BMC Microbiology最新文献

{"title":"Impact of heavy metals on antibiotic resistance of Escherichia coli from slum wastewater in Kawempe division, Kampala district, Uganda: a case study.","authors":"Isaac Byarugaba, Alice Nabatanzi, Emmanuel Muhumuza, Joseph Kyambadde","doi":"10.1186/s12866-025-04024-1","DOIUrl":"10.1186/s12866-025-04024-1","url":null,"abstract":"<p><strong>Background: </strong>Slum dwellers face significant infrastructure and public health challenges like poor housing and drainage, inadequate sanitation, and limited access to clean water, leading to increased disease transmission and resistance to antibiotic treatments. This study evaluated the impact of heavy metals on antibiotic resistance patterns of Escherichia coli in wastewater from slums of Bwaise II, Bwaise III, Kazo, and Makerere III in Kawempe division, Kampala.</p><p><strong>Methods: </strong>Levels of heavy metals (lead, mercury, cadmium, chromium, and arsenic) in wastewater were determined using inductively coupled plasma mass spectroscopy. Escherichia coli were isolated from wastewater using MacConkey agar and their susceptibility to 50 µl of stock antibiotics (tetracycline, amoxicillin, ceftriaxone at 30 µg/ml, and ciprofloxacin at 5 µg/ml) determined. The potential of heavy metals to induce antibiotic resistance in Escherichia coli was determined by culturing susceptible isolates in 200 µl of Luria-Bertina broth containing stock antibiotics (10 µl), or stock antibiotics (10 µl) and stock heavy metals (10 µl). Stock heavy metals were prepared from the average concentration of heavy metals detected in wastewater.</p><p><strong>Results: </strong>Detectable levels of heavy metals were reported in wastewater from Bwaise II, Kazo and Makerere III only. Lead, cadmium and arsenic, mercury and chromium, were highest in Bwaise II, Kazo, and Makerere III, respectively. The occurrence of Escherichia coli resistant to at least an antibiotic was 72.8% (169 of 232) and resistance to tetracycline, ceftriaxone, amoxicillin, and ciprofloxacin were 34.1%, 28.9%, 35.3%, and 34.5%, respectively. Study findings further revealed a positive correlation (R² = 0.371-0.985) between the presence of heavy metals in wastewater and antibiotic resistance patterns of Escherichia coli. Also, heavy metals; lead (77.41 µg/ml), mercury (1.44 µg/ml), and cadmium (10.21 µg/ml) significantly (p < 0.05) induced antibiotic resistance in susceptible Escherichia coli.</p><p><strong>Conclusion: </strong>Wastewater in Kawempe slums is polluted with heavy metals and high prevalence of antibiotic-resistant Escherichia coli. Inadequate infrastructure in slums facilitate discharge of wastewater polluted with heavy metals, which in turn play a role in increasing antibiotic resistance. There is need for proper wastewater management to contain the prevalence of antibiotic resistance.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"310"},"PeriodicalIF":4.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12093770/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emergence of linezolid-resistant Enterococcus cecorum clade F harboring optrA/fexA causing enterococcal spondylitis in commercial broilers in China.","authors":"Fanrun Meng, Defang Zhou, Ruiqi Li, Feng Lang, Bin Xiang, Liangyu Yang, Ziqiang Cheng","doi":"10.1186/s12866-025-04045-w","DOIUrl":"10.1186/s12866-025-04045-w","url":null,"abstract":"<p><strong>Background: </strong>Enterococcus cecorum, long regarded as a commensal bacterium in the avian gut, has recently emerged as a significant pathogen causing enterococcal spondylitis. The widespread use of antibiotics has driven the emergence of multidrug resistance in Enterococcus, particularly linezolid-resistant strains, posing risks to poultry farming and public health. Here, we report the first isolation and characterization of a linezolid-resistant E. cecorum strain (2023EC-GS-SDAU-1) harboring the optrA/fexA resistance gene cluster from Chinese commercial broilers, and analyze its genomic profile, resistance mechanisms, and pathogenicity.