International Microbiology最新文献

{"title":"The synergistic effect between sodium selenite and Pediococcus acidilactici on fermentation quality and aerobic stability of alfalfa silage.","authors":"Qingdong Wang, Shanshan Kuang, Chunyue Wang, Panjie Cheng, Sitong Ma, Baohong Tang","doi":"10.1007/s10123-025-00717-9","DOIUrl":"https://doi.org/10.1007/s10123-025-00717-9","url":null,"abstract":"<p><p>Selenium, an essential micronutrient that cannot be endogenously synthesized by mammals, requires exogenous dietary supplementation. Lactic acid bacteria can biotransform sodium selenite (Na₂SeO₃) into bioavailable selenium nanoparticles (SeNPs), creating multifunctional selenium-enriched forages. This study systematically assessed the synergy of SeNPs and Pediococcus acidilactici in alfalfa silage through four treatments: control (CK), P. acidilactici alone (LP), Na₂SeO₃ alone (Se), and combined treatment (LPSe). After 30 days of ensiling, fermentation quality, microbial community, and aerobic stability were determined. The results revealed that LPSe silage exhibited decreased pH, butyric acid, and binding protein contents compared with CK, while its organic selenium content (1.64 mg/kg DM) was Significantly higher than that of LP Silage. 16S rRNA sequencing showed increased abundance of Pediococcus and Lactobacillus in LPSe Silage with Simplified bacterial community structure. After 7 days of aerobic exposure, CK Silage showed rapid pH and ammonia Nitrogen increase, whereas LPSe Silage had 28.24% longer aerobic stability than CK and 11.50% longer than LP. These results demonstrate LPSe as the optimal treatment for alfalfa silage.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075288","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":"Highlight on the synergistic effect of different microemulsion formulations on the virulence determinants of multi-resistant Mycoplasma gallisepticum recovered from poultry.","authors":"Reham A Hosny, Dalia M A El Masry, Aalaa S A Saad, Fatma Amer, Waleed A Ibrahim, Nayerah M Alatfeehy","doi":"10.1007/s10123-025-00712-0","DOIUrl":"https://doi.org/10.1007/s10123-025-00712-0","url":null,"abstract":"<p><p>This study is aimed at evaluating the efficacy of essential oil-based microemulsions in combination with antimicrobials against Mycoplasma gallisepticum (MG), a major respiratory pathogen in poultry. MG was isolated from 1.1% of broiler and 0.5% of breeder flocks, with the highest incidence recorded during winter and autumn, particularly in farms located in Giza and Sharkia governorates. Among 37 confirmed isolates, eight were positive for the mgc2 gene, while six carried gapA and crmA. Cumin, camphor, and olive microemulsions exhibited favorable physicochemical characteristics. GC-MS analysis identified α-citral, ( +)-2-bornanone, and cis-vaccenic acid as the major components of cumin, camphor, and olive oils, respectively. Notably, olive/camphor and cumin microemulsions were rich in cis-vaccenic acid and linoleoyl chloride, respectively. Antibiotic susceptibility testing revealed that all isolates were resistant to lincomycin, erythromycin, spectinomycin, and tiamulin, with 50% exhibiting complete resistance to all antibiotics. Tylosin showed partial activity, inhibiting 37.5% of isolates (MIC 0.25-4 µg/mL). Camphor microemulsion demonstrated the highest antimicrobial effect (MIC 0.08-5 µg/mL). The most significant synergistic interaction was observed between cumin oil and either oxytetracycline or spiramycin, as well as between camphor microemulsion and doxycycline against MG isolates. Furthermore, combination treatments significantly downregulated the expression of mgc2, crmA, and gapA genes. These findings highlight the promising role of essential oil-based microemulsions as effective adjuncts in MG control strategies.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040030","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":"Genomic insights, determination of quorum quenching potential of a beta-lactamase enzyme from Chromohalobacter sp. strain D23 against Aeromonas hydrophila and molecular docking study.","authors":"Dhritishree Ghosh, Sk Aftabul Alam, Subhra Kanti Mukhopadhyay","doi":"10.1007/s10123-025-00705-z","DOIUrl":"https://doi.org/10.1007/s10123-025-00705-z","url":null,"abstract":"<p><p>Biofilm formation and other virulence phenotypes under quorum sensing regulation play a vital role in the pathogenicity of Aeromonas hydrophila, triggering the emergence of multi-drug resistance (MDR) which increases fish mortality, environmental issues, and economic loss in aquaculture, necessitating the discovery of novel drugs to bypass standard antibiotics. Here, quorum quenching (QQ) may be a sustainable anti-virulent approach. β-Lactamase enzyme obtained from Chromohalobacter sp. strain D23 restricted violacein pigmentation in Chromobacterium violaceum CV026 by degrading C4-homoserine lactone (C4-HSL) and C6-HSL up to 70% (P < 0.0001). HPLC study