Search Results (4,018)

Current diagnostic methods for bacterial infections in critically ill patients, including ventilator-associated pneumonia (VAP), are time-consuming, while empirical antibiotic therapy contributes to rising resistance. Bacteria-derived volatile organic compounds (VOCs) are being explored as specific biomarkers for pathogen identification and treatment monitoring. This study expands knowledge of Escherichia coli metabolism by identifying VOCs produced by both multidrug-resistant and susceptible strains, characterizing their temporal profiles during growth, and assessing VOC profile changes after imipenem exposure. Reference strains and 21 clinical isolates (derived from BAL samples of VAP patients) were cultured under controlled conditions. Headspace VOCs were preconcentrated using multibed sorption tubes and analyzed by gas chromatography–mass spectrometry (GC-MS), with compound identities confirmed using external standards. Sampling at seven time points over 24 h cultures revealed three VOC emission patterns: continuous release, temporary maximum, and compound uptake. In total, 57 VOCs were identified from the susceptible strain and 41 from the resistant one, with dimethyl disulfide, 2-butenal, ethyl acetate, and furan elevated in the resistant strain. Imipenem addition altered VOC production in the susceptible strain, with levels of six compounds elevated and seven reduced, while resistant profiles remained stable. Clinical isolates produced 71 VOCs, showing greater metabolic diversity and highlighting the relevance of isolate-derived VOCs in future studies. Full article

Lactic acid bacteria (LAB) are a promising source of postbiotics with potential applications in the cosmetic industry; however, strains isolated from fermented vegetables are rarely studied. This study aimed to characterize the bioactivity of postbiotics produced by Lactiplantibacillus pentosus B1 isolated from fermented beetroot juice. An organic extract (ELCFS) and a lyophilizate (LLCFS) were prepared from cell free supernatant of B1 and assessed for antimicrobial activity (MIC, MBC), biofilm inhibition and eradication ability against Staphylococcus aureus, Escherichia coli, Streptococcus pyogenes and Cutibacterium acnes. Stability (temperature, time) and cytotoxicity were also examined. Metabolite composition was determined by GC-MS. MIC values were 10 g/L for ELCFS and 10–20 g/L for LLCFS. ELCFS completely inhibited biofilm formation at 10 g/L, and LLCFS at 25 g/L; partial inhibition was observed at lower concentrations (e.g., E. coli—32.99% at 1 g/L ELCFS; S. aureus and S. pyogenes—74.01% and 95.67%, respectively, at 5 g/L). Complete eradication of mature biofilm was obtained at 2.5 g/L (ELCFS) and 12.5 g/L (LLCFS), while a significant partial effect was observed from 0.04 g/L ELCFS for E. coli (29.3%) and 0.2 g/L LLCFS for S. pyogenes (23.2%). C. acnes showed the lowest sensitivity. A reduction in viability of eucaryotic cells was observed at ≥ 5 g/L ELCFS (90.32%) and 12.5—50 g/L LLCFS (55.87—89.20%). Importantly, concentrations causing partial inhibition and eradication of biofilm did not show cytotoxicity towards fibroblasts. The preparations were thermostable and retained activity over time; only incubation of ELCFS at elevated temperature significantly reduced its antimicrobial activity against the C. acnes strain. GC-MS analysis revealed five organic acids, with lactic acid dominating. The results confirm the potential of L. pentosus B1 as a source of stable, effective, and safe postbiotics for cosmetology applications. Full article

Weeds are one of the main problems in cultivation of medicinal and aromatic plants (MAPs); they negatively affect yield (herba and essential oil), and the overall quantity and quality of biomass, flowers, roots, seeds, and secondary metabolites. This review evaluates mulching as a sustainable, non-chemical method for weed management in the cultivation of MAPs and examines how effectively organic, synthetic, and living mulches reduce weeds and increase yields. Regarding different mulch materials such as straw, sawdust, bark, needles, compost, polyethylene, and biodegradable films, the basic processes of mulch activity, including light interception, physical suppression, and microclimate adjustment, are examined. The review further analyzes the impact of mulching on soil parameters (moisture, temperature, pH, chlorophyll content) and the biosynthesis of secondary metabolites. The findings consistently indicate that mulching substantially reduces weed biomass, improves crop performance, and supports organic farming practices. However, there are still issues with cost, material availability, and possible soil changes, and the efficacy is affected by variables including cultivated plant species, mulch type, and application thickness. The review highlights the importance of further research to optimize the selection of mulch and MAPs and their application across various agroecological conditions, and indicates that mulching is a potential, environmentally friendly technique for weed control in MAP cultivations. Full article