</p><p><strong>Results: </strong>Whole-genome sequencing identified 15 resistance genes, including optrA, fexA, catA8, SAT-4, AAC(6')-Ie-APH(2'')-Ia, and aad(6)-all newly identified in E. cecorum. The optrA/fexA/ermA cluster colocalized on chromosomal genomic island GI12 is flanked by codirectional insertion sequences (ISEfa5), forming a mobile transposon-like unit. Phylogenetic analysis placed the strain within clade F, closely related to pathogenic isolates from the U.S. and France. Antimicrobial susceptibility testing confirmed multidrug resistance to aminoglycosides, macrolides, florfenicol, and linezolid. Additionally, 31 virulence genes were identified, and experimental infections in broilers recapitulated spondylitis lesions, validating pathogenicity.</p><p><strong>Conclusion: </strong>This study is the first to characterize a linezolid-resistant E. cecorum strain harboring the optrA/fexA cluster in poultry in China, implicating ISEfa5-mediated mobilization in resistance dissemination. The findings underscore the poultry production chain as a critical reservoir for oxazolidinone resistance (optrA) and highlight urgent needs for enhanced surveillance to mitigate zoonotic risks.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"313"},"PeriodicalIF":4.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12093769/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green synthesis of silver nanoparticles using Sudanese Candida parapsilosis: a sustainable approach to combat antimicrobial resistance.","authors":"Nesreen A A Ibrahim, Humodi A Saeed, Samar M Saeed, Osama Mohamed, Omnia H Suliman, Sabah A E Ibrahim, Sofia B Mohamed","doi":"10.1186/s12866-025-04038-9","DOIUrl":"10.1186/s12866-025-04038-9","url":null,"abstract":"<p><strong>Background: </strong>Antimicrobial resistance (AMR) is a critical global health challenge, particularly in Sudan, where the overuse and misuse of antibiotics have driven the rise of multidrug-resistant (MDR) pathogens. Conventional antimicrobial strategies often fall short due to rapid resistance development and limited efficacy, highlighting the need for novel approaches. Nanotechnology offers promising alternatives, with silver nanoparticles (AgNPs) demonstrating potent broad-spectrum antimicrobial activity. This study aims to develop an eco-friendly synthesis of AgNPs using Candida parapsilosis (C. parapsilosis), an untapped yeast strain isolated from Sudanese soil, to combat AMR.</p><p><strong>Results: </strong>Biosynthesis of AgNPs using C. parapsilosis was successfully confirmed through UV-Vis spectroscopy, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM), revealing well-defined nanoparticles. The biosynthesized AgNPs exhibited strong antibacterial activity against both ATCC reference strains and MDR clinical isolates of Gram-positive and Gram-negative bacteria, with inhibition zones increasing in a concentration-dependent manner. At optimal concentrations, inhibition zones reached 29 mm for Pseudomonas aeruginosa (P.aeruginosa) (ATCC 27853), while clinical isolates of Salmonella typhi (S. typhi) (24.5 ± 0.58 mm) and Escherichia coli (E. coli) (23.8 ± 0.79 mm) exhibited significant susceptibility. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays demonstrated potent bactericidal activity, particularly against E. coli and Klebsiella pneumoniae (K. pneumoniae) at 0.3125 mg/mL. Furthermore, AgNPs synergistically enhanced the efficacy of conventional antibiotics in a species- and antibiotic-dependent manner. The strongest synergy was observed in Enterococcus faecalis (E. faecalis) (up to 9.84-fold with Colistin) and Acinetobacter baumannii (A. baumannii) (up to 5.11-fold with Ceftazidime), suggesting that AgNP-enhanced antibiotic efficacy varies depending on bacterial species, nanoparticle synthesis method, and antibiotic type.</p><p><strong>Conclusions: </strong>This study presents a novel and sustainable approach to tackling AMR by leveraging Sudanese yeast strains for the green synthesis of AgNPs. The findings underscore the potential of AgNPs as an effective antibacterial agent, both independently and in combination with conventional antibiotics, to combat MDR pathogens. By integrating microbiology and nanotechnology, this research offers a cost-effective and environmentally friendly solution for AMR mitigation. These findings provide a strong foundation for future clinical applications and public health interventions, particularly in resource-limited settings.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"312"},"PeriodicalIF":4.