also revealed > 73% enzymatic breakdown of both C4-HSL and C6-HSL within 2 h. Crude β-lactamase also hampered biofilm formation of A. hydrophila by reducing total biomass (> 66%, P < 0.001) and cellular viability (62%, P < 0.0001) without affecting planktonic growth. QS-mediated other virulence factors of A. hydrophila, like hemolysin, serine protease, exopolysaccharides, metalloprotease, and lipase activities, were also significantly inhibited (P < 0.0001). Draft genome size of strain D23 was 3.6 mb, having 64.01% G + C content. Annotation revealed the presence of a MBL (metallo-beta-lactamase)-fold metallo-hydrolase enzyme. Multiple sequence alignment indicated the presence of the conserved ⁶⁶HXHXDH⁷¹ domain. Pairwise alignment showed 65% ≤ sequence identity with known marine lactonase enzymes. The molecular docking study revealed moderate binding affinity of β-lactamase to C4-HSL and C6-HSL (- 5.3 kcal/mol). Thus, the present study shows the potent QQ activity of β-lactamase of strain D23 against MDR A. hydrophila, targeting their pathogenesis without necessarily killing them, which can minimize the use of antibiotics in aquaculture and also suggests possible biomedical use. This study also highlights the usefulness of less explored marine bacteria as a potent source of bioactive enzymes.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145015372","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":"Application of selected starter cultures in cocoa fermentation: effects on sensory-related volatile and non-volatile organic compounds.","authors":"Julián Felipe Martínez Muñoz, Kevin Mauricio Miramag Yaqueno, Pablo Fernández Izquierdo, Fedra Ortiz Benavides","doi":"10.1007/s10123-025-00711-1","DOIUrl":"https://doi.org/10.1007/s10123-025-00711-1","url":null,"abstract":"<p><p>This study investigates the impact of a defined starter culture on the fermentation of cocoa beans and its influence on the production of volatile and non-volatile compounds related to sensory quality. A microbial consortium comprising Saccharomyces cerevisiae, Pichia kudriavzevii, Levilactobacillus brevis, and Acetobacter okinawensis was selected based on their enzymatic activity and acid regulation properties. Fermentation trials showed that the starter culture enhanced the synthesis of key volatile compounds, particularly esters and higher alcohols, such as 2-phenylethanol and 2-phenylethyl acetate, which contribute floral and fruity aromas. Compared to artisanal fermentation, treatments with starter cultures exhibited lower levels of lactic and acetic acids and an increase in succinic acid, indicating a balanced acid profile and potential metabolic synergy between inoculated and native microbiota. The study also identified specific volatile compounds as potential biochemical markers to monitor fermentation progress. These findings support the application of functional starter cultures to standardize and improve cocoa fermentation, offering opportunities to enhance quality and value in small-scale production systems.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145015388","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":"Potential of indigenous AMF from organic cassava fields in Thailand for sustainable cassava cultivation.","authors":"Kanapol Ketjarun, Juthamas Chaiwanon, Pawara Pachit, Jittra Piapukiew","doi":"10.1007/s10123-025-00708-w","DOIUrl":"https://doi.org/10.1007/s10123-025-00708-w","url":null,"abstract":"<p><p>This study investigated the potential of native arbuscular mycorrhizal fungi (AMF) isolated from organic cassava fields as a biofertilizer, assessing their effects on cassava growth both alone and in combination with plant growth-promoting bacteria (PGPB). AMF spores were isolated from the rhizospheric soil of organic cassava field soils in northeastern Thailand and grouped into two consortia based on spore size: A45 and A75. Molecular identification revealed that both consortia were dominated by the genera Claroideoglomus and Entrophospora, with Paraglomus additionally present in the A45 consortium. An outdoor pot experiment demonstrated that AMF inoculation significantly enhanced cassava growth compared to the uninoculated control, highlighting the potential of these locally adapted strains. Utilization of diverse AMF consortia showed better outcomes in cassava growth enhancement resulted from various abilities of AMF inside. However, the addition of the compatible PGPB strains (Pantoea dispersa and Serratia marcescens) did not further enhance plant growth. These findings emphasize the potential of locally adapted AMF consortia as effective biofertilizers for cassava and underscore the need for targeted evaluation of microbial interactions in sustainable agriculture.