International Journal of Microbiology最新文献

{"title":"Prevalence of Extended-Spectrum Beta-Lactamase (ESBL)-Producing <i>Escherichia coli</i> in Humans, Food, and Environment in Kathmandu, Nepal: Findings From ESBL <i>E. coli</i> Tricycle Project.","authors":"Jyoti Acharya, Runa Jha, Tulsi Ram Gompo, Sharmila Chapagain, Lilee Shrestha, Nisha Rijal, Anjana Shrestha, Pragya Koirala, Suraj Subedi, Binita Tamang, Hari Prasad Kattel, Bishal Khaniya, Basudha Shrestha, Aruna Karki, Ram Prasad Adhikari, Sanita Kayastha, Prasil Pradhan, Sarada Duwal Shrestha, Bijendra Raj Raghubanshi, Heera Tuladhar, Palpasa Kansakar, Saugat Shrestha, Priyanka Shrestha, Binay Shrestha, Ricardo J Soares Magalhaes, Manish Kakkar, Arunkumar Govindakarnavar, Allison Gocotano, Reuben Samuel","doi":"10.1155/2024/1094816","DOIUrl":"https://doi.org/10.1155/2024/1094816","url":null,"abstract":"<p><p>The need to address antimicrobial resistance (AMR) through a One Health (OH) approach is now well recognized. There is, however, limited guidance on how AMR surveillance should be implemented across sectors to generate meaningful AMR and AMU data for decision-making. Using a sympatric approach to cross-sector sample collection, Nepal adopted the WHO extended-spectrum beta-lactamase (ESBL)-producing <i>Escherichia coli</i> (<i>E. coli</i>) Tricycle Project as a step toward OH surveillance for assessing the prevalence of ESBL-producing <i>E. coli</i> across human, veterinary, and environment sectors. This involved a three-stage approach: identification of human hotspots (Stage 1) and sample collection sites for poultry (Stage 2) and wastewater (Stage 3). A total of 53 blood cultures from patients with bloodstream infections (BSIs), 100 stool samples from healthy pregnant women, 220 poultry ceca from slaughterhouses and live markets, and 48 wastewater samples were processed for bacterial culture and analyzed for the presence of ESBL-producing <i>E. coli</i>. The prevalence of ESBL-producing <i>E. coli</i> among isolated <i>E. coli</i> was the highest in wastewater samples (91%) followed by human BSIs (49%), poultry (38.6%), and fecal carriage isolates from healthy pregnant females (15%). A statistically significant association was seen in the prevalence of multidrug resistance among ESBL producers (52%) and nonproducers (26%). ESBL-producing <i>E. coli</i> was detected in all wastewater samples tested except for the upstream river. The findings of the study showed a high prevalence of ESBL-producing <i>E. coli</i> in samples from all three sectors and provided baseline data based upon which strategies for the safe disposal of communal and hospital waste, integrated AMR surveillance, and control strategies could be planned and implemented.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"1094816"},"PeriodicalIF":2.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11498988/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142499982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Myrtenol's Effectiveness against Hospital-Acquired Methicillin-Resistant <i>Staphylococcus aureus</i>: Targeting Antibiofilm and Antivirulence Properties.","authors":"Amal F Makled, Azza Z Labeeb, Eman A E Badr, Amany M Abdelmaksoud, Safa R Elfiky, Asmaa K Amer, Asmaa S Sleem","doi":"10.1155/2024/8832448","DOIUrl":"https://doi.org/10.1155/2024/8832448","url":null,"abstract":"<p><p>The emergence of methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) several years ago highlighted the challenge of multidrug-resistant infections, emphasizing the critical need for innovative treatment approaches. Myrtenol, known for its antibacterial and antibiofilm properties, holds promise as a potential treatment option. This study aimed to evaluate the effectiveness of myrtenol against MRSA. The collected MRSA isolates were assessed for antimicrobial susceptibility following the Clinical and Laboratory Standards Institute (CLSI) guidelines 2023. Biofilm formation by MRSA was evaluated using the tissue culture plate (TCP) technique. The minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), and minimal biofilm inhibitory concentration (MBIC) of myrtenol against MRSA were determined both individually and in combination with antibiotics. Real-time PCR was employed to investigate the impact of myrtenol on the expression of virulence genes (sarA, agrA, and icaD) across the isolates. In this study, MRSA was identified in 90 out of 400 cases (22.5%) of hospital-acquired pathogens. Among the collected MRSA isolates, 53 out of 90 (59%) were found to produce biofilms. The MIC of myrtenol was comparable to the MBC across all tested isolates, they were almost the same. Combinations of myrtenol with most tested antibiotics exhibited synergistic effects exceeding 60%. Among the 53 biofilm-producing isolates, 45 isolates (85%) expressed the sarA gene, 49% expressed the agrA gene, and all biofilm-producing MRSA isolates (100%) expressed the icaD gene. A notable reduction in the relative quantity (RQ) values of virulence gene expression was observed after treatment with the MBIC of myrtenol across all tested isolates. Myrtenol demonstrated strong antimicrobial activity against MRSA, notably reducing the expression of key virulence genes linked to biofilm formation. This suggests its potential as a therapeutic agent for treating biofilm-associated MRSA infections.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"8832448"},"PeriodicalIF":2.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11498983/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142499981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of <i>Fusarium</i> Species and Determination of Their Toxins From Poultry Feeds During Storage.","authors":"Youssuf A Gherbawy, Abdullah Altalhi, Pet Ioan, Eman G A M El-Dawy","doi":"10.1155/2024/3474308","DOIUrl":"https://doi.org/10.1155/2024/3474308","url":null,"abstract":"<p><p>At a global scale, grains and poultry feeds are the primary sources of feed. Due to their considerable significance, any fungi capable of infecting these feedstuffs can pose a threat to both food safety and security. <i>Fusarium</i> spp. are a highly significant group of organisms. Fumonisins (FBs), deoxynivalenol (DON), trichothecene (T-2), and zearalenone (ZEN) are classifications of mycotoxins that are synthesized by <i>Fusarium</i> species. Their presence is associated with a range of factors that occur during growth, processing, and storage. We have recorded the high occurrence of <i>Fusarium</i> spp. in grains and poultry feeds in all tested samples. <i>Fusarium</i> (<i>F</i>) <i>oxysporum</i> was the most common species that appeared in all tested two hundred samples. FB1 was the predominant toxin that appeared with the highest concentration in 56 pellet samples with the range of 10.34-1043 <i>μ</i>g/kg. Also, it occurred with levels of 4.67-956 <i>μ</i>g/kg in the tested ingredients samples. <i>Fusarium verticillioides</i> isolates were the highest producers of FB1. <i>Fusarium</i> spp. isolates showed positive FB1 production with 84.6%, 82.5%, 82.2%, and 78.1%, isolated from pellet feed samples that were collected from Alhassa, Jeddah, Qassim, and Riyadh, respectively. 31.6%, 76.9%, 23.1%, 83.3%, and 88% of tested <i>Fusarium</i> spp. strains exhibited FB1 production in samples of barley, corn, sorghum, soybean, and wheat bran, respectively, with the range of 18-655 <i>μ</i>g/kg. Genes responsible for FB1, DON, T-2, and ZEN production were detected in the <i>Fusarium</i> spp. isolates.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"3474308"},"PeriodicalIF":2.