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12093675/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-alcoholic fatty liver disease enhances the beneficial effect of renal denervation on gut microbiota aberrations in rats with heart failure.","authors":"Fuyan Chen, Zhiqin Guo, Yufeng Chen, Shun Li, Pingan Chen","doi":"10.1186/s12866-025-04027-y","DOIUrl":"10.1186/s12866-025-04027-y","url":null,"abstract":"<p><strong>Background: </strong>Renal denervation (RDN) contributes to improving cardiac function by ameliorating aberrations of the gut microbiota, and non-alcoholic fatty liver disease (NAFLD) is associated with gut microbiota dysbiosis and is critically involved in the development of heart failure (HF). It is unclear whether the beneficial effect of RDN on gut microbiota in HF can be affected by NAFLD and whether this effect changes with the severity of NAFLD.</p><p><strong>Methods: </strong>HF Sprague Dawley rats induced by transverse aortic constriction were fed a high-fat-fructose diet and underwent RDN, and sequencing of 16S rRNA gene in fecal samples was detected.</p><p><strong>Results: </strong>The dissimilarity coefficients and sample distances of the intestinal microbiome were elevated in HF rats with NAFLD. After RDN, HF rats with NAFLD had fewer bacteria harmful to cardiac function, such as Alphaproteobacteria, Bacteroidota and Prevotella-9, and more bacteria beneficial to HF, such as Monoglobaceae, Proteobacteria and Monoglobales, than HF rats without NAFLD (all p < 0.05). This tendency also existed but was much less significant when compared between HF rats with non-alcoholic steatohepatitis (NASH) and without NAFLD. Predictive functional profiling of microbial communities revealed that after RDN, the abundance of membrane transport, environmental and genetic information processing was significantly higher, and glycan biosynthesis and metabolism was significantly lower in HF rats with NAFLD than in those without NAFLD.</p><p><strong>Conclusion: </strong>NAFLD could further enhance the beneficial role of RDN in mitigating gut microbiota aberrations in HF rats by increasing beneficial bacteria and decreasing bacteria harmful to cardiac function, but this effect was not apparent in NASH rats.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"311"},"PeriodicalIF":4.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12093722/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mycobacteroides abscessus subspecies: a comparative genomic analysis reveals unique metabolic activities and drug resistance patterns.","authors":"Xiaoyu Wang, Yongdong Dai, Xiao Wang, Lingfei Li, Yanhai Feng, Shunying Liu, Zhenyu Kou, Liang Wang, Fangjie Wang, Yaokai Chen, Xia Lei","doi":"10.1186/s12866-025-04010-7","DOIUrl":"10.1186/s12866-025-04010-7","url":null,"abstract":"<p><strong>Background: </strong>Mycobacteroides abscessus poses a considerable and growing threat to public health due to its resistance against most antibiotics and low cure rate. For a comprehensive understanding of the genomic characteristics and drug resistance mechanisms of M. abscessus, clinical isolates from diverse sources were collected and analyzed.</p><p><strong>Results: </strong>The clinical M. abscessus complex analyzed herein primarily comprised two subspecies: Mycobacteroides abscessus subsp. abscessus and Mycobacteroides abscessus subsp. massiliense. Furthermore, comparative genomic and single nucleotide polymorphism analyses revealed distinct metabolic activities among subspecies. Subsequent examination of core hub gene mutations confirmed the presence of distinct metabolic and biosynthetic pathways between M. abscessus subspecies, which may have contributed to their differential drug resistance and may aid in providing targeted interventions. Understanding this subtle genomic variation is crucial for improving treatment strategies and patient outcomes. Additional analyses identified potential novel amikacin and moxifloxacin resistance genes, offering a promising avenue for investigating M. abscessus drug resistance.</p><p><strong>Conclusions: </strong>Through comparative genomic analysis, we revealed the unique metabolic activities of M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, providing a scientific basis for future diagnostic and personalized management strategies. Identifying possible novel amikacin and moxifloxacin resistance genes within these subspecies offers insights for future drug development efforts and enhances our understanding of the mechanisms underlying M. abscessus drug resistance.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"308"},"PeriodicalIF":4.