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145000578","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":"Purification and characterization of an extremely thermostable metalloprotease from Geobacillus thermoleovorans HBB208.","authors":"Sezgin Karaman, Kubilay Metin","doi":"10.1007/s10123-025-00710-2","DOIUrl":"10.1007/s10123-025-00710-2","url":null,"abstract":"<p><p>Protease enzymes are widely used in industrial applications, often requiring resistance to alkaline and high-temperature conditions while maintaining activity in organic solvents. Discovering thermotolerant proteases from thermophilic organisms is crucial for such applications. This study aimed to identify a novel thermotolerant protease among 201 thermophilic strains isolated from hot springs in Aydın province. Geobacillus thermoleovorans HBB208 was identified as the most efficient protease producer, exhibiting a 3.1 (D/d) ratio on skim milk agar. The protease purified via ammonium sulfate precipitation, hydrophobic interaction, and ion-exchange chromatography, resulting in a 70.2-fold purification. SDS-PAGE and zymogram analyses confirmed the molecular weight of approximately 33.5 kDa and proteolytic activity. The enzyme showed optimal activity at pH 8.0 and 70 °C, and retained 50% activity after 30 min at 87.3 °C in the presence of 10 mM Ca²⁺, indicating remarkable thermostability. Kinetic analysis using casein as substrate yielded a K_m of 0.11 ± 0.01 mM, k_cat 27.4 ± 0.77, and 2.4 × 10⁵ k_cat/K_m. The enzyme was stable in the presence of various organic solvents and detergents and displayed broad substrate specificity. These findings suggest that HBB208pro metalloprotease enzyme is a promising candidate for biotechnological and industrial applications requiring extreme operational conditions.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953897","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":"Differential impacts of various plant growth-promoting and osmotic tolerant bacterial strains on proline and sugar accumulation to enhance stress adaptations in tea plants.","authors":"Paritosh Baruah, Pritirekha Saikia, Jumi Gogoi, Pritom Chowdhury, Sosanka Protim Sandilya, Harisadhan Malakar, Hemanta Saikia, Sangeeta Borchetia","doi":"10.1007/s10123-025-00709-9","DOIUrl":"https://doi.org/10.1007/s10123-025-00709-9","url":null,"abstract":"<p><p>Drought stress poses a severe threat to tea plantations globally, leading to a significant reduction in yields. Use of plant growth-promoting bacteria (PGPB) has emerged as a promising strategy to alleviate the detrimental effects of water stress. This study investigates nine distinct bacterial strains, isolated from a drought-prone region in North-East India, for their plant growth-promoting (PGP) traits and their ability to mitigate osmotic stress. These strains were identified based on morphological characteristics and 16S rRNA molecular analysis. Among them, the strains-Chryseobacterium bernardetii (S₄), Cytobacillus gottheilii (S₅), Kitasatospora aureofaciens (S₇), Kocuria palustris (A), and Brachybacterium rhamnosum (B)-exhibited higher PGP activities under osmotic stress conditions (- 0.19 MPa and - 0.93 MPa induced by PEG-6000). Additionally, K. palustris (A) and B. rhamnosum (B) demonstrate effective adaptation to oxidative stress by reducing proline accumulation and were also found to be catalase (CAT) positive. The effect of these osmotolerant PGPBs was further evaluated on tea seedlings under drought stress. Pot experiments in nursery were conducted with three treatments: a positive control (plants watered frequently), a negative control (no treatment), and eight treatments (T1-T8: bacterial inoculations). When comparing the efficacy of bacterial isolates and delivery methods-bioencapsulation and soil drenching. Treatment T6 (comprising strains S₄, S₅, S₇, A, and B) inoculation via soil drenching method improved drought tolerance by effectively modulating osmolyte concentrations, as evidenced by a reduction in total soluble sugars compared to the negative control, highlighting their potential role as bioformulation enhancing osmotolerance and alleviating drought stress in tea plants.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953935","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":"Analysis of variations in cell envelope subproteome and cell length in Acinetobacter baumannii ATCC 19606^T populations by effect of temperature and desiccation.","authors":"Maite Orruño, Zaloa Bravo, Iciar Martinez, Inés Arana","doi":"10.1007/s10123-025-00706-y","DOIUrl":"https://doi.org/10.1007/s10123-025-00706-y","url":null,"abstract":"<p><p>Acinetobacter baumannii, a pathogen for humans and animals, possesses a tremendous potential to survive under hostile conditions. We studied the effect of temperature, nutrient deprivation, and desiccation on the survival of A. baumannii ATCC 19606^T by monitoring variations in cellular counts and in cell length and analyzing cell envelope subproteome during the survival process. Nutrient deprivation alone does not appear to have a negative effect on A. baumannii survival, but incubation at 37 °C in an aqueous solution provoked loss of culturability, as well as a marked increase in cell length. Although a high stability of the membrane subproteome was observed, even under environmental conditions that promote morphological changes and loss of culturability, the expression of some membrane proteins did change upon exposure to the stress. Signal peptidase I and fimbrial protein became undetectable in almost all the conditions examined, while EF-Tu (in all conditions) and MinD (in populations incubated at 37 °C) were overexpressed. The great capacity for survival displayed by A. baumannii under adverse conditions may be explained, at least in part, by its capacity to maintain the expression levels of most of its cell envelope proteins and regulate a few others.