Folia microbiologica最新文献

{"title":"Phytochemical characterization, antioxidant, and antibacterial activities of Cymbopogon citratus extracts against multidrug-resistant uropathogens.","authors":"Kainnat Khalid, Shumaila Naz, Azka Javaid, Anas Rashid","doi":"10.1007/s12223-026-01498-y","DOIUrl":"https://doi.org/10.1007/s12223-026-01498-y","url":null,"abstract":"<p><p>Urinary tract infections (UTIs) are among the most prevalent bacterial infections worldwide, posing a significant health burden, particularly in the context of rising antimicrobial resistance. The increasing ineffectiveness of conventional antibiotics has necessitated the exploration of alternative therapeutic approaches, especially those derived from natural plant-based sources. This study aimed to evaluate the antimicrobial efficacy of Cymbopogon citratus (lemongrass) leaf extracts against multidrug-resistant uropathogens. Extracts were prepared using three solvents: methanol, ethanol, and n-hexane, and tested against three clinically relevant bacterial strains: Escherichia coli, Bacillus subtilis, and Enterobacter hormaechei subsp. xiangfangensis. Phytochemical screening revealed that extracts contained a wide variety of bioactive compounds, including alkaloids, flavonoids, saponins, tannins, terpenoids, phenols, coumarins, and volatile oils. Further analysis using Fourier-transform infrared spectroscopy identified characteristic functional groups, including O-H, C-H, C = O, C = C, and N-H, indicating the presence of alcohols, aldehydes, ketones, alkenes, and amines, which are often associated with antimicrobial activity. Antibacterial assays showed that the methanolic extract exhibited the strongest inhibitory activity. In disc diffusion tests, it produced the largest zones of inhibition: 14 mm against Escherichia coli, 14 mm against Bacillus subtilis, and 13 mm against Enterobacter hormaechei subsp. xiangfangensis. Minimum inhibitory concentration values further confirmed its superior potency, with results of 3.12 mg/mL for Escherichia coli, 6.25 mg/mL for Bacillus subtilis, and 12.5 mg/mL for Enterobacter hormaechei subsp. xiangfangensis. The extract also showed bactericidal activity, with minimum bactericidal concentrations of 12.5 mg/mL for Escherichia coli and 25 mg/mL for the other two strains. In summary, this study provides strong evidence that Cymbopogon citratus, particularly when extracted with methanol, possesses significant antibacterial and antioxidant properties against multidrug-resistant uropathogens. These findings support its potential use as a complementary or alternative therapeutic agent in managing resistant urinary tract infections, offering a promising natural strategy to address the growing challenge of antimicrobial resistance. IMPACT STATEMENT. Methanolic extracts of Cymbopogon citratus demonstrated strong antibacterial and bactericidal activity against multidrug-resistant uropathogens, including Escherichia coli and Enterobacter hormaechei subsp. xiangfangensis. Phytochemical and FTIR analyses confirmed the presence of bioactive functional groups associated with antimicrobial effects. These findings highlight lemongrass as a promising plant-based candidate for developing complementary therapies to address antimicrobial resistance in urinary tract infections and support further pharmacological standardization","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835516","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":"Laser-ablated gold nanoparticles: a novel approach to antimicrobial artificial eyes.","authors":"Alaa Mohamed, Ahmed O El-Gendy, Khaled Salah Eldin Abdelkader, Esraa Ahmed, Tarek Mohamed, Mohamed Mobarak","doi":"10.1007/s12223-026-01462-w","DOIUrl":"https://doi.org/10.1007/s12223-026-01462-w","url":null,"abstract":"<p><p>Patients with artificial eyes often suffer from severe, persistent microbial infections, particularly due to antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA). Nowadays, gold nanoparticles (AuNPs) exhibit strong antimicrobial properties, offering a promising solution to this challenge. In this study, laser ablation was employed to create AuNPs, which were added into artificial eye materials during fabrication. The antimicrobial efficacy of laser-ablated AuNPs against resistant bacteria was systematically evaluated using multiple microbiological assays. A colony forming unit and growth kinetic analysis were determined using an ANOVA test. Moreover, Logistic and Gompertz models were performed to visualize the MRSA growth kinetic rate. Our findings show that AuNPs significantly reduce bacterial growth, suggesting their potential as an effective antimicrobial component in ocular prostheses. Theoretically, the Gompertz model was the best-fit model for experimental kinetic data. We have produced a foundational framework for integrating AuNPs into artificial eyes to combat infections, paving the way for the development of novel antimicrobial ocular prostheses.