Search Results (282)

Microbial contamination in hospitality settings remains understudied despite the high density of human contact and diverse operational activities that characterize hotel environments. This study aimed to characterize microbial contamination patterns and environmental hygiene risks across multiple functional areas of family-oriented hotels. A cross-sectional environmental microbiological investigation was conducted in family hotels in Bavaria, Germany. A total of 225 environmental surface samples were collected from guest rooms, child areas, food-related areas, service environments, and water-exposed locations. Bacterial isolates were identified using culture-based microbiology and MALDI-TOF mass spectrometry. Microbial prevalence, contamination severity, microbial richness, and pathogen prevalence were assessed using mixed-effects ordinal logistic regression, generalized additive model (GAM), and integrated hygiene profile, all performed in R (version 4.5.1). Microbial occurrence patterns differed markedly across functional areas. Contamination category distributions differed significantly among areas, with food-related environments showing the strongest enrichment in the highest contamination category (72.7%). Food-related areas showed significantly greater odds of severe contamination than guest rooms (OR = 8.37, 95% CI: 1.89–37.00), child areas (OR = 6.16, 95% CI: 1.20–31.46), and water-exposed environments (OR = 12.34, 95% CI: 2.45–62.10). Microbial richness differed across operational zones (p = 0.048) and was positively associated with contamination severity (β = 0.141, p < 0.001). GAM revealed a significant non-linear richness–contamination relationship (p < 0.001). Integrated hygiene profile consistently identified food-related and service areas as the highest risk environments. Environmental hygiene risks in hospitality settings display functional-area heterogeneity, highlighting the need for targeted, area-specific hygiene management strategies. Full article

Bacterial diseases remain a significant threat to salmonid aquaculture worldwide, especially in semi-open cage culture systems that are exposed daily to natural aquatic environments. This study investigates recurring bacterial disease events in Rainbow Trout (Oncorhynchus mykiss) raised in a semi-open cage culture facility in the Bicaz mountain reservoir in Romania. Longitudinal monitoring was conducted through clinical assessment of fish health, post-mortem examination of fish that died during recurrent mortality events, bacterial isolation followed by MALDI-TOF MS identification, and determination of antimicrobial susceptibility profiles of the isolated bacteria from 2023 to 2026. These investigations demonstrated the presence of classical pathogenic bacteria found in salmonids as well as a diverse range of opportunistic environmental bacteria. Recurrently identified bacteria included Aeromonas hydrophila, Yersinia ruckeri, Aeromonas salmonicida, Aeromonas veronii, Pseudomonas fluorescens, Hafnia alvei, Enterobacter aerogenes, Providencia alcalifaciens, and Flavobacterium psychrophilum. Mixed bacterial infection resulted in several of the bacterial disease outbreaks, indicating that there are likely to be complex microbial relationships within this semi-open aquaculture environment. Susceptibility profiles of antibiotics tested against the isolated bacteria indicated that some antibiotic classes had varying degrees of susceptibility between different bacterial disease outbreaks and also varied between susceptible and resistant strains of the same bacterial species. Susceptibility profiles were most commonly noted for florfenicol and fluoroquinolone, while beta-lactams, macrolides, and lincosamides displayed variable levels of resistance or diminished susceptibility patterns, particularly among Aeromonas spp. strains. Therefore, the results highlight the dynamic epidemiological characteristics of bacterial infections occurring in semi-open mountain aquaculture systems and underscores the importance of longitudinal bacteriological surveillance under commercial farming conditions. Permanent interaction between cultured fish and the aquatic microbiota may influence the recurrence and microbial complexity of bacterial outbreaks in reservoir-based salmonid aquaculture. Full article

