Brazilian Journal of Microbiology最新文献

{"title":"Molecular detection of Streptococcus Sp. isolated from the mouth and nose of humans and pets.","authors":"Hassan F Mohammed, Ibrahim M Kamal, Ban S Al-Nasiry, Nadir F Habubi","doi":"10.1007/s42770-026-02101-9","DOIUrl":"https://doi.org/10.1007/s42770-026-02101-9","url":null,"abstract":"<p><p>Several streptococcal species traverse the human-animal-environment interface, positioning them as particularly compelling subjects for One Health research. In contrast to strictly host-adapted pathogens, these species are observed to circulate among livestock, companion animals, aquaculture, and the broader environment, exhibiting demonstrable transmission to human populations. In this study, 200 swabs were collected from humans and animals (100 nasal and oral swabs were tested bacteriologically from individuals with respiratory infections and gastrointestinal illnesses of all genders and ages. 100 swabs were collected from pets (dogs and cats) of both genders and various ages. Various respiratory symptoms were tested to isolate and characterize the bacterial causes of respiratory infections and to identify bacteria that can infect both humans and their pets. Finally, the results were confirmed by primary culture media, the Vitk 2 system, and 16 S rRNA. The results of bacterial isolation from the human nose showed the presence of six streptococcal isolates, classified into three types: S. thoraltensis (3, 50%), followed by S. anginosus (2, 33.33%), and finally S. alactolyticus (1, 16.66%). Moreover, the results from the human mouth showed the existence of 15 streptococcal isolates, divided into four types: S. salivarius (5, 33.33%), followed by S. thoraltensis (4, 26.66%), then S. alactolyticus and S. parasanguinis (3, 20%). At the same time, the results from the dog nose showed the presence of four streptococcal isolates, classified into three types: S. anginosus (2, 50%), followed by S. thoraltensis and S. alactolyticus (1, 25%). The results from the dog oral samples showed the presence of 16 streptococcal isolates, divided into four types: S. salivarius (6, 37.5%), S. alactolyticus (4, 25%), and S. thoraltensis and S. parasanguinis (3, 18.75%). Moreover, the cat nose results showed the presence of three streptococcal isolates, all classified as S. anginosus (100%). The results from the cat oral swab showed the presence of 8 streptococcal isolates, divided into four types: S. thoraltensis (3; 37.5%), S. parasanguinis and S. alactolyticus (2; 25%), and S. salivarius (1; 12.5%). Additionally, the identification of 6 Streptococcus sp. strains was confirmed using the 16 S rRNA gene.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149223213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating microgen GN A + B-ID versus API 20E for the identification of Salmonella spp. in food.","authors":"Xiaojuan Yang, Shuzhen Cai, Jiahui Huang, Tingting Liu, Chengsi Li","doi":"10.1007/s42770-026-02120-6","DOIUrl":"https://doi.org/10.1007/s42770-026-02120-6","url":null,"abstract":"<p><p>This study assessed the performance of the Microgen GN A + B-ID system for identifying Salmonella spp. by comparing it with the API 20E method using 284 strains isolated from food. All 284 strains were identified as Salmonella spp. by both systems, showing perfect genus-level concordance. However, in 21 strains (7.4%), the Microgen GN A + B-ID system showed biochemical reaction profiles that differed from those obtained with API 20E. Further investigation using conventional biochemical methods indicated that these discrepancies were associated with the GN B strip, a complementary component of the system designed to assess additional biochemical reactions, which showed false-negative results for inositol, rhamnose, and sorbitol, and a false-positive result for arginine. In this study, the Microgen GN A + B-ID system showed genus-level identification performance comparable to that of API 20E. The GN A strip alone proved sufficient for genus-level identification, whereas combining it with the GN B strip provides more comprehensive biochemical data but requires careful interpretation due to the risk of discrepant reactions in specific tests.