Background: Nitrogen fixation (diazotrophy) is a desirable trait present in some cyanobacteria with potential applications in sustainable agriculture and chemical feedstock production. This study discovers a predictive relationship modeled between secondary metabolites and diazotrophic cyanobacteria by leveraging chemical structure similarity to identify diazotrophic strains. Methods: An algorithm was developed using chemical fingerprint similarity of metabolites curated from CyanoMetDB and evaluated with leave-one-out cross-validation on 133 manually labeled metabolites. Results: The model demonstrated strong predictive performance, achieving 88% accuracy and a ROC-AUC of 0.96. We then applied this approach to prioritize likely diazotrophic strains among 1980 unlabeled metabolites and their associated organisms, providing a rank order of most likely undetected diazotrophic strains. Toxicity analysis showed that diazotrophic-associated metabolites show similar toxicity to non-diazotrophic metabolites in rats, with less toxicity in Daphnia magna, suggesting that these metabolites are not playing a defensive role. However, these metabolites did have relatively high nitrogen presence, and many were cyclic peptides, potentially serving as signaling molecules. Conclusions: This study underscores the potential of secondary metabolites in identifying diazotrophs, even when they may not be actively demonstrating diazotrophic physiology. Discovering more diazotrophic cyanobacteria has strong implications for advancing agricultural biotechnology towards the goal of self-fertilizing crops. Full article

Potentially probiotic yeasts isolated from foodstuffs can be used as components in functional fermented beverages. To date, there have been no reports on the use of Saccharomyces cerevisiae var. boulardii, Pichia kudriavzevii, Metschnikowia pulcherrima, or Hanseniaspora uvarum isolates in the production of a traditional Polish beverage called underbeer (podpiwek). The aim of the study was to determine the usefulness of six isolates of the above-mentioned species as starter cultures for the fermentation of underbeer. First, the important characteristics of the yeasts, like ethanol tolerance and H₂S production, were examined. In the next stage, the wort was fermented by the tested yeasts, and cell viability, fermentation vigor, sugar assimilation, and production of metabolites, as well as properties of the beverage (pH, titratable acidity, color, and turbidity), were determined. Saccharomyces yeasts tolerated the addition of ethanol up to 16% (v/v), while Pichia, Metschnikowia, and Hanseniaspora tolerated up to 10% (v/v) ethanol, and all except H. uvarum produced H₂S. The yeasts remained viable in the beverages for 1 month at the required level, utilized glucose, fructose and partially complex carbohydrates, and produced ethanol (S. cerevisiae, P. kudriavzevii, and M. pulcherrima) and organic acids such as tartaric, malic, and citric acid. The underbeers became sour and showed varying turbidity and a color corresponding to pale-amber beers. All tested strains produced fermented beverages that were low- or non-alcoholic with different properties. This experiment may be a starting point for research into regional products as probiotic or synbiotic foods; however, further research is required for selection of the best strains for underbeer fermentation. Full article

Tomato fruit (Solanum lycopersicum) is a valuable agricultural crop worldwide due to its nutritional value and culinary applications, making it one of the most widely consumed vegetables in the human diet. However, excessive solar UV-B radiation represents a significant factor in decreasing productivity, marketable yields, and fruit quality in tomato crops by causing damage to both DNA and the photosynthetic system, as well as chlorophyll degradation. The application of silicon nanoparticles has been shown to increase tolerance to abiotic stressors, including enhanced UV-B radiation. Therefore, this study aims to evaluate the protective effects of foliar silicon nanoparticle (SiNP) application on photosynthetic parameters, photosynthetic pigments, and secondary metabolites under enhanced UV-B stress in tomato plants. Photosynthetic parameters (stomatal conductance to water vapor, net CO₂ assimilation rate, transpiration rate, and intercellular CO₂ molar fraction), biogenic volatile organic compounds (BVOCs), chlorophylls, and carotenoids were evaluated. The application of SiNPs showed beneficial effects on plants grown under ambient UV-B conditions, increasing photosynthetic parameters while also enhancing chlorophyll and carotenoid levels. In plants exposed to enhanced UV-B radiation, SiNP treatment helped to maintain and even improve photosynthetic parameters and stomatal function in leaves while also promoting the accumulation of photosynthetic pigments. Additionally, the application of SiNPs also resulted in a slightly higher content of lycopene and total carotenoids in tomato fruits. Full article