Background: Obesity and mental disorders are associated with gut microbiota dysbiosis and gut–brain axis dysfunction. This secondary analysis evaluated the effects of a 12-week weight loss program (WLP) based on a hypocaloric traditional Mexican diet (TMD) and moderate-intensity exercise on gut microbiota, body composition (BC), and metabolic parameters in Mexican adults with obesity with and without depression and anxiety symptoms. Methods: A total of 106 adults with obesity were classified based on the presence or absence of depressive and anxiety symptoms into an obesity control group without symptoms (OCG), improved symptoms (OIS), and persistent symptoms (OPS). Stool samples were analyzed by sequencing the V3–V4 region of the 16S rRNA gene. Longitudinal changes in serum biochemistry, BC, intestinal permeability markers, and gut microbiota were analyzed using linear mixed-effects models. Differential taxa were identified using linear discriminant analysis effect size (LEfSe), and associations between bacterial genera, biochemical variables, and dietary components were explored using MaAsLin 2. Results: The WLP significantly improved metabolic, inflammatory, intestinal permeability, and BC markers, as well as depressive and anxiety symptoms, although participants remained in WHO grade I obesity. These improvements were accompanied by selective, group-dependent modulation of bacterial genera rather than broad microbiota restructuring. LEfSe identified 22 taxonomic biomarkers: 16 in OPS, 5 in OIS, and 1 in OCG. Conclusions: The culturally adapted WLP, which combined a hypocaloric TMD with exercise, promoted improvements in metabolism and BC in all participants, along with group-specific gut microbiota remodeling that may be associated with differential changes in depressive and anxiety symptoms in the context of persistent obesity. Full article

Background: Public fitness facilities are high-contact environments that facilitate microbial transfer via shared surfaces; however, temporal dynamics and device-specific contamination patterns remain insufficiently characterized. Methods: A repeated-measures observational study was conducted in a fitness facility over five consecutive weekdays (Monday to Friday). A total of 180 surface samples were collected from 12 gym devices, each sampled three times daily (morning, noon, and evening). Surface-associated cultivable bacteria were recovered using culture-based methods followed by MALDI-TOF MS identification. Ecological metrics, including species richness and Shannon diversity, were calculated, and taxa were classified by origin (skin-associated versus environmental). Device-specific contamination profiles were developed using a composite index incorporating pathogen presence, contamination frequency, and persistence. Temporal trends and predictors of contamination were analyzed using mixed-effects regression models. All statistical analyses were performed in R. Results: A total of 248 bacterial isolates were identified, representing 61 species across 32 families, with a predominance of skin-associated taxa (72.2%). Sampling time point was a strong independent predictor of contamination (adjusted OR for noon vs. morning: 7.19; p < 0.001). While overall microbial diversity remained stable across devices (Shannon index, p = 0.44), substantial heterogeneity was observed in pathogen prevalence, multispecies burden, and persistence. The functional trainer and leg extension showed the highest composite risk scores (42.3%), while the ab crunch machine and upper body ergometer demonstrated significantly increasing contamination trends over the sampling period (p < 0.05). Co-occurrence analysis showed nonrandom microbial associations, with the strongest positive links between Micrococcus luteus and Staphylococcus saprophyticus (Φ = 0.76) and Staphylococcus aureus (Φ = 0.61). Conclusions: Gym equipment surfaces harbor predominantly human-associated microbial communities exhibiting dynamic temporal contamination patterns, and on selected devices, increasing the baseline contamination across consecutive cleaning cycles. The findings indicate that contamination patterns on shared fitness equipment are dominated by taxa commonly associated with human skin and support targeted hygiene interventions focused on frequently contacted devices and periods of elevated contamination. Full article