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11557172/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibiotic Resistance and Virulence Factors in Clinical Isolates of <i>Stenotrophomonas maltophilia</i> from Hospitalized Patients in Tehran, Iran.","authors":"Mahrokh Bahrami, Narjess Bostanghadiri, Mehdi Goudarzi, Niloufar Khodaei, Ali Hashemi","doi":"10.1155/2024/8224242","DOIUrl":"https://doi.org/10.1155/2024/8224242","url":null,"abstract":"<p><p><i>Stenotrophomonas maltophilia</i> causes challenging infections in immunocompromised patients, exhibiting increasing resistance to multiple antimicrobials and possessing various virulence genes, including emerging resistance to trimethoprim-sulfamethoxazole. A total of 80 clinical isolates of <i>S. maltophilia</i> were collected from multiple hospitals in Tehran, Iran. This study conducted an analysis of antibiotic susceptibility by disc diffusion method and <i>E</i>-test assay, resistance and virulence gene frequencies were examined by PCR-sequencing, and multilocus sequencing typing (MLST) was performed for strain typing. Across the tested isolates, we observed notably high resistance rates for imipenem 80 (100%), meropenem 78(97.5%), and ceftazidime 72 (90%), while trimethoprim-sulfamethoxazole (SXT) showed a lower resistance rate of 2 (2.5%). Minocycline and levofloxacin demonstrated the highest susceptibility rates, with 70 (87.5%) and 80 (100%), respectively. The prevalence of antibiotic resistance genes bla _<i>L</i>1, and bla _<i>L</i>2 was 71 (88.75%) and 76 (95%), respectively. Additionally, the PCR analysis revealed that the frequency of virulence genes (<i>fliC</i>, <i>virB</i>, <i>papD</i>, <i>pilU</i>, <i>hlyIII</i>, <i>stmPr1</i>, and <i>stmPr2</i>) was 78 (97.5%), 77 (96.25%), 58 (72.5%), 77 (96.2%), 76 (95%), 31 (38.75%), and 80 (100%), respectively. Resistance to SXT isolate belong to the sequence type (ST15) and exhibits allelic profiles of (10, 29, 21, 21, 32, 32, and 10). The data obtained from our investigation have indicated that SXT remains an efficacious antibiotic and also highlighted the importance of effective management, identification of resistant isolates, and typing methods to address the global prevalence of antibiotic resistance in <i>S. maltophilia</i>.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"8224242"},"PeriodicalIF":2.8,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461076/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and Evaluation of In-House ELISAs for the Detection of SARS-CoV-2-Specific Antibodies in COVID-19 Patients in Sri Lanka.","authors":"Sisira L Pathirana, Bhagya Deepachandi, Peshala Gunasekara, Narmada Fernando, Inoka C Perera, Dakshika Gangani, James Thambyarajah, Dhanushka Dasanayake, Rajiva de Silva, Sunil Premawansa, Andreas Nitsche, Shiroma M Handunnetti","doi":"10.1155/2024/1331067","DOIUrl":"https://doi.org/10.1155/2024/1331067","url":null,"abstract":"<p><p>COVID-19 serological tests complement the molecular diagnostics and can be used as important tool for serosurveillance and vaccine efficiency evaluation. The aim of this study was to develop and evaluate the diagnostic performance of an in-house ELISA for retrospective serosurveillance of SARS-CoV-2. Total IgG and IgM levels in sera of PCR positive SARS-CoV-2 patients (<i>n</i> = 50) from North Colombo Teaching Hospital were evaluated and compared with sera (<i>n</i> = 50) collected from prepandemic healthy individuals as controls. Patient sample collection was initiated before vaccination programme was widely started within the country. Seropositivity of 94.0% (<i>n</i> = 47/50) was observed for either IgG or IgM anti-SARS-CoV-2 antibodies against receptor binding domain of spike protein or nucleocapsid protein in confirmed cases while none of controls were seropositive. In contrast, the seropositivity of only 48.0% (<i>n</i> = 24/50) was demonstrated with commercial ELISA kits for detection of IgG or IgM. All samples detected seropositive by commercially available kits remained seropositive with either in-house IgM or IgG ELISA. Significant correlations (<i>p</i> ≤ 0.001) were observed between Ab levels and day of sampling from the onset of illness. The overall sensitivity values of the in-house assays were 66.7%, 96.9%, and 100.0% for the first, second, and third week or longer after onset of symptoms for either in-house IgM or IgG ELISAs. Majority of the patients (>80.0%) were seropositive, regardless of age (<60 vs. >60 years), gender (male vs. female), or clinical severity (mild vs. moderate/severe). These data suggest that the developed in-house ELISAs can be applied to assess anti-SARS-CoV-2 antibody levels induced by either natural infections or vaccination.