Brazilian Journal of Microbiology最新文献

{"title":"Organic acid-associated antimicrobial and antibiofilm activity of Lactobacillus rhamnosus ATCC 7469 against Acinetobacter baumannii and Staphylococcus aureus.","authors":"Mariana Silveira Mello Silva, Priscila Cristina Bartolomeu Halicki, Carlos James Scaini, Jean Lucas de Oliveira Arias, Daniela Fernandes Ramos, Luciana Farias da Costa Avila","doi":"10.1007/s42770-026-02095-4","DOIUrl":"10.1007/s42770-026-02095-4","url":null,"abstract":"<p><p>Considering the relevance of biofilms in bacterial resistance and the need for innovative therapies against pathogenic microorganisms, alternative strategies using probiotics as antimicrobial agents have emerged. This study aimed to evaluate the antimicrobial and antibiofilm activities of the cell-free supernatant (CFS) of Lactobacillus rhamnosus ATCC 7469 against biofilm-forming strains of Acinetobacter baumannii and Staphylococcus aureus. The activity of CFS was evaluated against A. baumannii ATCC 19606, A. baumannii 301, S. aureus ATCC 12598, and S. aureus ATCC 29213. Antimicrobial activity against planktonic cells, inhibition of biofilm formation, and destruction of mature biofilms were assessed at different CFS dilutions. The corresponding concentrations of lactic and acetic acids were determined by high-performance liquid chromatography (HPLC). CFS showed high antimicrobial activity, with growth inhibition ranging from 88.26% to 100% at the two highest concentrations tested (197.8/108.7 and 107.0/54.5 mM lactic/acetic acid). At 57.8/28.3 mM, growth inhibition ranged from 60.05% to 81.65%, whereas at 27.2/13.5 mM it ranged from 21.12% to 41.03%. CFS also strongly inhibited biofilm formation, with inhibition rates ranging from 66.17% to 100%, whereas destruction of mature biofilms ranged from 24.75% to 88.11%. HPLC analysis demonstrated the presence of lactic and acetic acids in the CFS, with lactic acid being the predominant organic acid detected. Neutralization of the CFS to pH 7.0 markedly reduced its antimicrobial and antibiofilm activities, supporting an important contribution of acidity and acid-associated components to the observed effects. Overall, L. rhamnosus ATCC 7469 CFS exhibited substantial antimicrobial and antibiofilm activity against A. baumannii and S. aureus, supporting further investigation of Lactobacillus-derived CFS as a potential local antimicrobial strategy.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13612767/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036436","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":"Microbiological safety and antimicrobial resistance in cashew-based plant-based cheese analogues.","authors":"Natália Zorrer Dalmina, Amanda Ladeira Toigo, Kauane Rosane Kommers Krebs, Caroline Isabel Kothe, Roberta Fogliatto Mariot, Heryk Motta, Lívia Kmetzsch, Taís Suhre, Vinícius Klain, Ana Paula Guedes Frazzon, Fabiana Quoos Mayer, Jeverson Frazzon","doi":"10.1007/s42770-026-02092-7","DOIUrl":"10.1007/s42770-026-02092-7","url":null,"abstract":"<p><p>The demand for plant-based cheese analogues has increased in recent years, driven both by the growing adoption of vegan and vegetarian diets and by consumers seeking plant-based alternatives to animal-derived products. Their production relies on diverse raw materials and often incorporates fermentation processes involving molds, yeasts, and lactic acid bacteria (LAB). Within this context, ensuring food safety, including the antimicrobial resistance (AMR) aspects, is essential due to the complex microbial communities involved in fermentation. Therefore, this study investigated the presence of bacterial species of potential public health relevance and assessed AMR profiles and genes in plant-based cheese analogues acquired in Brazil. None of the samples tested positive for Salmonella spp., coagulase-positive Staphylococcus, or Escherichia coli, while Bacillus cereus was detected in one sample. Two atypical colonies recovered on selective media for Salmonella were identified as Cronobacter malonaticus and Delftia acidovorans. Most samples exhibited high mold and yeast counts, likely associated with fermentation and maturation processes. Among 176 LAB isolates, 11 species were identified by MALDI-TOF, and twenty representative strains were selected for antimicrobial susceptibility testing. Resistance was detected in a limited number of isolates, mainly to ciprofloxacin, tetracycline, and gentamicin, whereas C. malonaticus exhibited resistance to penicillin. Whole-genome sequencing was performed on Lactiplantibacillus plantarum, Levilactobacillus brevis, Leuconostoc mesenteroides, Enterococcus faecium, and C. malonaticus. A total of eight antimicrobial resistance genes were identified, four of which were located on plasmids in C. malonaticus and L. brevis. These findings suggest that microorganisms associated with plant-based cheese analogues may act as reservoirs of antimicrobial resistance determinants, highlighting the importance of safety assessment and microbiological surveillance of strains intended for technological or probiotic applications.