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12090666/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"D-optimal design model and biosynthetic pathway for gentamicin production by Micromonospora purpureochromogenes NRRL B-16094.","authors":"Muath Suliman, Amr S Bishr, Sally T K Tohamy, Mohammad Y Alshahrani, Khaled M Aboshanab","doi":"10.1186/s12866-025-04001-8","DOIUrl":"10.1186/s12866-025-04001-8","url":null,"abstract":"<p><strong>Background: </strong>Micromonospora purpureochromogenes NRRL B-16094, a natural producer of gentamicin (GEN), a 5,6-diglycosylated 2-dexoystreptamine-aminoglycoside antibiotic (2DOS-AGA) broad-spectrum bactericidal activity. In literature, limited studies are concerned with the biosynthetic route and various cultural conditions influencing GEN production.</p><p><strong>Methods: </strong>Therefore, this study aimed to explore the GEN biosynthesis pathway and compare it to that of fortimicin and kanamycin. In addition, four key environmental conditions influencing GEN production were statistically optimized using response surface D-optimal design (DOD). Herein, the biosynthetic pathway of GEN was proposed based on the biochemistry of the identified genes/proteins within the gene cluster. Comparing the GEN-biosynthetic gene cluster to that of kanamycin and fortimicin suggested that gentamicin biosynthesis could have originated from a combination of biosynthetic pathways of both antibiotics.</p><p><strong>Results: </strong>For the optimization experiments, culture media 4 (CM4) and 6 (CM6) gave the highest specific productivity at 6.36 and 3.80 µg/mg, respectively. A DOD quadratic model was successfully generated to optimize four key environmental factors. Predicted and experimentally confirmed optimized factors were an initial pH of 7, an incubation temperature of 30˚C, and an agitation of 300 rpm for 10 days. This resulted in a 13.5-fold increase (289.5 µg/mL) over that produced by the basic CM1 production medium (21.4 µg/mL) and 2.4 times (over that obtained by CM4 (123.7 µg/mL) as verified by HPLC analysis.</p><p><strong>Conclusion: </strong>DOD is an efficient tool for optimizing GEN. Accordingly, the optimized conditions are highly advisable during the scaling up of GEN production by M. purpureochromogenes NRRL B-16094.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"309"},"PeriodicalIF":4.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12090562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144109716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prophylactic administration of overproducing-abscisic acid Bacillus licheniformis attenuated DSS-induced colitis in mice by regulating the gut microbiota and immune activity.","authors":"Zeyan Xu, Lijiang Zhao, Mengting Wu, Anqi Cui, Wei Chen, Guohao Zheng, Jingyi Zhou, Daqing Gao, Ruihua Shi","doi":"10.1186/s12866-025-03988-4","DOIUrl":"10.1186/s12866-025-03988-4","url":null,"abstract":"<p><strong>Background: </strong>Inflammatory bowel disease (IBD) involves the complex interplay among the mucosal barrier, microbiota, immunity and genetic factors. There are currently no satisfactory treatments for IBD. Administration of the probiotic Bacillus licheniformis (Bl) can improves colitis by regulating the gut microbiota. The phytohormone abscisic acid (ABA) treatment has favorable effects on immunity, as well as on inflammatory diseases like colitis. We hypothesized that the expression of an additional cyp gene by the Bl to increase its ABA production would enhance its effects.</p><p><strong>Results: </strong>In this study, we found that a Bl-cyp strain overexpressing the cyp gene secreted more ABA into its supernatant than either the parental Bl stain or a Bl-pET82a strain expressing only a vector pET82a when these bacteria were grown in Nfb medium for 48 h. The prophylactic administration of the Bl-cyp strain culture more effectively attenuated dextran sodium sulfate (DSS)-induced colitis in mice compared to the Bl and Bl-pET28a strains. These findings were associated with significantly reduced epithelial barrier damage, as well as increased number of goblet cells and expression levels of occludin gene in the colonic epithelial layer, and decreased serum LPS levels in the Bl-cyp group. In addition, the administration of Bl-cyp strain effectively regulated the disordered gut microbiota by improving their diversity, richness and compositions more than