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"1331067"},"PeriodicalIF":2.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11427722/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seroepidemiological Survey on Bluetongue Virus (BTV) among Cattle, Sheep, and Goats in Gadarif State, Eastern Sudan.","authors":"Hatim H Abraheem, Mohammed O Hussien, Amira M Elhassan, Khalid A Enan, Azza B Musa, Selma K Ahmed, Abdel Rahim M El Hussein","doi":"10.1155/2024/7712412","DOIUrl":"https://doi.org/10.1155/2024/7712412","url":null,"abstract":"<p><p>Bluetongue (BT) is an arthropod-borne viral disease that primarily affects ruminants in tropical and temperate regions. In the present study, a cross-sectional survey was conducted to define the seroprevalence of Bluetongue virus and to identify the possible risk factors correlated with BTV seropositivity among cattle, sheep, and goats during the period 2015-2016 in Gadarif State. A total of 420 cattle, 877 sheep, and 641 goat serum samples were collected randomly from 12 localities. Information about age, sex, breed, area ecology, and location was obtained for each sample. Bluetongue seroprevalence was estimated using competitive enzyme-linked immunosorbent assay (cELISA). The overall seroprevalence of BTV was 92.9% (390/420), 76.4% (670/877), and 85.3% (547/641) among cattle, sheep, and goats, respectively. Multivariate analysis followed univariate analysis showed that there was a significant difference (<i>p</i> < 0.05) between location, area ecology and age groups of cattle, sheep, and goats, and seropositivity to BTV. In addition, a significant association (<i>p</i> < 0.05) was observed between sex and seropositivity to BTV in sheep. In conclusion, BTV antibodies are highly prevalent in Gadarif State and susceptible livestock are at risk of exposition with BTV. Consequently, these animals have protection against specific BTV serotypes.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"7712412"},"PeriodicalIF":2.8,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11424855/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence, Antibiotic Susceptibility Pattern and Associated Factors of <i>Streptococcus pyogenes</i> among Pediatric Patients with Acute Pharyngitis in Sidama, Southern Ethiopia.","authors":"Alemitu Beyene Gebre, Demissie Assegu Fenta, Abel Abera Negash, Betelihem Jima Hayile","doi":"10.1155/2024/9282571","DOIUrl":"https://doi.org/10.1155/2024/9282571","url":null,"abstract":"<p><strong>Background: </strong><i>Streptococcus pyogenes</i> is the most frequent cause of pharyngitis and skin infections in children and causes immune complications like rheumatic fever and rheumatoid heart disease (RHD), particularly in developing countries like Ethiopia. The aim of this study was to determine the prevalence, antibiotic resistance pattern, and associated factors of <i>Streptococcus pyogenes</i> among pediatric patients suspected of acute pharyngitis in Sidama Region, Southern Ethiopia.</p><p><strong>Methods: </strong>A cross-sectional study was conducted on 213 acute pharyngitis suspected pediatric patients from April to September 2022 at Hawassa University Compressive Specialized Hospital and Yirgalem Hospital. Sociodemographic and clinical data were collected using a structured questionnaire. A throat swab was cultured to isolate <i>S</i>. <i>pyogenes</i>, and antimicrobial susceptibility testing was done using standard bacteriological techniques. Data were analyzed using SPSS version 25, and <i>P</i> value of <0.05 was considered as statistically significant.