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13601488/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149029726","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":"Behavior of surface contamination by Salmonella spp. on broiler carcasses during slaughter stages.","authors":"Jhennifer Arruda Schmiedt, Leonardo Ereno Tadielo, Emanoelli Aparecida Rodrigues Dos Santos, Vinicius Cunha Barcellos, Luiz Gustavo Bach, Victor Hugo Cortez Dias, Monique Ribeiro Tiba Casas, Rafaela de Melo Tavares, Ricardo Seiti Yamatogi, Luís Augusto Nero, Luciano Dos Santos Bersot","doi":"10.1007/s42770-026-02061-0","DOIUrl":"10.1007/s42770-026-02061-0","url":null,"abstract":"<p><p>Salmonella spp. is a globally relevant pathogen frequently associated with foodborne infections and poultry products. This study aimed to evaluate the occurrence and quantification of Salmonella spp. during different stages of the broiler slaughter process and to assess the association of processing stages with reductions in contamination levels. The study was conducted in a federally inspected broiler slaughterhouse in Paraná, Brazil. A total of 2,100 analyses were performed on chicken carcasses collected at seven points along the slaughter line over 20 weeks. Salmonella detection followed the ISO 6579:2017 methodology, while quantification was performed using the miniaturized most probable number (mMPN) method with molecular confirmation by the invA gene. Subsequently, 211 isolates were serotyped, and 97 Salmonella Heidelberg isolates were analyzed by pulsed-field gel electrophoresis (PFGE). The highest occurrence of Salmonella spp. was observed at the pre-scalding stage (N = 236/78.66%). Significant reductions in Salmonella counts were observed after the scalding stage, after the post-evisceration critical control point for removal of visibly contaminated carcasses (CCP 1B), and after final washing before chilling (P < 0.05). Five serovars were identified, with Salmonella Heidelberg predominating (N = 193/91.5%). PFGE analysis revealed high genetic similarity (90%) among isolates, with highly similar profiles identified at different slaughter stages and sampling weeks. These findings demonstrate that Salmonella spp. was detected throughout the slaughter process, although reductions in contamination levels were observed at specific processing stages. In addition, the detection of highly similar isolates at different sampling points and weeks contributes to the understanding of Salmonella contamination dynamics in poultry slaughterhouses.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13601411/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149029666","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":"Antimicrobial activity and chemical characterization of Algerian Thymus algeriensis essential oil incorporated in active packaging for chicken meat preservation.","authors":"Amine Amoura, Hayet Ouhadda, Takfarinas Fellag, Sarah Lammi, Slimane Kadouche, Malek Amiali, Lynda Cherifi, Marzouk Mamou, Djamel Drider, Tahar Amrouche","doi":"10.1007/s42770-026-02093-6","DOIUrl":"10.1007/s42770-026-02093-6","url":null,"abstract":"<p><p>Thymus algeriensis (T. algeriensis), a North African thyme species, exhibits notable antimicrobial potential. This study evaluated the antibacterial activity of its essential oil (EO) and assessed its application in active cellophane packaging for chicken meat preservation. The EO was impregnated onto cellophane sheets and applied in situ on chicken thighs artificially contaminated with Escherichia coli ATCC 25,922 (E. coli) and stored at 5 ± 1 °C for 96 h. The EO chemical composition was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Antimicrobial activity was assessed in vitro using disc-diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) assays against E. coli, Staphylococcus aureus ATCC 25,923 (S. aureus), Candida albicans ATCC 71,453 (C. albicans), and Aspergillus niger ATCC 16,404 (A. niger). Results showed a marked reduction in microbial load in EO-treated samples compared with controls, demonstrating the effectiveness of EO-based active packaging in inhibiting bacterial growth under refrigerated storage. These findings support the potential of T. algeriensis EO as a bioactive natural preservative for active food packaging systems to enhance food safety and extend shelf life.