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953971","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":"Cross-resistance between halquinol and antibiotics of importance in human and animal health.","authors":"Alberto Gonçalves Evangelista, Lucas Dos Santos Janotto, Adriana Paula Possamai, Carolina Cini Perry, Francine Lemes Ribeiro, Fernando Bittencourt Luciano","doi":"10.1007/s10123-025-00707-x","DOIUrl":"https://doi.org/10.1007/s10123-025-00707-x","url":null,"abstract":"<p><p>The objective of this research was to assess whether halquinol, a zootechnical antimicrobial, can lead to cross-resistance to antibiotics of importance in human and animal health. The minimum inhibitory and bactericidal concentrations of halquinol against 37 Salmonella and Escherichia coli strains/isolates were determined, along with their resistance profiles against 14 antibiotics used in human and veterinary medicine. Sublethal exposure to halquinol was performed to evaluate the acquisition of resistance to the compound by determining new minimum inhibitory and bactericidal concentrations. Cross-resistance to other antibiotics was examined by establishing a new resistance profile after sublethal exposure and comparing it with the previous results. Resistance to halquinol was successfully induced; prior to sublethal exposure, concentrations ranging from 18.25 to 300 µg/mL were required for bacterial inhibition, whereas following sublethal exposure, these values increased to 75 to 1200 µg/mL. The induction of halquinol resistance also impacted resistance to human and veterinary antibiotics. For example, before sublethal exposure to halquinol, 71.4% of Salmonella isolates were resistant to cephalexin; after sublethal exposure, 100% of the isolates exhibited resistance. In E. coli, the percentage of azithromycin-resistant isolates increased from 66.7 to 100% following sublethal exposure. These findings indicate that halquinol, in addition to inducing resistance to itself, may also promote resistance to essential drugs in both human and veterinary medicine. Further studies, particularly molecular investigations, are necessary for a comprehensive characterization of the observed in vitro effects and to determine whether these findings are replicated in vivo.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953932","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":"Isolation and characterization of multi-drug-resistant Microbacterium esteraromaticum bacteriophage: assessment of antibacterial efficacy and genomic insights.","authors":"Shenwei Cheng, Hao Wang, Keqiang Zhang, Fuyuan Liu, Xingliang Gao, Lianzhu Du","doi":"10.1007/s10123-025-00703-1","DOIUrl":"https://doi.org/10.1007/s10123-025-00703-1","url":null,"abstract":"<p><p>Microbacterium esteraromaticum, a common bacterium utilized in the degradation of organic pollutants, is prevalently found in the wastewater environments of rural areas. However, the excessive use of antibiotics in recent years has endowed M. esteraromaticum with a broad spectrum of antibiotic resistance, transforming it into a potential high-risk contaminant capable of disseminating antibiotic resistance genes (ARGs) within the environment. Lytic bacteriophages, due to their characteristic ability to lysogenize and specifically target host bacteria, have emerged as potent biocontrol agents. In this study, a specific bacteriophage, CASP3, targeting the multi-drug resistant M. esteraromaticum (MDR-ME), was isolated from a wastewater treatment facility. The assessment of phage CASP3 revealed several noteworthy characteristics, including good tolerance and a targeted effect against multidrug-resistant MDR-ME. Studies observed that CASP3, to some extent, reduced the ARGs carried by its host. Furthermore, it demonstrated good environmental compatibility, with no significant potential risks identified. The successful isolation of CASP3 not only provides a new addition to phage resources targeting this bacterium but also offers a potential biocontrol tool for mitigating ARG dissemination and reducing public health risks in rural areas.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144799062","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}