Background: Atopic dermatitis is a chronic inflammatory skin disease in children, frequently associated with skin barrier dysfunction, immune dysregulation, and dysbiosis. Infected, treatment-resistant lesions may increase disease severity and complicate management, particularly in the presence of Staphylococcus aureus colonization. Objectives: To characterize the microbiological profile of infected, non-responsive pediatric atopic dermatitis, evaluate short-term clinical outcomes following individualized treatment, and identify predictors of disease severity. Methods: This observational analytical study included 41 children with atopic dermatitis recruited at Saint Constantin Hospital, Brașov, Romania, between September 2025 and February 2026. Eligible patients fulfilled the Hanifin and Rajka criteria and presented with infected, treatment-resistant lesions. Skin cultures were subjected to an antibiogram and antifungigram. Disease severity was assessed using the Patient-Oriented Eczema Measure (POEM) and SCORAD at baseline, 7 days, and 30 days. Repeated-measures ANOVA, mixed ANOVA, and hierarchical linear regression were used for statistical analysis. Results: Staphylococcus aureus was the predominant pathogen, followed by other bacterial species. Both POEM and SCORAD scores improved significantly over the 30-day follow-up, with marked improvement after 7 days and further reduction by day 30. Although patients with S. aureus colonization and those receiving systemic therapy tended to have higher disease severity, neither factor significantly influenced the trajectory of clinical improvement. Baseline disease severity was the strongest predictor of 30-day POEM and SCORAD outcomes, whereas demographic and perinatal characteristics did not independently predict short-term clinical outcomes. Conclusions: Individualized management was associated with significant improvements in clinician-assessed disease severity and patient-reported symptoms during the 30-day follow-up. Staphylococcus aureus, particularly methicillin-sensitive S. aureus (MSSA), was the most frequently isolated pathogen. Baseline disease severity was the strongest predictor of short-term clinical outcomes, whereas the evaluated demographic and perinatal characteristics did not provide additional predictive value in this cohort. Larger prospective controlled studies are needed to confirm these findings. Full article

Background/Objectives: Abnormal vaginal discharge (AVD) is a common complaint among women of reproductive age, often involving multiple, overlapping etiologies, most commonly bacterial vaginosis (BV), vulvovaginal candidiasis (VVC), aerobic vaginitis (AV), and sexually transmitted infections (STIs). We aimed to evaluate a syndromic diagnostic approach by developing qPCR-derived dysbiosis indices for BV, VVC, and AV, subsequently comparing their performance against established reference methods and clinician-assigned diagnoses. Methods: Vaginal swabs were collected in a case–control design from 74 symptomatic and 64 asymptomatic women at two clinics in Slovenia. Commercial qPCR assays quantified the microbial species associated with AVD. Relative abundances were integrated into novel dysbiosis indices. Diagnostic performance was validated against the Nugent scoring system (for BV), semiquantitative Candida culture with clinical symptoms (for VVC), and Hay–Ison criteria (for AV). Results: In this internally validated study, dysbiosis indices demonstrated high agreement with their respective reference tests and outperformed clinician-assigned diagnoses across all three conditions. The syndromic approach further revealed that mixed etiologies were frequent, leading to a diagnostic resolution for this patient subset. Conclusions: qPCR-based microbial dysbiosis indices offer a robust alternative to microscopy, particularly in settings where microscopy is not routinely performed. This method improves the accuracy of AVD evaluation and supports more targeted clinical management. Full article

Background/Objectives: Bacterial contamination of the surgical field during shoulder arthroplasty may contribute to periprosthetic joint infection (PJI), yet data on intraoperative bacterial load and its clinical correlates remain limited. This study aimed to evaluate culture positivity and bacterial load in specimens collected at the end of reverse total shoulder arthroplasty (RTSA) and to explore their association with patient-related factors. Methods: Fifty-five patients undergoing elective RTSA were consecutively enrolled. At the end of surgery, three specimens per patient (two prosthetic swabs and one periprosthetic tissue sample) were collected for qualitative and quantitative microbiological analysis. Associations between bacterial load and clinical variables were assessed using mixed-effects linear regression models, while time to culture positivity was analysed using mixed-effects Cox regression models. Results: Among 165 specimens, Cutibacterium acnes was isolated in 42.4% and coagulase-negative staphylococci in 29.1%. C. acnes showed significantly higher bacterial loads (1.38 × 10³ CFU/mL) compared with aerobic bacteria (6.54 × 10¹ CFU/mL). Higher C. acnes load was associated with male sex, older age, higher body mass index, smoking, and cuff tear arthropathy, whereas massive rotator cuff tear and longer time to positivity were inversely associated. Aerobic bacterial load was primarily associated with longer surgical duration. Time to positivity was shorter for aerobes than for C. acnes. Conclusions: Intraoperative bacterial contamination during RTSA is frequent and characterized by marked differences in bacterial load and growth kinetics. Quantitative assessment of bacterial burden may improve the interpretation of unexpected positive cultures. Full article