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13593987/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149015555","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":"Industrial-scale optimization of fed-batch fermentation enhances biomass productivity of Pasteurella multocida B:2 for hemorrhagic septicemia vaccine.","authors":"Asfa Rasool, Sumiyya Sattar, Muhammad Zahid Farooq, Ali Abbas, Sajjad Hussain, Hina Afroz, Nadeem Akram, Abdur Rahman Ansari","doi":"10.1007/s42770-026-02088-3","DOIUrl":"10.1007/s42770-026-02088-3","url":null,"abstract":"<p><p>Hemorrhagic septicemia (HS), caused by Pasteurella multocida serotype B:2, remains a major transboundary disease of cattle and buffalo, particularly in tropical regions. Efficient vaccine production requires high-density biomass generation under controlled and scalable fermentation conditions. This study designed as a sequential process-development and optimization study aimed to optimize industrial-scale cultivation of P. multocida B:2 using a 150-L bioreactor system with S1-S5 samples (n = 5) representing independent fermentation runs from analytical measurements through media selection, fed-batch supplementation, pH control, and thermal preconditioning strategies. Comparative batch cultivation demonstrated superior biomass production in tryptose phosphate broth (TPB) compared to casein sucrose yeast (CSY) medium (OD600 1.57 vs 0.76; p < 0.001). Implementation of fed-batch supplementation significantly enhanced cell density, with a glucose-yeast extract-heart infusion formulation yielding the highest biomass (OD600 3.96; 1.98 × 10⁹ cells/mL) within 8 h of fermentation. Optimal growth was achieved at a controlled pH range of 7.30-7.35, which reduced fermentation time by approximately 33% compared to pH 7.40-7.45. Additionally, pre-heating the culture medium to 40°C prior to inoculation significantly increased biomass yield (p < 0.001). Overall, process intensification through optimized fed-batch strategy and pH control resulted in a > 2.5-fold increase in biomass productivity compared to conventional batch cultivation. These findings provide a scalable and cost-effective fermentation framework for improved commercial production of HS vaccine antigen.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13589018/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149001208","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":"Screening and ARTP mutagenesis-based breeding of high-cellulase-producing strains.","authors":"Laiyou Wang, Jintao Fang, Wei Chen, Yongpeng Jia, Liqing Guo, Shuang Cheng, Shuxian Guo, Bingbing Liu","doi":"10.1007/s42770-026-02086-5","DOIUrl":"10.1007/s42770-026-02086-5","url":null,"abstract":"<p><p>While lignocellulose is an abundant renewable resource, the discovery of microorganisms capable of degrading lignocellulose is important for its full utilization. In this study, 26 soil samples were collected from Jigongshan National Nature Reserve, Xinyang, China. The Congo red staining method was used to isolate strains capable of degrading lignocellulose from the soil samples. A strain W-6-1, isolated from the soil samples was able to effectively degrade lignocellulose, with the filter paper activity (FPA) in the fermentation broth reaching 3.34 ± 0.32 U/mL. Integrating morphological traits, 16S rRNA phylogeny and physiological-biochemical assays, the isolate was identified as Bacillus sp. W-6-1. Three rounds of atmospheric and room-temperature plasma (ARTP) mutagenesis were employed to further enhance the lignocellulose-degrading ability of this strain. The best mutant (strain M3-35), which was selected from the surviving colonies, achieved an FPA of 6.11 ± 0.27 U/mL, representing an 83% increase over the wild-type strain W-6-1. Moreover, after multiple successive transfers, the FPA of strain M3-35 remained stable. The mutant M3-35 generated in this work provides a promising laboratory-derived candidate for exploring lignocellulose bioconversion.