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835487","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":"In Vitro probiotic assessment and optimization of enhanced spore production in submerged fermentation of Bacillus toyonensis OQ071612.","authors":"Sayed E El-Sayed","doi":"10.1007/s12223-026-01492-4","DOIUrl":"https://doi.org/10.1007/s12223-026-01492-4","url":null,"abstract":"<p><p>Certain species within the Bacillus genus, such as Bacillus toyonensis, are widely used as commercial probiotics; however, comprehensive screening and safety evaluation remain essential because some Bacillus species, including B. anthracis and B. cereus, are pathogenic and toxin-producing. In the present study, a soil-derived isolate, B. toyonensis OQ071612, exhibited strong inhibitory activity against multiple representative human enteropathogens and was therefore selected for detailed characterization. The strain demonstrated high tolerance to harsh gastrointestinal and processing-related stress conditions, including low pH, simulated gastric fluid, simulated intestinal fluid, bile salts, and elevated temperatures. In addition, B. toyonensis OQ071612 displayed several desirable probiotic attributes, such as antioxidant activity and bile salt hydrolase (BSH) activity, while showing no hemolytic activity and minimal cytotoxicity toward Caco-2 cells. Antibiotic susceptibility testing revealed sensitivity to vancomycin, levofloxacin, sulfamethoxazole, and doxycycline, with intermediate sensitivity to azithromycin and amoxicillin, indicating the absence of acquired antimicrobial resistance associated with mobile genetic elements. Response surface methodology (RSM) was employed to optimize biomass and spore production, achieving optimal conditions at pH 6.5, 40 °C, 150 rpm agitation, and 0.26 vvm aeration, resulting in 2.7-fold and 6.5-fold increases in biomass and spore yields, respectively. Furthermore, supplementation with B. toyonensis OQ071612 significantly enhanced body mass gain in rats, supporting its potential as a probiotic candidate for animal feed and suggesting possible relevance for future human applications. Collectively, these findings demonstrate that B. toyonensis OQ071612 possesses strong probiotic functionality, favorable preclinical safety characteristics, and promising industrial scalability, supporting its potential as a probiotic candidate for animal feed applications and providing a basis for future evaluation in human-related applications.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835427","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":"Co-existence of blaCTX-M and mcr-1 in avian pathogenic Escherichia coli in Southern Xinjiang: current status and antimicrobial resistance characteristics.","authors":"Bin Yang, Guofeng Xing, Wenxuan Ma, Meng Qi, Bo Jing, Jing Li, Jing Wu","doi":"10.1007/s12223-026-01496-0","DOIUrl":"https://doi.org/10.1007/s12223-026-01496-0","url":null,"abstract":"<p><p>Extended-spectrum β-lactamases (ESBLs) constitute one of the principal mechanisms underlying multidrug resistance (MDR) in avian pathogenic Escherichia coli (APEC). The coexistence of ESBL-encoding genes, particularly blaCTX-M, together with the plasmid-mediated colistin resistance gene mcr-1 in APEC raises serious concern, as it undermines the effectiveness of third-generation cephalosporins and colistin. To clarify the current epidemiological status and potential transmission risks associated with the co-occurrence of ESBL and mcr-1 genes in southern Xinjiang, 133 liver samples from chickens that had died after exhibiting clinical signs consistent with colibacillosis were collected, from which 100 of these isolates (75.2%, 100/133) were confirmed as APEC. The double-disk diffusion test revealed that 65 strains (65.0%, 65/100) were ESBL-producing. Among these ESBL-producing APEC isolates, resistance rates to ampicillin, cefazolin, ceftiofur, and cefoxitin were 100% (65/65), 100% (65/65), 92.3% (60/65), and 4.6% (3/65, intermediate/susceptible), respectively. PCR detection revealed that 95.4% (62/65) carried blaCTX-M and 93.8% (61/65) carried blaTEM and five isolates (7.7%, 5/65) were resistant to colistin and carried the mcr-1 gene. Integron analysis revealed that int1 was detected in 98.5% (64/65) of the ESBL-APEC isolates. Notably, all five mcr-1-positive