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149223179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Lactic acid bacteria, potentially probiotic, in whole-grain pet biscuits: survival and technological potential of millet-based formulations (Pennisetum glaucum).","authors":"Wendy Carla Dantas Rocha, Isabel Luísa Ribeiro de Abreu Teixeira, Maria Eduarda Costa Campos, Taynan Jonatha Neves Costa, Isabella Maciel Costa, Debora Cristina Sampaio de Assis, Felipe Machado Trombete, Washington Azevedo da Silva, Erika Ramos de Alvarenga, Fabiola de Oliveira Paes Leme, Verônica Ortiz Alvarenga, Bruna Maria Salotti de Souza","doi":"10.1007/s42770-026-02113-5","DOIUrl":"10.1007/s42770-026-02113-5","url":null,"abstract":"","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13675460/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal and production-related determinants of microbial counts in pingo, the natural starter culture of minas artisanal cheese.","authors":"Gustavo Augusto Lacorte, Daniel Arantes Pereira, Joao Paulo Andrade de Araújo, Danielle Stornino de Freitas, Gabriel Henrique Oliveira Silva, Jaqueline Flaviana Oliveira de Sá, Jonas E Silva Guimarães, Milene Therezinha das Dores, Fernanda Faria Quadros","doi":"10.1007/s42770-026-02118-0","DOIUrl":"10.1007/s42770-026-02118-0","url":null,"abstract":"<p><p>Minas Artisanal Cheese (MAC) is among the most widely consumed and recognized artisanal cheeses in Brazil, produced from raw milk, rennet, salt, and a natural starter culture known locally as pingo. Pingo is an endogenous starter culture generated by backslopping, which carries into MAC cheese both technologically beneficial microorganisms and spoilage contaminants. Studies addressing the microbial diversity of MAC have accumulated in recent years, yet few have examined the composition of the microorganisms present in pingo or the factors that may influence microbial loads in this endogenous culture. Here we analysed 200 pingo samples from 50 cheesemaking units distributed across all MAC producing microregions, collected over four six-monthly campaigns. Lactic acid bacteria (LAB), total coliform, Staphylococcus aureus, and yeast/mould counts were estimated, and pH and NaCl concentration were determined. Linear mixed-effects models showed that LAB counts remained similar across sampling campaigns, although counts on MRS agar were associated with production scale and pingo volume. Total coliform counts in pingo were approximately tenfold higher during the wet season, whereas yeasts/moulds counts were associated with both season and sampling campaign. The effect of season on S. aureus depended on the year: counts did not differ between seasons in 2024 but were higher in the dry season in 2025. Smaller cheesemaking units additionally showed lower S. aureus counts in pingo. Milking infrastructure, pH, and NaCl concentration showed no association with the counts of any microbial group investigated. Our results revealed that the wet season is a period of elevated risk for the occurrence of potentially spoilage-causing microorganisms, irrespective of the scale of the cheesemaking unit and of the robustness of the installed milk production infrastructure.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13675450/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of herpesvirus, polyomavirus, and respiratory viruses in saliva from a Quilombola community in the Brazilian Amazon.","authors":"Wanderley Pansani, Samuel Nascimento Santos, Érica Correia Ramos, Barbara Júlia de Mello, Jane Glébia de Abreu, Matheus Esteves Fernandes, Pablo Fortunato da Silva, Guilherme José Costa Silva, Jane de Eston Armond, Stella de Souza Vieira, Jonatas Bussador do Amaral, André Luis Lacerda Bachi, Luiz Henrique da Silva Nali","doi":"10.1007/s42770-026-02110-8","DOIUrl":"10.1007/s42770-026-02110-8","url":null,"abstract":"<p><strong>Introduction: </strong>Quilombola communities, composed of descendants of enslaved individuals from Brazil's colonial period, often face limited access to healthcare, which may increase their susceptibility to viral infections. Oral transmission routes, particularly through saliva, are relevant for viruses such as those in the Polyomaviridae family. Therefore, here we aimed to investigate the prevalence of HSV-1, JC (JCV), and BK polyomaviruses, and respiratory viruses (Influenza A/B, RSV, SARS-CoV-2), as well as the salivary inflammatory profile in individuals from a Quilombola community.