Type 2 diabetes (T2D) is a complex metabolic disease characterized by chronic hyperglycemia due to insulin resistance and inadequate insulin secretion. Beyond the classically implicated organs, emerging evidence highlights the gut as a central player in T2D pathophysiology through its interactions with metabolic organs. The gut hosts trillions of microbes and enteroendocrine cells that influence inflammation, energy homeostasis, and hormone regulation. Disruptions in gut homeostasis (dysbiosis and increased permeability) have been linked to obesity, insulin resistance, and β-cell dysfunction, suggesting multifaceted “Gut-X axes” contribute to T2D development. We aimed to comprehensively review the evidence for gut-mediated crosstalk with the pancreas, endocrine system, liver, and kidneys in T2D. Key molecular mechanisms (incretins, bile acids, short-chain fatty acids, endotoxins, etc.) were examined to construct an integrated model of how gut-derived signals modulate metabolic and inflammatory pathways across organs. We also discuss clinical implications of targeting Gut-X axes and identify knowledge gaps and future research directions. A literature search (2015–2025) was conducted in PubMed, Scopus, and Web of Science, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews). Over 150 high-impact publications (original research and review articles from Nature, Cell, Gut, Diabetologia, Lancet Diabetes & Endocrinology, etc.) were screened. Data on gut microbiota, enteroendocrine hormones, inflammatory mediators, and organ-specific outcomes in T2D were extracted. The GRADE framework was used informally to prioritize high-quality evidence (e.g., human trials and meta-analyses) in formulating conclusions. T2D involves perturbations in multiple Gut-X axes. This review first outlines gut homeostasis and T2D pathogenesis, then dissects each axis: (1) Gut–Pancreas Axis: how incretin hormones (GLP-1 and GIP) and microbial metabolites affect insulin/glucagon secretion and β-cell health; (2) Gut–Endocrine Axis: enteroendocrine signals (e.g., PYY and ghrelin) and neural pathways that link the gut with appetite regulation, adipose tissue, and systemic metabolism; (3) Gut–Liver Axis: the role of microbiota-modified bile acids (FXR/TGR5 pathways) and bacterial endotoxins in non-alcoholic fatty liver disease (NAFLD) and hepatic insulin resistance; (4) Gut–Kidney Axis: how gut-derived toxins and nutrient handling intersect with diabetic kidney disease and how incretin-based and SGLT2 inhibitor therapies leverage gut–kidney communication. Shared mechanisms (microbial SCFAs improving insulin sensitivity, LPS driving inflammation via TLR4, and aryl hydrocarbon receptor ligands modulating immunity) are synthesized into a unified model. An integrated understanding of Gut-X axes reveals new opportunities for treating and preventing T2D. Modulating the gut microbiome and its metabolites (through diet, pharmaceuticals, or microbiota therapies) can improve glycemic control and ameliorate complications by simultaneously influencing pancreatic islet function, hepatic metabolism, and systemic inflammation. However, translating these insights into clinical practice requires addressing gaps with robust human studies. This review provides a state-of-the-art synthesis for researchers and clinicians, underlining the gut as a nexus for multi-organ metabolic regulation in T2D and a fertile target for next-generation therapies. Full article

Despite their crucial biological role as metabolites, reactive oxygen and reactive nitrogen species (ROS and RNS) can have a negative effect on organisms when their cellular contents overwhelm the normal equilibrium provided by antioxidant defenses. Important biomolecules, such as lipids, proteins, and nucleic acids (i.e., DNA), can be damaged by their oxidative effects, resulting in malfunction or a shorter lifespan of cells and, eventually, of the whole organism. Oxidative stress can be defined as the consequence of an imbalance of pro-oxidants and antioxidants due to external stress sources (e.g., exposure to xenobiotics, UV radiation, or thermic stress). It can be evaluated by monitoring specific biomarkers to determine the state of health of breathing organisms. Assessments of ROS, RNS, specific degenerative oxidative reaction products, and antioxidant system efficiency (antioxidant enzyme activities and antioxidant compound contents) have been extensively performed for this purpose. A wide variety of analytical methods for measuring these biomarkers exist in the literature; most of these methods involve indirect determination via spectrophotometric and spectrofluorometric techniques. This review reports a collection of studies from the last decade regarding contaminant-induced oxidative stress in insects, with a brief description of the analytical methods utilized. Full article