strains co-harbored int1. These five isolates exhibited MDR phenotypes and were assigned to phylogenetic groups A (n = 1), B1 (n = 3), and D (n = 1). Whole-genome sequencing (WGS) revealed that the five mcr-1-positive APEC strains belonged to four sequence types (STs): ST6792 (n = 1), ST1196 (n = 2), ST155 (n = 1), and ST162 (n = 1), and harbored three blaCTX-M subtypes (blaCTX-M-55 [n = 3], blaCTX-M-64 [n = 1], and blaCTX-M-65[n = 1]). Furthermore, these strains carried IncI2 or IncFIB plasmid replicons alongside the int1 integrase gene, highlighting the co-occurrence of critical resistance determinants with mobile genetic elements known to facilitate horizontal dissemination. The coexistence of blaCTX-M and mcr-1 in high-risk clones such as ST155 and ST162, which are associated with human infections worldwide, indicates that the region faces a threat from multidrug-resistant strains and a potential risk of cross-species transmission. Given the limited geographic scope and sample size, our findings should be considered a preliminary warning. Future studies with expanded sampling and experimental validation of horizontal transfer are needed to fully assess the transmission risks.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835757","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":"Probiotic potential and antioxidant, antidiabetic, and anticancer activities of goat milk-derived lactic acid bacteria.","authors":"Sirikhwan Tinrat, Onnicha Jiraprasertwong","doi":"10.1007/s12223-026-01494-2","DOIUrl":"https://doi.org/10.1007/s12223-026-01494-2","url":null,"abstract":"<p><p>Raw goat milk was explored as a source of lactic acid bacteria (LAB) with potential probiotic properties. Following 16S rRNA gene sequencing, Lactiplantibacillus plantarum PP101-STR and Lactococcus lactis PP104-STR were selected for further probiotic assessment. L. plantarum PP101-STR exhibited broad antagonistic activity against both Gram-positive and Gram-negative pathogens, especially Salmonella enterica ATCC 13312 and maintained high viability (> 83%) under simulated gastric conditions (pH 2.0-3.0) and bile salt exposure. This strain also demonstrated high cell surface hydrophobicity, along with strong auto-aggregation and co-aggregation capacities, which were associated with significantly enhanced adhesion to Caco-2 and HT-29 cell lines and effective competitive exclusion of pathogenic bacteria (p≤0.05). In addition, L. plantarum PP101-STR displayed strong antioxidant activity, as determined by total phenolic content, FRAP, DPPH, and ABTS assays, exceeding that of L. lactis PP104-STR. Its cell-free supernatant (CFS) exhibited notable α-glucosidase and α-amylase inhibitory activities, indicating potential for glucose regulation. Antiproliferative evaluation revealed that L. plantarum PP101-STR markedly suppressed colorectal cancer cell growth in a dose-dependent manner. Importantly, low lactate dehydrogenase release (8.11-8.86%) and maintained viability in MRC-5 cells indicated minimal membrane damage and low cytotoxicity toward normal cells, supporting a non-lytic mechanism potentially involving apoptosis-related pathways. On the basis of the present finding, L. plantarum PP101-STR demonstrates strong probiotic potential and multiple biologically relevant activities in vitro, supporting its further investigation in applications related to intestinal health.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147812924","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":"Pharmacological and mechanistic assessment of Trachyspermum ammi hydrosol: antimicrobial and anti-biofilm efficacy against Staphylococcus aureus and Listeria monocytogenes.","authors":"Deepika Srivastava, Kuldeep Gupta, Parmanand Kumar, Swarnima Kaushal, Shubham Srivastava, Yatish Pant, C S Chanotiya, P K Rout, Anirban Pal","doi":"10.1007/s12223-026-01483-5","DOIUrl":"https://doi.org/10.1007/s12223-026-01483-5","url":null,"abstract":"<p><p>The escalating global threat of antimicrobial resistance (AMR), particularly among biofilm-forming bacterial pathogens, has necessitated the development of novel therapeutic strategies. Trachyspermum ammi hydrosol has exhibited a range of bioactive properties. However, its potential as a dual-action antimicrobial agent targeting both planktonic and biofilm-associated microorganisms remains underexplored. This study aimed to explore the antibacterial and antibiofilm activity of T. ammi hydrosol (TaHy) against two major Gram-positive pathogens, Staphylococcus aureus (S. aureus) and Listeria monocytogenes (L. monocytogenes), and elucidate its mechanism of action based on cell. Additionally, we aimed to