temperature (26°C–28°C) storage up to 2 weeks of fresh and heat-treated frass did not increase bacterial counts. To ensure frass microbiological safety whilst preserving quality and reducing costs, tailored treatments seem appropriate. This may be no, milder, or more severe treatment, depending on the microbial load (counts and species type).</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144171677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial Distortion? Impacts of Delayed Preservation on Microbiome Diversity and Composition in a Marine Invertebrate","authors":"Brenna Hutchings,&nbsp;Susanna López-Legentil,&nbsp;Lauren Stefaniak,&nbsp;Marie Nydam,&nbsp;Patrick M. Erwin","doi":"10.1002/mbo3.70019","DOIUrl":"https://doi.org/10.1002/mbo3.70019","url":null,"abstract":"<p>Field collections of marine invertebrates are often accompanied by delays in preservation, which may impact microbiome composition. Here, we tested the effects of delayed preservation and relaxation methods on microbiome diversity and composition in the colonial ascidian <i>Trididemnum solidum</i> using 16S rRNA amplicon sequencing. Replicate samples collected from Belizean reefs were either (1) immediately preserved in ethanol (“control”), (2) held in ambient seawater for 3 h before preservation (“SW”), or (3) held in ambient seawater with menthol (a common pre-preservation relaxation technique for ascidian identification) for 3 h before preservation (“SW + M”). All <i>T. solidum</i> microbiomes were different from ambient seawater bacterioplankton and dominated by the same microbial taxa, including the genera <i>Thalassobaculum</i>, <i>Tistrella</i>, and <i>Synechocystis</i>. However, the 3-h delay in sample preservation (SW) significantly reduced microbiome richness compared to controls (<i>p</i> = 0.028), while menthol treatment (SW + M) mitigated this diversity loss (<i>p</i> = 0.208). Microbial composition at the community level did not differ significantly for either delayed preservation method compared to controls (SW <i>p</i> = 0.054, SW + M <i>p</i> = 0.052). Taxon-level shifts were rare but did occur, most notably a bloom of the facultatively anaerobic gammaproteobacterium <i>Catenococcus</i> that was 37x (SW) and 197x (SW + M) more abundant in delayed preservations. After a 3-h preservation delay (SW), only 122 microbial taxa (1.85% of total) exhibited significantly differential abundances with controls, with menthol treatment (SW + M) reducing taxon-level shifts to 65 taxa (0.98%). Our results showed that brief delays in preservation did not significantly alter community-level microbiome composition and dominant taxa, with menthol exposure counteracting minor microbiome shifts associated with preservation delays.</p>","PeriodicalId":18573,"journal":{"name":"MicrobiologyOpen","volume":"14 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mbo3.70019","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144074634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}