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575069/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148966381","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":"Genomic detection of highly pathogenic avian influenza H5N1 in Antarctic seabirds reveals connectivity with South American viral lineages.","authors":"Francine C B Timm, Raíssa Gasparetto, Miguel L Côrrea, Alanis S Melgarejo, Bruna S Paredes-Galarza, Nicole V Stone, Eduardo J Pizarro, Gaspar Mejías, Carolina P Lucca, Isabella Grazini-Capelin, Fernanda M Pereira, Luis G Santos, Thales Bermann, Bruno A Prandi, Lina M Violet-Lozano, Martha T Oliveira, Lucas Krüger, Ana C Franco","doi":"10.1007/s42770-026-02076-7","DOIUrl":"10.1007/s42770-026-02076-7","url":null,"abstract":"<p><p>Emerging avian viruses increasingly threaten Antarctic wildlife, raising concerns about ecosystem health and biodiversity. In this study, we conducted a comprehensive investigation of avian influenza virus (influenza A virus, IAV) in both resident and migratory birds inhabiting the South Shetland Islands, Antarctica. During the 2024-2025 austral summer, 278 samples were collected and screened using real-time RT-PCR targeting the IAV M gene. IAV RNA was detected in 30 samples, and eight of these were found to be positive for H5. Complete genome sequencing was performed on samples from a gentoo penguin (Pygoscelis papua) and a southern giant petrel (Macronectes giganteus), revealing the presence of highly pathogenic avian influenza virus H5N1, clade 2.3.4.4b. Phylogenetic analysis demonstrated that these viral genomes closely cluster with contemporary South American strains, indicating a direct connectivity between Antarctic seabirds and the broader H5N1 transmission network. Our findings highlight the heightened vulnerability of Antarctic ecosystems to emerging infectious diseases and emphasize the critical need for sustained genomic surveillance. These efforts are essential to monitor wildlife health, inform conservation strategies, and implement effective biosecurity measures to safeguard Antarctic biodiversity.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575050/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148966387","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":"Evaluation of in vitro activity of delafloxacin against Staphylococcus aureus MSSA and MRSA isolated from a Brazilian tertiary hospital.","authors":"Patricia Orlandi Barth, Laura Ribas Ucha, Larissa Lutz, Afonso Luís Barth","doi":"10.1007/s42770-026-02084-7","DOIUrl":"10.1007/s42770-026-02084-7","url":null,"abstract":"<p><strong>Introduction: </strong>Proper treatment for infections caused by Staphylococcus aureus, particularly methicillin-resistant strains (MRSA), remains a constant challenge in hospital settings. In this context, the search for new antimicrobials, such as delafloxacin, has become necessary. Delafloxacin is a novel quinolone with a broad spectrum of activity against both gram-positive and gram-negative bacteria, offering a new therapeutic option for the treatment of infections caused by multidrug-resistant bacteria.</p><p><strong>Materials and methods: </strong>117 S. aureus isolates were included in this study: 48 S. aureus methicillin-susceptible (MSSA) and 69 S. aureus methicillin-resistant (MRSA). Isolates were recovered from skin and soft tissue sites, respiratory tract, and blood cultures. Delafloxacin susceptibility was assessed using the gradient diffusion strip (Liofilchem^®), and the results were interpreted according to the BrCAST guidelines. To assess the clonal profile of S. aureus, Fourier-transform infrared (FTIR) spectroscopy was employed using the IR Biotyper system.</p><p><strong>Results: </strong>Susceptibility to delafloxacin varied from 97.8% to 54.7% for isolates from skin/soft tissue and from respiratory tract, respectively. Blood culture isolates exhibited a Minimum Inhibitory Concentration (MIC) ≤ 0.5 mg/L. FTIR analysis using the IR Biotyper indicated a diverse distribution among the isolates.</p><p><strong>Discussion: </strong>Due to the high sensitivity rates found in this study, delafloxacin may be considered as a good therapeutic option for the treatment of S. aureus infections, including MRSA, particularly in skin and soft tissue infections. The IR Biotyper analysis revealed considerable clonal variation among the isolates, enhancing the robustness of the study.