the Bl or Bl-pET82a strain, including the ratio of Bacteroidota: Bacillota. It also inhibited the excessive growth of opportunistic pathogen Escherichia just like the Bl or Bl-pET82a strain. Moreover, the preventive administration of the Bl-cyp strain to mice following DSS-induced colitis enhanced the proportion of Treg cells and suppressed the proportion of Th17 cells in mesenteric lymph nodes (MLNs), decreased the levels of pro-inflammatory cytokines TNF-α, IL-6, and IL-22, and increased the level of anti-inflammatory IL-10 in colon tissues, similar to treatment with a high concentration of the ABA standard (ABA-H). Notably, the treatment with the Bl-cyp strain more effectively regulated the disordered microbiota than the ABA-H.</p><p><strong>Conclusions: </strong>The administration of the Bl-cyp strain may provide a novel preventive approach for IBD, and may exert its effects by modulating the gut microbiota and host's immune status.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"306"},"PeriodicalIF":4.0,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12087060/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization and characterization of polyhydroxybutyrate produced by Halomonas meridiana using orange peel waste.","authors":"Mahmoud H Hendy, Amr M Shehabeldine, Amr H Hashem, Ahmed F El-Sayed, Hussein H El-Sheikh","doi":"10.1186/s12866-025-04007-2","DOIUrl":"10.1186/s12866-025-04007-2","url":null,"abstract":"<p><p>The production of bioplastics from marine microorganisms is significantly relevant in the field of biotechnological applications for sustainable ecological management. Nevertheless, the expense associated with PHB production is substantial and regarded as the primary obstacle to its industrialization. In this study, orange peel waste served as a carbon source to enhance PHB production efficiency. Among the 15 strains evaluated, MH 96 was selected for PHB production due to its high salt tolerance and efficient utilization of orange peel as a substrate. The highest producing PHB strain MH96 was genetically identified using 16S rRNA sequencing as Halomonas meridiana and submitted in the GenBank under accession numbers PP826284. The optimal fermentation conditions were evaluated through single-factor optimization. Upon completion of the response surface optimization, the Plackett-Burman and Box-Behnken design experiments were conducted utilizing the outcomes of the single-factor optimization. The final parameters were the inoculum size of 1.74, (NH₄)₂HPO₄ concentration of 1.0 and pH 6.37, and PHB yield of 5.94 g/L. The characterization of the extracted biopolymer by NMR, FTIR, XRD, and thermal properties was used to examine the properties of the extracted PHB, and gas chromatography-mass spectrometry (GC-MS) proves the presence of 2-butenoic acid, 1-methyl ethyl ester, tetradecane, hexadecanoic acid, methyl ester, and docosanoic acid, 8,9,13-trihydroxy-. Methyl ester, which confirmed the structure of the polymer as PHB.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"304"},"PeriodicalIF":4.0,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12087205/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144092782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prebiotic potential of oligosaccharides extracted from improved Ugandan varieties of millet, sesame, soybean, and sorghum: enhancing probiotic growth and enteric pathogen inhibition.","authors":"Docus Alowo, Solomon Olum, Ivan Muzira Mukisa, Duncan Ongeng","doi":"10.1186/s12866-025-04028-x","DOIUrl":"10.1186/s12866-025-04028-x","url":null,"abstract":"<p><p>Functional gastrointestinal disorders like diarrhea continue to affect children under five years in low-income countries. Incorporating health-enhancing bioactive compounds such as prebiotics in diet offers a promising solution. This study investigated prebiotic potential of oligosaccharides extracted from improved varieties of millet (Seremi 2, Naromil 2), sesame (Sesim 2, Sesim 3), soybean (Maksoy 3N, Maksoy 6N), and sorghum (Narosorg 2, Narosorg 4), commonly consumed in Uganda. These were compared to their respective indigenous variety. This study employed standardized methods for optical density measurement, culture preparation, and oligosaccharide extraction to evaluate prebiotic properties. We investigated whether plant-based oligosaccharides could enhance the effectiveness of probiotics, specifically