Automated AI-assisted colony counting may improve standardization in digital microbiology, but performance can be affected by colony density, culture medium, colony morphology, adhesion, and plate artifacts. We evaluated the Starry-300 AI colony counting system using 382 standardized pure culture bacterial and yeast plates across four agar media. AI-assisted counts were compared with a three-reader median ImageJ-assisted manual comparator derived from independent counts by experienced technologists. The AI workflow showed close agreement with the manual consensus comparator across a broad colony density range. Overall, 360/382 plates (94.24%) were within ±10 CFU and 377/382 plates (98.69%) were within ±30 CFU of the manual median count. Error-based and agreement analyses showed a mean absolute error of 3.19 CFU/plate; both the intraclass correlation coefficient and Lin’s concordance correlation coefficient were0.99. AI software analysis required approximately 5–15 s/plate, although this did not include plate handling, correction, or reporting. These findings support the analytical feasibility of reviewable AI-assisted colony enumeration under controlled pure culture conditions. Further validation using primary clinical specimens, mixed cultures, near-threshold samples, and external sites is required before broad clinical implementation. Full article

This research presents bacterial cellulose (BC) filaments knitted from agro-industrial by-products. The fermentation media came from pressed fruit (beetroot, ginger, grape), vegetable beverages, bagasse with different concentrations (1/2.5, 1/5, 1/7.5, and 1/10), and a control medium with unrefined sugar from sugarcane or panela. The BC filaments were obtained from a mixed culture of bacteria and yeast (SCOBY); functionalized using NaOH purification treatment and glycerol plasticizer; untwisted and twisted with 1-, 2-, and 4-ply; and characterized physically and mechanically by weight, diameter, tensile strength, Young’s modulus, and elongation. The untwisted and 2-ply twisted BC filaments from the fruit medium 1/2.5 showed tensile strength of 272 MPa and 155 MPa, respectively. Finally, control panela filaments with 1-, 2-, and 4-ply and fruit filaments with 2- and 4-ply were knitted in wet states. This research demonstrates the use of by-products to produce BC filaments with knitting properties for textile applications. Full article

Background/Objectives: Parabens are widely used preservatives detected at trace levels in drinking water. Although their endocrine-disrupting effects are well established, their long-term impact on environmental bacteria remains poorly understood. This study investigated the effects of parabens on changes in bacterial phenotypic virulence traits and antimicrobial tolerance of bacteria within drinking water biofilms. Methods: Acinetobacter calcoaceticus and Stenotrophomonas maltophilia biofilms were grown on polyvinyl chloride coupons for 26 days under exposure to methyl- (MP), propyl- (PP), butyl-paraben (BP), or a paraben mixture (MIX) at 0.15 µg/L. Biofilm regrowth and virulence-associated traits, including motility (swimming, swarming, and twitching), extracellular enzymes (gelatinase, protease, and lipase), and siderophore production, were evaluated. The effect of prolonged MP exposure (10 weeks) on antimicrobial tolerance was assessed. Results: In A. calcoaceticus, MP reduced biofilm biomass by 32%, whereas MIX increased biomass by 25% and culturability (1.1-fold). S. maltophilia showed increased biofilm culturability with PP (50%), and increased biomass of 2.6-, 2.4-, and 1.8-fold for PP, BP, and MIX, respectively. Biofilm cells exhibited higher virulence factor production than planktonic counterparts. S. maltophilia biofilm cells exposed to BP and MIX showed enhanced swimming and swarming motility, with halo diameters up to fivefold larger than controls. Lipase production increased under BP and MIX exposure, whereas MP exposure reduced it. A MP-induced reduction in motility was observed for A. calcoaceticus and S. maltophilia. Long-term MP exposure results in reduced susceptibility to ceftazidime and minocycline in A. calcoaceticus. Conclusions: Environmentally relevant concentrations of parabens can modulate bacterial virulence traits, increasing biofilm formation, motility and lipase production, and antimicrobial tolerance. Full article