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575000/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148966321","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":"Postbiotic potential of heat-inactivated Limosilactobacillus reuteri and its cell-free supernatant in protecting intestinal health of zebrafish.","authors":"Weijuan Zhong, Huanrong He, Kaihong Hu, Kunming Huang, Biao Jiang, Chun Liu, Yanhua Huang, Youlu Su, Wei Li","doi":"10.1007/s42770-026-02085-6","DOIUrl":"10.1007/s42770-026-02085-6","url":null,"abstract":"<p><p>Postbiotics are non-viable substances derived from probiotics, offering advantages including high stability, strong safety profiles, and broad-spectrum effects. The present study aims to investigate the impact of Limosilactobacillus reuteri postbiotics on the intestinal health of zebrafish. Zebrafish were fed basal diet supplemented with either 10⁷ CFU/g heat-inactivated L. reuteri (hLR) or corresponding cell-free L. reuteri supernatant (LRs) for 14 days. Compared to the control group (CT), villus height in the zebrafish foregut and midgut were increased in LRs group. In addition, intestinal superoxide dismutase activity was significantly enhanced in hLR group and LRs group. Gut microbiota analysis revealed that both the hLR and LRs groups exhibited increased OTUs richness, altered microbial community structure at the phylum and genus levels, and reduced abundance of potential pathogenic bacteria in the gut community structure. Moreover, transcriptome analysis indicated that the functional enrichment of differentially expressed genes in the hLR group was primarily focused on immune regulation, while that in the LRs group was mainly concentrated on cell cycle regulation. The present study found that different postbiotic components of L. reuteri exerted distinct effects on zebrafish intestinal health, providing crucial evidence for the application of L. reuteri postbiotics as an effective feed additive in aquaculture.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13574741/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148966411","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":"Structural elucidation, antimicrobial activity, and cytotoxic potential of 6-methyl-1,3,8-trihydroxyanthraquinone and 1,8-dihydroxy-3-methylanthracenedione-9,10-dione compounds from mangrove derived rare actinobacterium Pseudonocardia parietis VLCH-6.","authors":"Chiranjeevi Chetapalli, Nagaraju Kumbha, Mary Swapna Mogili, Vijayalakshmi Muvva, Vengateshwaran Thasu Dinakaran","doi":"10.1007/s42770-026-02072-x","DOIUrl":"10.1007/s42770-026-02072-x","url":null,"abstract":"<p><p>Actinobacteria of mangrove habitats are the potential source of natural products. The work has been undertaken to optimize cultural conditions and elucidate the bioactive compounds produced by a mangrove derived potent rare actinobacterium. Pseudonocardia parietis VLCH-6 was proved as the potent actinobacterium strain, which was derived from the Machilipatnam mangrove habitats of Andhra Pradesh. This identification was based on polyphasic taxonomy, which included morphological, cultural, physiological, biochemical, and molecular approaches. During optimization process, ISP-2 (YMD) broth was recorded as suitable culture medium for enhanced metabolites yield. For maximum yield of the bioactive metabolites, glucose (2%) as carbon source and tryptone (1%) as nitrogen source were noticed. Further, after incubating the strain at 35⁰C for seven days, the optimum yield was observed when it was grown in a modified YMD culture medium that had been amended with NaCl (3%) and K₂HPO₄ (0.05%) to achieve a pH of 7. High antagonistic activity was demonstrated by the metabolites extracted from the optimized culture broth against a diverse array of pathogens. The isolation of two compounds with potential antimicrobial activity was achieved through column chromatography purification. The structures of bioactive compounds were elucidated through spectroscopic analysis including EIMS, FTIR, ¹H NMR and ¹³C NMR spectra. The two bioactive compounds were characterized as 6-methyl-1,3,8-trihydroxyanthraquinone and 1,8-dihydroxy-3-methylanthracenedione-9,10-dione. These compounds exhibited potential antimicrobial (MIC), anticancer activities against MCF-7 human breast cancer cell line and HEK293 human embryonic kidney cell line. This is the first publication on the characterization of bioactive chemicals produced by Pseudonocardia parietis VLCH-6.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13569816/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148943794","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}