Lactiplantibacillus plantarum (ATCC 14917) and Lacticaseibacillus rhamnosus (ATCC 7469), in antagonizing common enteric pathogens (Salmonella enterica subsp. enterica (ATCC 13076) and Shigella flexneri (ATCC 12022)). Approximately 4-8 log CFU/ml of each probiotic was incubated in 2% w/v oligosaccharide extracts at 37 °C to evaluate the influence of the extracts on their growth, short-chain fatty acid (SCFA) production and antagonistic activity. Maximum cell density, which exceeded the minimum recommended probiotic cell density (6 log CFU/ml), was achieved during 24-h incubation period. The probiotics exhibited optimal growth in extracts of Sesim 2, Maksoy 3N, Narosorg 2 and indigenous millet variety resulting in a 68-84% increase in cell densities. The concentration of SCFA concentration was significantly higher (p < 0.05) in soybean-based oligosaccharides. Both probiotics antagonized growth of Salmonella and Shigella by more than 40% when cultured on Sesim 2, Maksoy 3N, Narosorg 2 and indigenous millet variety, while maintaining the probiotic cell densities above the minimum recommended level. These varieties show great potential as functional ingredients for developing synbiotic-rich foods to promote gut and public health. However, to evaluate the oligosaccharides prebiotic efficacy, in vitro fermentation using fecal microbiota and in vivo studies are necessary to determine gut microbiota changes and interactions.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"307"},"PeriodicalIF":4.0,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12087199/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The efficacy of nanoparticles on soil microbial biodiversity and the prevention of Fusarium wilt disease (Fusarium oxysporum f.sp. lycopersici).","authors":"Tahsin Shoala, Hoda A S El-Garhy, Nevein A S Messiha, Sozan E El-Abeid","doi":"10.1186/s12866-025-04022-3","DOIUrl":"10.1186/s12866-025-04022-3","url":null,"abstract":"<p><p>Fusarium oxysporum f.sp. lycopersici (FOL) wilt endangers Egyptian tomato productivity. Nanotechnology has emerged as an efficient tool for managing plant diseases. This study evaluated salicylic acid nanoparticles (SA-NPs) and glycyrrhizic acid ammonium salt nanoparticles (GAS-NPs) against F. oxysporum in vitro. SA-NPs reduced F. oxysporum growth by 37.8%, and GAS-NPs by 18.9% at 3 ml/L, while SA-NPs at high doses significantly reduced the bacterial count in the tomato rhizosphere. Under greenhouse conditions, high doses of SA-NPs suppressed disease by 73%, compared to 87-93% for other treatments, coinciding with a significant decrease in the overall bacterial count in the tomato rhizosphere. A high dose of SA-NPs reduced heterotrophic, copiotrophic, and fluorescent pseudomonads in the tomato rhizosphere but did not affect the total number of fungi. In vitro, a high dose of both nanoparticles did not significantly reduce bacterial growth in four tested strains: Leclercia adecarboxylata, Pseudomonas putida, Enterobacter ludwigii, and Bacillus marcorestinctum. This suggests that while SA-NP doesn't directly affect bacterial growth, it may interact with tomato roots, indirectly affecting the rhizosphere bacterial population. All treatments increased the expression of ethylene-responsive transcription factor 3 (RAP), xyloglucan endotransglucosylase 2 (XET-2), catalytic hydrolase-2 (ACS-2), phenylalanine ammonia-lyase 5 (PAL5), lipoxygenase D (LOXD), proteinase inhibitor II (PINII), and pathogenesis-related protein 1 (PR1). The highest gene expression levels were obtained from 1 ml/L GAS-NPs and SA-NPs field applications. Furthermore, SA-NPs at 1 ml/L were the most efficient in controlling tomato Fusarium wilt, followed by GAS-NPs. This study investigates the possibility of nanotechnology-based techniques for decreasing Fusarium wilt in tomatoes. However, because of the deleterious impact on the soil bacterial community, high dosages of NPs, particularly SA-NPs, should be applied with caution. Future research should focus on optimizing NPs doses to maintain a balance between efficient disease control and the maintenance of the beneficial complexity of soil microbial biodiversity.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"305"},"PeriodicalIF":4.0,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12087229/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144092784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}