</p><p><strong>Result: </strong>Out of 213 throat swabs cultured, 22 (10.3%) with 95% CI (6.6-14.6%) were <i>S</i>. <i>pyogenes</i> positive. All isolates of <i>S</i>. <i>pyogenes</i> were sensitive to penicillin and amoxicillin. In contrast, 8 (36.4%) isolates exhibited resistance to tetracycline, 7 (31.8%) to ceftriaxone, 6 (27.3%) to erythromycin, and 5 (22.7%) isolates showed multidrug resistance. The presence of palatal petechiae (<i>P</i>=0.037) and tonsillar swelling or exudate (<i>P</i>=0.007) were significantly associated with <i>S</i>. <i>pyogenes</i> carriage in children suspected of having acute pharyngitis.</p><p><strong>Conclusion: </strong>In this study, the prevalence of <i>S</i>. <i>pyogenes</i> among children suspected with acute pharyngitis was low compared to other studies. The isolates showed a high level of resistance to commonly used antibiotics. Therefore, the treatment of pediatric acute <i>S</i>. <i>pyogenes</i> pharyngitis should depend on an antimicrobial susceptibility test. Furthermore, evaluation of <i>S</i>. <i>pyogenes</i> pediatric acute pharyngitis risk factors and tracking of antibiotic resistance are crucial in the controlling of pediatric acute <i>S</i>. <i>pyogenes</i> pharyngitis.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"9282571"},"PeriodicalIF":2.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11421939/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Avian Infectious Bronchitis Virus: Molecular Detection in Southwestern Ethiopia Chickens.","authors":"Bezina Arega Emeru, Haregawi Tesfaye Desta","doi":"10.1155/2024/6979448","DOIUrl":"10.1155/2024/6979448","url":null,"abstract":"<p><p>Infectious bronchitis virus (IBV) is a significant threat to poultry worldwide, but its status in Ethiopia remains understudied. Thus, this study aimed to detect the virus and associated risk factors in South West Ethiopia. Ninety oropharyngeal swab samples were purposively collected from symptomatic chickens located in Jimma town, Seqa Chekorsa, and Tiro Afeta woredas of the Jimma zone between November 2021 and April 2022 to detect IBV virus by using RT-PCR. A side-by-side questionnaire was administered to assess risk factors. Total RNA was extracted, reverse transcription polymerase chain reaction (RT-PCR) was conducted, and products were visualized under UV light. The overall proportion of IBV was 16.6% (15/90). No statistical association was observed between any of the animal risk factors and the detection of the virus (<i>P</i>=0.57, 0.586, and 1). However, the proportion of birds infected by the virus was higher in males, exotic breeds, and adults compared to females, local breeds, and young birds. Similarly, none of the management risk factors had a significantly different effect on virus detection (<i>P</i>=0.25, 0.09, 0.088, and 0.726). However, improper carcass disposal (OR = 0.43, 95% CI: 0.13-1.4), lack of veterinary services (OR = 2.7, 95% CI: 0.8-8.3), and the presence of wild birds/rodents (OR = 4.4, 95% CI: 0.88-22.3) were associated with increased IBV risk but not cleaning of feeders/drinkers (OR = 1.1, 95% CI: 0.2-4.8). These findings underscore the need for enhanced biosecurity practices and further research to implement informed IBV control strategies in Ethiopia.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"6979448"},"PeriodicalIF":2.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11416162/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142286481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Characterization and Antibacterial Potential of Endophytic Fungal Isolates from Selected Mangroves along the Coastline of Kenya.","authors":"Teresia Nyambura Wacira, Huxley Mae Makonde, Carren Moraa Bosire, Cromwell Mwiti Kibiti","doi":"10.1155/2024/1261721","DOIUrl":"https://doi.org/10.1155/2024/1261721","url":null,"abstract":"<p><p>The increasing emergence and re-emergence of resistant pathogenic microbes causes a health threat to the human population. Scientists have been striving to find novel bioactive compounds and drugs to overcome these obstacles. This study aimed to characterize mangrove endophytic fungi and evaluate their antibacterial activity. <i>Heritiera