</p><p><strong>Methods: </strong>A cross-sectional study was conducted in the Quilombola community of Mangabeira, Pará, Brazil. Unstimulated saliva samples were collected from 100 individuals. Oral health was assessed, and nucleic acids were analyzed using real-time PCR (JCPyV, BKPyV, HSV-1) and multiplex TaqMan PCR (RSV, Influenza A/B, SARS-CoV-2). Cytokines (IL-6, IFN-γ, TNF-α, IL-10) were quantified.</p><p><strong>Results: </strong>BKPyV was detected in 19%, while HSV-1 and SARS-CoV-2 were found in 3% each. No cases of JCPyV, RSV, or Influenza were detected. BKPyV infection was associated with elevated IFN-γ (p < 0.01). SARS-CoV-2 and HSV-1 infections were linked to pro-inflammatory cytokine profiles. No association was found between viral detection and tooth loss or the use of prosthesis.</p><p><strong>Conclusion: </strong>A high prevalence of BKPyV and a salivary pro-inflammatory response were observed, highlighting potential oral health vulnerabilities in this underserved population.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13658731/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 insights on carbon source influence on azomycin production by Streptomyces eurocidicus.","authors":"Julia de Macedo Robert, Wagner Lopes, Alexandre Andrade de Souza Costa, Otavio Padula de Miranda, Tatiane Aparecida Nascimento, Maria da Conceição Avelino Dias, Filipe Soares Quirino da Silva, Fabius Vieira Leineweber, Graziela Jardim Pacheco","doi":"10.1007/s42770-026-02102-8","DOIUrl":"10.1007/s42770-026-02102-8","url":null,"abstract":"<p><p>Azomycin (2-nitroimidazole), a compound synthesized by Streptomyces eurocidicus, is medically significant as a build block for the drug applied in treatment for drug-resistant tuberculosis and Chagas disease, as well as tumor hypoxia imaging. Despite its clinical value, the optimized bioprocess parameters for its production remain largely unexplored. This study evaluated the influence of various carbon and nitrogen sources (specifically glucose, starch, soybean oil, and casamino acids) on azomycin yields during submerged cultivation. Batch fermentations revealed that azomycin biosynthesis is phase-shifted, initiating only after the primary carbon source is near depletion. Notably, although soybean oil served as an excellent carbon source for biomass accumulation, it yielded no detectable azomycin production. By contrast, supplementing the media with free amino acids (casamino acids) substantially enhanced product synthesis. Using an optimized semi-defined medium of glucose and casamino acids, a titer of 46.34 mg/L was achieved in 250 mL DASbox system. Scaling this configuration to an instrumented 3 L bioreactor resulted in a final concentration of 69.18 mg/L over 7 days, marking an 89% increase in the product-to-biomass yield (Yp/x) compared to the smaller scale tested. Liquid chromatography-mass spectrometry (LC-MS) verified the identity of the extracted 2-nitroimidazole. These findings demonstrate that the precision balancing of glucose and organic nitrogen is essential to unlock and maximize the biosynthetic potential of wild-type S. eurocidicus.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13658643/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of bla_NDM-5 and bla_NDM-29 variants and genetic diversity among Enterobacterales in hospitalized patients in northeastern Brazil : Variability of bla _NDM in Enterobacterales.","authors":"Lamartine Rodrigues Martins, Érica Maria de Oliveira, Maria Izabely Silva Pimentel, Elizabeth Maria Bispo Beltrão, Ana Catarina de Souza Lopes","doi":"10.1007/s42770-026-02109-1","DOIUrl":"10.1007/s42770-026-02109-1","url":null,"abstract":"<p><p>This study investigated the genetic diversity and occurrence of bla_NDM variants associated with carbapenem resistance in Enterobacterales obtained from colonization (rectal swabs) and infection sites in patients hospitalized in a public hospital in northeastern Brazil. A total of 58 multidrug-resistant clinical isolates were analyzed using ERIC-PCR to assess clonal relatedness, and PCR followed by amplicon sequencing to detect resistance genes (bla_NDM, bla_KPC, bla_GES, bla_VIM, and bla_IMP). Klebsiella