Volatile organic compounds (VOCs) are common indoor air pollutants known to pose significant health risks, yet little is known about how internal exposure varies across populations and environments. This study investigated the associations between indoor air pollutants and urinary VOC biomarkers in a nationally representative sample. We analyzed data from 1880 adults in the eighth Korea National Health and Nutrition Examination Survey (2020–2021) who completed an indoor air quality (IAQ) survey and provided urine samples, assessing the influence of sociodemographic, behavioral, and environmental factors. Indoor concentrations of PM_2.5, CO₂, formaldehyde, total VOCs, benzene, ethylbenzene, toluene, xylene, and styrene were measured, alongside the urinary concentrations of nine VOC biomarkers. Associations between pollutants, sociodemographic variables, and biomarkers were evaluated using univariate and multivariable linear regression with Bonferroni correction. Older age, female, lower socioeconomic status (SES), and smoking were associated with higher urinary VOC biomarker concentrations, with smoking showing the strongest associations. Indoor ethylbenzene, styrene, benzene, and CO₂ were also associated with multiple metabolites. These findings indicated significant associations between household air pollutants and urinary VOC metabolites, with disparities by age, sex, SES, and smoking status, underscoring the importance of targeted IAQ interventions for vulnerable populations. Full article

Myxobacteria, a group of swarming, predatory soil bacteria, are of interest because of their biocontrol potential. In this study, the inhibitory effects of 13 strains of myxobacteria were examined against four different phytopathogenic fungi, as follows: two isolates of Rhizoctonia solani from different AG groups and one isolate each from Sclerotinia sclerotiorum and the oomycete Pythium ultimum. Inhibition levels varied among phytopathogens, with slow-growers being more susceptible than fast-growers. Myxococcus xanthus BS 248, M. flavus ATCC 29617, and M. coralloides BS249 were the most inhibitory strains tested. non-contact and contact inhibition on agar media between phytopathogens and myxobacteria were visually discernible. This distinction potentially reflects the activity of low-molecular-weight metabolites and high-molecular-weight lytic enzymes, respectively. In a pot soil study, the inhibitory effect of a mixture of two strains of myxobacteria against two strains of R. solani was apparent from the reduced disease in cucumber seedlings compared to controls without myxobacteria. This is the first report of an in vivo inhibitory effect of myxobacteria against Rhizoctonia. The survival of M. xanthus BS248 in sterile soil amended with rabbit manure (1:1) increased up to five weeks compared to one week in soil without the manure, suggesting that organic amendment could enrich myxobacteria in soil. Full article

Improving the efficacy of microbial biocontrol agents is a pivotal strategy for sustainable management of rice blast and sheath blight caused by Pyricularia oryzae and Rhizoctonia solani, respectively, in Vietnam. In this study, Trichoderma sp. TVN-A0 and Trichoderma sp. TVN-H0 were irradiated by gamma to generate mutants for screening the enhanced antagonistic activity against P. oryzae and R. solani. The potential mutants were screened by antifungal metabolite production via the cellophane membrane assay (I_CM), antagonistic performance through dual culture confrontation assays (I_DC), volatile organic compound bioassays (I_VOCs), and chitinase activity. As a result, among five potential mutants derived from each wild-type strain (AM1-AM5 and HM1-HM5), mutant AM2 originated from TVN-A0, and mutant HM2 derived from TVN-H0 demonstrated the highest inhibition rates and chitinase activities. The AM2 exhibited I_CM of 96.71% against R. solani, 92.57% against P. oryzae, I_DC of 87.76%, and I_VOCs of 83.57%, while HM2 possessed I_CM of 95.33% against R. solani, 85.28% against P. oryzae, I_DC of 91.24%, and I_VOCs of 79.33%. The genetic differences among mutants and their parents were investigated by RAPD. The non-GMO AM2 and HM2 mutants are promising candidates for biocontrol of the diseases caused by P. oryzae and R. solani in Vietnam. Full article

Secondary metabolites derived from plants, such as flavonoids, alkaloids, and terpenoids, are being increasingly utilized because of their bioactivity and ubiquitous distribution. Although their pharmacological uses and agricultural applications are well studied, their potential role as endocrine-disrupting compounds (EDCs) in non-target environmental organisms is largely unknown. This review aims to update our knowledge on the endocrine-disrupting effects induced by plant-derived metabolites in environmental testing models. We review guidelines and conceptual models for standardized testing approaches used to assess endocrine disruption and identify critical data gaps in the context of mammalian test systems compared to those for environmental species. We also emphasize the known endocrine mechanisms, including the regulation of estrogen and thyroid pathways and their effects on reproduction and hormonal regulation in environmental species. By integrating evidence across diverse biological systems, this work intends to provide a link between toxicological and ecological perspectives on the emerging role of plant-derived metabolites as potential EDCs in natural ecosystems. Importantly, we highlight that an extensive assessment of plant-derived metabolites is required to improve understanding of their ecological hazards and the mechanisms of their effects. Full article