evaluate in vivo acute toxicity and biosafety. Antimicrobial activities were assessed using DDA, MIC, and time-kill assays. Antibiofilm activity was evaluated using a crystal violet method, and biofilm morphology was examined by microscopy. TaHy demonstrated efficient inhibition in hydrophobicity and EPS production, along with alterations in membrane integrity, including bacteriolysis and protein and nucleic acid release. Our results showed that the MIC of TaHy was 0.625 mg/mL against both pathogens and that it significantly inhibited and eradicated biofilm formation at sub-MIC values, as confirmed by SEM and fluorescence microscopy. TaHy effectively inhibited hydrophobicity and EPS production, reducing the virulence factors of pathogens to 1/8 MIC. Consequently, in vivo acute oral toxicity tests revealed no adverse effects at doses up to 2000 mg/kg body weight of hydrosol concentrate. These findings revealed that TaHy has robust antimicrobial and antibiofilm capability against S. aureus and L. monocytogenes.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147812951","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":"Pomegranate peel extract as a promising tyrosyl-tRNA synthetase inhibitor of Staphylococcus aureus: in vitro and in silico approach.","authors":"Anita Chaudhary, Sneha Murmu, Santosh Kumar Behera, Anju Kamra, Anurag Chaurasia, Sunil Kumar","doi":"10.1007/s12223-026-01487-1","DOIUrl":"https://doi.org/10.1007/s12223-026-01487-1","url":null,"abstract":"<p><p>Staphylococcus aureus, a common foodborne pathogen, thrives in various environments, including milk, meat, and vegetables. With increasing consumer concerns about the harmful effects of chemical additives, alternative antimicrobial agents are urgently needed. This study evaluates the potential of pomegranate peel extract (PPE) as an inhibitor of the bacterial enzyme tyrosyl-tRNA synthetase (TyrRS). PPE, rich in bioactive compounds such as ellagitannins, ellagic acid, and gallic acid, was extracted using hot water, microwave, and ultrasound methods. The ultrasound assisted extract showed the highest phenol content (178.6 ± 0.6 GAE/g) and antioxidant activity (9.43 ± 1.6 µmole TE/g DW). The MIC value of this extract was found to be 2.0 mg/ml and it inhibited S. aureus growth significantly (20.6 ± 0.31 mm) in agar diffusion tests. To elucidate the molecular mechanism, in silico analyses including molecular docking, molecular dynamics simulations, and MM-PBSA calculations were performed for major PPE-derived phytochemicals, gallic acid, ellagic acid, punicalagin, and punicalin, along with the reference TyrRS inhibitor SB-219,383. Among the tested compounds, punicalagin exhibited the most favorable binding affinity and dynamic stability, with binding free energy comparable to SB-219,383. These findings highlight PPE's potential in combating S. aureus along with utilization of agricultural by-products as source of antimicrobial substance that has the potential of offering a sustainable approach to antimicrobial resistance.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147812992","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":"Investigation of chitinase B1 inhibitors targeting the cell wall biosynthetic machinery in Aspergillus fumigatus through integrated molecular dynamics and QM/MM.","authors":"Perwez Alam, Ali Akhtar, Zafrul Hasan, Mohammad Serajuddin, Omer M Almarfadi, Sarfaraz Ahmed","doi":"10.1007/s12223-026-01491-5","DOIUrl":"https://doi.org/10.1007/s12223-026-01491-5","url":null,"abstract":"","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147767010","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":"Identification of a novel mutation of sat (Gly82Arg) in Shigella flexneri serotype 7a: insights into clinical relevance.","authors":"Iqbal Nisa, Muhammad Qasim, Arnold Driessen, Jeroen Nijland, Hazir Rahman, Yasar Mehmood Yousafzai, Khalid J Alzahrani, Jochen Mattner, Niaz Muhammad, Fazli Bari, Taj Ali Khan","doi":"10.1007/s12223-026-01484-4","DOIUrl":"https://doi.org/10.1007/s12223-026-01484-4","url":null,"abstract":"","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147767046","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":"D-amino acids inhibit biofilm formation in Escherichia coli and increase antibiotic susceptibility in multidrug-resistant bacteria.","authors":"Jixue Wang, Bin Yang, Guofeng Xing, Yao Zhao, Zihao Wu, Jing Li, Meng Qi, Jing Wu","doi":"10.1007/s12223-026-01493-3","DOIUrl":"https://doi.org/10.1007/s12223-026-01493-3","url":null,"abstract":"","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766998","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}