pneumoniae was the most frequently identified species (n = 28, 48.27%), followed by Serratia marcescens and Proteus mirabilis, among others. All seven P. mirabilis isolates were classified as XDR, as were six K. pneumoniae and three S. marcescens isolates. Amikacin (n = 46, 79.31% susceptible) and colistin (n = 37, 97.37% susceptible) exhibited the highest susceptibility rates among all antimicrobials tested against the majority of isolates. ERIC-PCR revealed multiclonal dissemination and high genetic variability among the isolates. The bla_KPC gene was the most prevalent (n = 32, 55.17%), followed by bla_NDM (n = 26, 44.83%). Among the bla_NDM allelic variants, bla_NDM-1 (n = 12, 46.15%) was the most common, followed by bla_NDM-5 (n = 7, 26.92%) and bla_NDM-29 (n = 1, 3.85%). This study reports the first detection in Brazil of bla_NDM-5 in Klebsiella aerogenes, Citrobacter freundii, and Escherichia coli, in addition to reporting the first identification of bla_NDM-29 in K. pneumoniae. Additionally, this study gives the first report in the Americas of bla_NDM in Klebsiella ozaenae. These findings highlight the substantial potential for mutation and interspecies dissemination of bla_NDM variants within the Enterobacterales order.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13658671/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual biocontrol strategy: Fluorescent pseudomonads and methylotrophic bacteria in combating Corynespora leaf spot in blackgram.","authors":"Dasari Manikantha, V Manoj Kumar, V Vasanthi, K K Chetan","doi":"10.1007/s42770-026-02115-3","DOIUrl":"10.1007/s42770-026-02115-3","url":null,"abstract":"<p><p>Blackgram leaf spot, caused by Corynespora cassiicola, is a serious disease that significantly reduces global blackgram production. The non-commercial nature of the crop and growing nutritional significance in recent years made it necessary to implement an economical and environmentally responsible disease management strategy. In this line, twenty isolates each of fluorescent pseudomonads (FP) and facultative methylotrophs (FM) were isolated from the black gram phyllosphere. In vitro dual-culture assays demonstrated the potential of FPs (CBP-05, PPP-01) and FMs (PPM-01, ABM-04) to inhibit the mycelial growth of C. cassiicola. Further, 16S rRNA sequencing assigned the potential isolates PPP-01 and CBP-05 to Pseudomonas fluorescens, while the FM isolates PPM-01 and ABM-04 were assigned to Methylobacterium indicum and Hyphomicrobium facile, respectively. The co-culture assay revealed mutual compatibility between FP and FM. An exploration of their possible biocontrol mechanisms revealed key functions such as the production of indole-3-acetic acid, secretion of extracellular enzymes (catalases, amylases, ureases and proteases), hydrogen cyanide synthesis, siderophore production and solubilization of phosphate and potassium. Field tests with foliar spray of the consortium comprising CBP-05, PPP-01, PPM-01 and ABM-04 resulted in the lowest percentage disease index against Corynespora leaf spot (36.37%) along with a marked increase in crop yield comparable to chemical control during two consecutive years (November-April) 2020-21 and 2021-22. This study highlights the potential of a dual-functional FP-FM consortium to enhance plant growth, suppress pathogens, and provide an effective biocontrol solution for Corynespora leaf spot in blackgram.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13658735/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149165600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Escherichia coli bacteriophage vB_EcoS_MS2 effectively prevents biofilm formation but shows limited activity against mature biofilms.","authors":"Nur Isz Aishah Ismail, Liat Hung Cheah, Mohd Termizi Yusof, Hasliza Abu Hassim, Zulkifli Idrus, Roseliza Roslee, Mohd Asrore Mohd Shaufi","doi":"10.1007/s42770-026-02116-2","DOIUrl":"10.1007/s42770-026-02116-2","url":null,"abstract":"<p><p>Pathogenic Escherichia coli biofilms pose a significant challenge in veterinary and clinical settings due to their high antibiotic resistance. This study characterizes the E. coli bacteriophage vB_EcoS_MS2 as a potential targeted biocontrol agent against these pathogens. Host range determination revealed