Per- and polyfluoroalkyl substances (PFASs) are widespread in the environment, bioaccumulate in humans, and lead to disease and organ injury, such as liver steatosis. However, we lack a clear understanding of how these chemicals cause organ-level toxicity. Here, we aimed to analyze PFAS-induced metabolic perturbations in male and female rat livers by combining a genome-scale metabolic model (GEM) and toxicogenomics. The combined approach overcomes the limitations of the individual methods by taking into account the interaction between multiple genes for metabolic reactions and using gene expression to constrain the predicted mechanistic possibilities. We obtained transcriptomic data from an acute exposure study, where male and female rats received a daily PFAS dose for five consecutive days, followed by liver transcriptome measurement. We integrated the transcriptome expression data with a rat GEM to computationally predict the metabolic activity in each rat’s liver, compare it between the control and PFAS-exposed rats, and predict the benchmark dose (BMD) at which each chemical induced metabolic changes. Overall, our results suggest that PFAS-induced metabolic changes occurred primarily within the lipid and amino acid pathways and were similar between the sexes but varied in the extent of change per dose based on sex and PFAS type. Specifically, we identified that PFASs affect fatty acid-related pathways (biosynthesis, oxidation, and sphingolipid metabolism), energy metabolism, protein metabolism, and inflammatory and inositol metabolite pools, which have been associated with fatty liver and/or insulin resistance. Based on these results, we hypothesize that PFAS exposure induces changes in liver metabolism and makes the organ sensitive to metabolic diseases in both sexes. Furthermore, we conclude that male rats are more sensitive to PFAS-induced metabolic aberrations in the liver than female rats. This combined approach using GEM-based predictions and BMD analysis can help develop mechanistic hypotheses regarding how toxicant exposure leads to metabolic disruptions and how these effects may differ between the sexes, thereby assisting in the metabolic risk assessment of toxicants. Full article

Background: This study investigates metabolic perturbations in serum samples associated with different genotypes (AA, AC, and CC) of the schizophrenia susceptibility gene NOS1AP-rs12742393. Methods: Publicly available datasets acquired using ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC–QTOFMS) were analyzed by employing network and enrichment approaches. Results: Key metabolites, including tryptophan, 2-aminobutyric acid, palmitic acid, and 5-hydroxytryptophan, were strongly linked to metabolic networks in genotypes AA-AC and AA. Enrichment analysis was conducted to identify metabolite sets differentially distributed across these genotypes, with a particular focus on genotype AA. Conclusions: The findings suggest that NOS1AP-rs12742393 contributes to complex metabolic alterations involving amino acids, organic compounds, fatty acids, and cholic acids. Moreover, serum metabolome analysis demonstrates sufficient sensitivity and specificity to provide insights into NOS1AP-rs12742393 genotype-associated metabolic profiles, supporting a network-based approach to understanding schizophrenia susceptibility. Full article

Background: The bacterial wilt of tomatoes, caused by Ralstonia solanacearum, is a soil-borne plant disease that causes substantial agricultural economic losses. Various nanoparticles have been utilized as antibacterial agents to mitigate pathogenic destructiveness and improve crop yields. However, there is a lack of in-depth research on how nanoparticles affect tomato metabolite levels to regulate the bacterial wilt of tomatoes. Methods: In this study, healthy and bacterial wilt-infected tomatoes were treated with Cu-Ag nanoparticles, and a metabolomics analysis was carried out. Results: The results showed that Cu-Ag nanoparticles had a significant prevention and control effect on the bacterial wilt of tomatoes. Metabolomic analysis revealed that the nanoparticles could significantly up-regulate the expression levels of terpenol lipids, organic acids, and organic oxygen compounds in diseased tomatoes, and enhance key metabolic pathways such as amino acid metabolism, carbohydrate metabolism, secondary metabolite metabolism, and lipid metabolism. These identified metabolites and pathways could regulate plant growth and defense against pathogens. Correlation analysis between the tomato microbiome and metabolites showed that most endophytic microorganisms and rhizospheric bacteria were positively correlated with fatty acyls groups and organic oxygen compounds. Conclusions: This study reveals that Cu-Ag nanoparticles can actively regulate the bacterial wilt of tomatoes by up-regulating the levels of lipid metabolism and organic oxygen compounds, providing an important theoretical basis for the application of nanoparticles in agriculture. Full article