Demographic growth and the global environmental crisis have intensified the need to reconcile energy generation with the protection of terrestrial ecosystems. Traditional organic waste management systems are inefficient in handling high pollutant loads, leading to uncontrolled methane emissions and degradation of soil and water. In response to this challenge, the present study aimed to conduct a critical review of how Microbial Fuel Cells (MFCs) valorize biomass to align climate action (SDG 13) with the protection of terrestrial life (SDG 15). Through a bibliometric analysis of the Scopus database (2010–2026), supported by tools such as Bibliometrix, 460 documents were examined, complemented by a systematic literature review addressing biomass types, microbial interactions, and electrode modifications. The main findings indicate that MFC research is currently in an exponential growth phase (R² = 0.99954), with Environmental Sciences (23%) and Chemical Engineering (15%) as the predominant fields. Industrial and plant residues exhibit the highest bioelectric potential, while mixed microbial consortia—particularly fungal–bacterial synergies—outperform pure cultures in degradative efficiency and energy generation, reaching up to 1760 mW/m² with Geobacter sulfurreducens bioaugmentation. Electrode modification with nanomaterials such as NiO or MWCNTs substantially enhances charge transfer. Standardization of measurement protocols, ecological impact assessment of nanomaterials, and evaluation of the economic–environmental feasibility of MFC-integrated biorefineries are recommended to ensure scalability and effective contributions to SDGs 13 and 15. Full article

Enterococcus cecorum has been identified as causing early sepsis in commercial broilers. We hypothesized that vertical transmission may contribute to the spread of the pathogen. Sampling of 360 commercial broiler eggs from a previously infected flock detected Enterococcus gallinarum and Enterococcus faecalis in yolks of 18-day incubated eggs. Enterococcus avium was recovered by enrichment from 1 of 31 unincubated yolks. Direct sampling without enrichment of 297 egg yolks from a previously infected broiler breeder flock detected E. faecalis, Escherichia coli, Globicatella sanguinis, and E. gallinarum, often in high numbers, or in coinfections. Microbiological sampling of day-of-hatch chicks suggested only the yolk sac was likely to yield bacterial growth, and that yolks could be sampled directly using swabs streaked onto growth medium. The most common isolate from sampling 30 day-of-hatch broiler chicks was E. faecalis from 16 different chicks. Further, E. coli was recovered as a mixed infection with E. faecalis in 3 of those 16 residual yolk sacs. From swab-sampling of residual yolk sacs from 40 day-of-hatch broiler breeder chicks, E. faecalis was recovered from 7 chicks. Thus, yolk infections by Enterococcus species were the primary isolates cultured from commercial broilers and broiler breeders in Arkansas. Identification of these species at high numbers in yolks is likely contributing to reduced hatchability, early chick death, and transmission of bacteria to subsequent flocks. Therefore, the broiler industry needs to pursue methods to identify infected laying hens and management strategies to mitigate vertical transmission. Importance: We were unable to identify E. cecorum being spread from flock to flock via vertical transmission. We did identify specific bacterial species infecting and reproducing within the yolks of developing embryos and day-old chicks of commercial, meat-type chickens. These particular species were detected at low and high levels, indicating growth within the yolk. The implication is that these species colonized the yolk within the hen’s reproductive tract and were vertically transmitted to the chicks and subsequent flocks. Some infections represent only a single species, while others involve two species that may represent cooperative infections. With the removal of the use of antibiotic growth promoters during early development, these species may be reducing chicken reproduction through embryo death or early chick mortality. Full article

Yeasts are among the intrinsic factors affecting the quality of beer due to their impact on flavor. Apart from a long and rich brewing tradition of natural fermentations, involving different yeast and bacterial species in regions such as Belgium, non-Saccharomyces yeasts have not been the preferred industrial inoculation strains in both winemaking and brewing sectors. This is mainly due to their slower fermentation rates, lower alcohol tolerance, and limited ability to complete fermentation. This review explores the brewing characteristics of Torulaspora delbrueckii strains, focusing on the aromatic profile of the produced beers, in comparison with the well-known Saccharomyces cerevisiae brewing strains. The effect of fermentation parameters, as well as the use of mono- and mixed cultures with S. cerevisiae, is discussed. Specific T. delbrueckii strains have demonstrated the ability to ferment wort sugars and produce alcohol levels of up to 4–6% (v/v). The main volatile compounds produced include higher alcohols, such as isoamyl and phenyl ethyl alcohol, as well as esters and their acid precursors. Among these, ethyl hexanoate and ethyl octanoate are particularly important due to their contribution to fruity aromas. Mixed fermentations involving T. delbrueckii and S. cerevisiae have been shown to enhance ester production, resulting in improved aromatic complexity in the final product. Full article