high specificity, with vB_EcoS_MS2 lysing only select E. coli strains and demonstrating superior replication efficiency (Efficiency of Plating: 112.57%) on strain C4 compared to its propagation host, MS2. While nutrient limitation strongly induced biofilm formation in in vitro assays, phage vB_EcoS_MS2 demonstrated potent prophylactic activity, inhibiting initial biofilm development by over 70% across all tested concentrations (10⁴-10⁹ PFU/mL). Conversely, the phage showed limited and transient efficacy in eradicating mature, 48-hour-old biofilms under the tested conditions. Whole-genome sequencing confirmed a 40,209 bp circular genome belonging to the class Caudoviricetes, encoding a robust holin-endopeptidase lytic cassette without carrying known antimicrobial resistance determinants. These findings indicate that while vB_EcoS_MS2 is highly effective for prophylactic biofilm prevention, complementary strategies may be required to clear established biofilms.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13652997/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149147305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance evaluation of Nile tilapia (Oreochromis niloticus) fed diets supplemented with Lactobacillus plantarum, Bacillus subtilis and Candida infanticola.","authors":"Wanderson Duarte Penido, Diego Fernandes Livio, Vinícius Souza Tarabal, Luísa Ferreira da Cruz, Alessandra de Almeida Rosa Penido, Gabriela Celeste Moreira da Silveira, Layla Conceição Aparecida Dos Santos, Dayvid Vincent de Araújo Dutra, Michelle Lucia Diniz Melo, Danilo José Santos Gomes, Newton Moreno Sanches, Ralph Gruppi Thome, Thaís Paula de Araújo, Eloisa Simões Saliba, Paulo Afonso Granjeiro, Juliana Teixeira Magalhães, Carlos Henrique Figueiredo Vasconcellos, Daniel Bonoto Gonçalves","doi":"10.1007/s42770-026-02112-6","DOIUrl":"10.1007/s42770-026-02112-6","url":null,"abstract":"<p><p>Aquaculture is the fastest-growing agricultural activity globally, providing healthy food with comparatively low environmental impact. However, high stocking densities can generate excessive organic matter, causing stress and increasing pathogen susceptibility in fish. This study evaluated the effects of dietary supplementation with Candida infanticola UFSJ7A, Bacillus subtilis ATCC 19,659, and Lactobacillus plantarum UFSJP2 on Nile tilapia (Oreochromis niloticus) performance, intestinal morphology, in vitro antagonistic activity against fish pathogens, and pond water quality. Supplementation with B. subtilis significantly improved feed conversion ratio, showing results similar to those of L. plantarum and microbial consortium treatments. Dietary supplementation significantly affected feed intake and feed conversion ratio. Fish fed L. plantarum showed the lowest feed intake, whereas the microbial consortium resulted in the highest feed intake. Supplementation with B. subtilis improved feed conversion ratio, with values comparable to those observed for L. plantarum and the microbial consortium. No significant differences were observed in final weight, weight gain, or survival among treatments. No significant effects were observed on fish viability, with survival rates above 90% across treatments. Exploratory intestinal morphometric observations indicated greater microvillus height in fish supplemented with L. plantarum and B. subtilis, suggesting increased nutrient absorption capacity. In vitro antagonism assays demonstrated that only B. subtilis inhibited the growth of (A) hydrophila, whereas L. plantarum and C. infanticola exhibited no antagonistic activity against the tested pathogens. None of the dietary treatments negatively affected water quality, which remained within suitable ranges throughout the experimental period. Overall, dietary supplementation with (B) subtilis improved feed utilization, whereas B. subtilis and L. plantarum were associated with exploratory changes in intestinal morphology. Moreover, the in vitro antagonistic activity exhibited by B. subtilis highlights its potential for future investigations on disease prevention strategies in Nile tilapia.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13653004/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149147872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}