littoralis</i>, <i>Rhizophora mucronata, Bruguiera gymnorrhiza</i>, <i>Avicennia marina,</i> and <i>Xylocarpus granatum</i> species were collected from Tudor Creek, Mida Creek, and Gazi Bay. A total of 30 fungal isolates were subjected to molecular identification based on analysis of their ITS gene region. The isolates in the inferred phylogenetic trees were affiliated with the genus <i>Aspergillus</i>. Ethyl acetate and butanol crude extracts of 38.2% of the 76 isolated fungal endophytes and eight mycelia samples were screened for antibacterial activity against <i>Staphylococcus aureus</i> (ATCC 27853), <i>Escherichia coli</i> (ATCC 25922), and <i>Pseudomonas aeruginosa (</i>ATCC 25923) using the disc diffusion method. <i>A. marina</i> and <i>R. mucronata</i> harbored the most fungal endophytes that showed the highest antibacterial activity. Seven fungal broth extracts exhibited higher antibacterial activities against the tested microorganisms than the positive control. The minimum inhibitory concentration (MIC) activity for the isolates demonstrated that the ethyl acetate extract of a root endophytic fungal isolate (RC6) (3.31 ± 0.01) of <i>A. marina</i> is a strong inhibitor since it showed significantly lower MIC activity compared to the positive control (3.84 ± 0.00) against <i>Pseudomonas aeruginosa</i> (<i>P</i> < 0.05). Therefore, this study confirms that mangrove species harbor fungal isolates that have antibacterial activity and hence could serve as a novel source of antibiotics. It is recommended that the pure compounds from these extracts be isolated for further bioactivity tests and structural elucidation for consideration as lead molecules in drug discovery. In addition, the genes responsible for the enhanced bioactivity in these isolates can be characterized and bioengineered for pharmaceutical application.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"1261721"},"PeriodicalIF":2.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11398959/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142286482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation and Characterization Identification of Edophytic Nitrogen-Fixing Bacteria from Peanut Nodules.","authors":"Nguyen Van Chuong, Tran Le Kim Tri","doi":"10.1155/2024/8973718","DOIUrl":"10.1155/2024/8973718","url":null,"abstract":"<p><p>This work was carried out to isolate and perform molecular identification and selection of endophytic nitrogen-fixing bacteria (ENFB) to be utilized as biofertilizer. In this research, nodulous samples of peanuts were collected from inside dyke areas, namely, Phuoc Hung of An Phu, An Giang, Vietnam. Ten colonies were isolated from nutrient agar plates containing YMA's medium. All isolates were rod shaped, Gram negative, and no spore creation. Biochemical tests indicated that they were obligate aerobes, catalase, oxidase, urea hydrolysis, well motile ability, and no nitrate reduction. The salt tolerance observed that most survived at 0.5% and 2% salinity (except <i>Enterobacter cloacae</i> subsp. <i>dissolvens</i> strain LMG 2683), while at 4%, only 3 isolates (<i>Bacillus aryabhattai</i> strain CM44<i>, Enterobacter asburiae</i> strain IIWM-JS-07L, and <i>Bacillus songklensis</i> strain KCa6) and at 5% only, 2 isolates survived, namely, <i>Enterobacter asburiae</i> strain IIWM-JS-07L and <i>Bacillus songklensis</i> strain KCa6. The result showed that most of ten ENFB strains could adapt to the range of 25°C and 45°C (except <i>Enterobacter cloacae</i> subsp. <i>dissolvens</i> strain LMG 2683 and Enterobacter mori strain cjy13 at 25°C). Out of ten isolates, three were finally selected for the next studies, which potentially have N-fixing ability and are utilized as biofertilizer in agricultural cultivation.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2024 ","pages":"8973718"},"PeriodicalIF":2.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380715/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142153997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}