Brucellosis remains a significant zoonotic disease globally, causing considerable economic and public health consequences, particularly in high-risk areas of South Africa (SA) with extensive animal production, including the Limpopo and Free State provinces. This study used a combination of serological, microbiological, and molecular assays to investigate the prevalence and characteristics of Brucella in 580 slaughtered livestock (384 cattle and 196 sheep) in Limpopo and the Free State (192 cattle and 98 sheep in each province) and to compare the diagnostic findings obtained using these assays. Tissue samples collected from each animal included liver, lung, spleen, and lymph nodes. Using the standard diagnostic rose Bengal test (RBT) and complement fixation test (CFT) in series (RBT-CFT), only 2.6% (10/384) of cattle were positive, with 2.1% (95% CI: 0.7–4.9) and 3.1% (95% CI: 1.3–6.3) in the Free State and Limpopo, respectively, while 4.7% (18/384) were positive by RBT-indirect enzyme-linked immunosorbent assay (iELISA), with 5.2% (95% CI: 2.7–9.0) and 4.2% (95% CI: 2.0–7.7) in the Free State and Limpopo, respectively. The molecular prevalence was 18.5% for Brucella deoxyribonucleic acid (DNA), while 97% of PCR-positive cattle tested seronegative in both provinces. Ovine samples were largely seronegative despite showing higher polymerase chain reaction (PCR) positivity (28.6%). Brucella abortus predominated in both species, with B. melitensis and occasional mixed infections also detected. Mixed infections in this study were defined as samples producing multiple species-specific bands within the same sample, consistent with the presence of more than one Brucella species during multiplex PCR analysis. While liver and spleen tissue provided reliable PCR detection, bacterial culture yielded a 0% isolation rate. These findings, together with reports from studies in brucellosis-endemic areas in sub-Saharan Africa, demonstrate discrepancies between traditional serological methods and molecular methods, including detection of Brucella DNA in seronegative animals. This may indicate that some infected animals (chronic or latent carriers) are not identified by conventional serological assays alone, particularly in endemic settings. To strengthen surveillance and enhance the detection of exposed animals, the incorporation of iELISA as a complementary tool into South Africa’s routine surveillance programmes may be beneficial, particularly when combined with regular testing of all animals. Full article

Issatchenkia orientalis Y1 is an important functional microorganism during the fermentation of strong-flavor Baijiu and may influence microbial community structure, community assembly mechanisms, and microbial functional potential predicted from sequencing data. In this study, a mixed-culture fermentation system was established using fermented grains and Huangshui from strong-flavor Baijiu production. I. orientalis Y1, isolated from fermented grains, was inoculated into this system as a perturbation treatment to investigate its effects on microbial diversity, community composition, and functional profiles, as well as its influence on microbial community assembly pathways. The results showed that inoculation with I. orientalis Y1 significantly altered microbial diversity and increased community complexity. The relative abundances of Paenibacillus, Aspergillus, and Acetobacter decreased, with the peak abundance of Paenibacillus declining from 62.8% to 40.2% and that of Acetobacter decreasing from 27.8% to 19.1%, while Aspergillus remained consistently less abundant than in the control group throughout fermentation. In contrast, the relative abundances of Issatchenkia and Lactobacillus increased, with their peak abundances rising from 15.0% to 23.9% and from 7.6% to 27.0%, respectively. In addition, it increased the contribution of deterministic processes in community assembly, with the deterministic proportion rising from 31.1% to 35.5% in bacterial communities and from 28.4% to 48.8% in fungal communities, while the contribution of stochastic processes decreased. These changes suggest that the microbial community became more controllable and functionally more stable after inoculation. Meanwhile, the overall predicted metabolic activity of the microbial community declined. In conclusion, the addition of I. orientalis Y1 reshaped microbial community structure, influenced microbial community assembly processes, and altered the correlations between dominant microorganisms and metabolic pathways. Full article