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Purpose: To investigate the antimicrobial effects of a mouthrinse containing silver nanoparticles (AgNP) on polymicrobial biofilms in vitro., Materials and Methods: Polymicrobial biofilms were grown on glass cover slips following the method of Exterkate. Saliva collected from a healthy human was added to McBain medium (including 0.2% sucrose) to achieve a 50-fold dilution. Glass coverslips were attached to the lid of a 24-well culture plate and suspended in the medium of each well. After 24 h of cultivating, coverslips with biofilms were immersed in each of four treatment solutions or sterile deionized water for 5 min. The control and four treatment groups were as follows: 1) control: sterile deionized water; 2) nanosilver (NS): mouthrinse containing AgNP; 3) 0.05C: 0.05% chlorhexidine gluconate; 4) 0.2C: 0.2% chlorhexidine gluconate; 5) Xyl: 25% xylitol. The biofilms were further regrown for 48 h. After removing the biofilms ultrasonically, they were cultured on blood agar, viable cells were counted, and the amount of lactic acid in the biofilms was analysed using a colorimetric assay., Results: Mouthrinse containing AgNP suppressed viable cells in the biofilm to the same degree or more than with chlorhexidine gluconate. Amounts of lactic acid after 72 h cultivation of biofilms treated with 0.2C and NS showed consistently low values., Conclusion: The mouthrinse containing AgNP suppressed viable cells in polymicrobial biofilms to the same level as 0.2% chlorhexidine or higher.

Objective: The human gut microbiota is composed of many viruses, bacteria, and fungi. Escherichia coli representatives are facultative anaerobic bacteria in the colon that play a crucial role in the metabolism of lactose, vitamin synthesis, and immune system modulation. E. coli forms a biofilm on the epithelial cell surface of the intestine that can be modified by diet compounds, i.e., gluten, xylitol, lactose, and probiotics., Methods: In the present study, the impact of probiotic-derived Lactobacillus rhamnosus GG strain on non-pathogenic E. coli biofilm was examined. The mono- and multispecies biofilm was also treated with gluten, xylitol, and lactose. We used 96-well plates to obtain biofilm growth. Biofilm was stained using crystal violet. To evaluate the type of interaction in mono- and multispecies biofilm, a new formula was introduced: biofilm interaction ratio index (BIRI). To describe the impact of nutrients on biofilm formation, the biofilm formation impact ratio (BFIR) was calculated., Results: The biofilms formed by both examined species are stronger than in monocultures. All the BIRI values were above 3.0. It was found that the monospecies biofilm of L. rhamnosus is strongly inhibited by gluten (84.5%) and the monospecies biofilm of E. coli by xylitol (85.5%). The mixed biofilm is inhibited by lactose (78.8%) and gluten (90.6%)., Conclusion: The relations between bacteria in the mixed biofilm led to changes in biofilm formation by E. coli and L. rhamnosus GG. Probiotics might be helpful in rebuilding the gut microbiota after broad spectrum antibiotic therapy, but only if gluten and lactose are excluded from diet., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Biofilms formed by Pseudomonas aeruginosa and Staphylococcus aureus, along with their antibiotic tolerance have posed challenges to treatment strategies for lung, wound, and other infections, particularly when co-infecting. In the present study, the inhibitory effect of xylitol on biofilm formation, as well as its eradication potential on pre-established biofilms formed by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and a mix of both species in an alginate bead model were tested. Xylitol concentrations of 2, 1, and 0.5 M reduced biofilm formation by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and the mixed-species biofilm in a concentration-dependent manner. Additionally, biofilms formed by these species were subjected to treatment with xylitol. Xylitol was also capable of eradicating biofilms established by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and the mixed-species biofilm by at least 20%, with the most effective eradication observed for P. aeruginosa strain PAO1. The present study indicates the effectiveness of xylitol as both an inhibitory and eradicating agent against biofilms formed by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and a mix of both species in an alginate bead model, which mimics the in vivo characteristics of P. aeruginosa aggregates., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and Aims: The pathways and metabolites that contribute to residual cardiovascular disease risks are unclear. Low-calorie sweeteners are widely used sugar substitutes in processed foods with presumed health benefits. Many low-calorie sweeteners are sugar alcohols that also are produced endogenously, albeit at levels over 1000-fold lower than observed following consumption as a sugar substitute., Methods: Untargeted metabolomics studies were performed on overnight fasting plasma samples in a discovery cohort (n = 1157) of sequential stable subjects undergoing elective diagnostic cardiac evaluations; subsequent stable isotope dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses were performed on an independent, non-overlapping validation cohort (n = 2149). Complementary isolated human platelet, platelet-rich plasma, whole blood, and animal model studies examined the effect of xylitol on platelet responsiveness and thrombus formation in vivo. Finally, an intervention study was performed to assess the effects of xylitol consumption on platelet function in healthy volunteers (n = 10)., Results: In initial untargeted metabolomics studies (discovery cohort), circulating levels of a polyol tentatively assigned as xylitol were associated with incident (3-year) major adverse cardiovascular event (MACE) risk. Subsequent stable isotope dilution LC-MS/MS analyses (validation cohort) specific for xylitol (and not its structural isomers) confirmed its association with incident MACE risk [third vs. first tertile adjusted hazard ratio (95% confidence interval), 1.57 (1.12-2.21), P < .01]. Complementary mechanistic studies showed xylitol-enhanced multiple indices of platelet reactivity and in vivo thrombosis formation at levels observed in fasting plasma. In interventional studies, consumption of a xylitol-sweetened drink markedly raised plasma levels and enhanced multiple functional measures of platelet responsiveness in all subjects., Conclusions: Xylitol is associated with incident MACE risk. Moreover, xylitol both enhanced platelet reactivity and thrombosis potential in vivo. Further studies examining the cardiovascular safety of xylitol are warranted., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The gut microbiota should be included in the scientific processes of risk assessment of food additives. Xylitol is a sweetener that shows low digestibility and intestinal absorption, implying that a high proportion of consumed xylitol could reach the colonic microbiota. The present study has evaluated the dose-dependent effects of xylitol intake on the composition and the metabolic activity of the child gut-microbiota. The study was conducted in a dynamic simulator of the colonic microbiota (BFBL Gut Simulator) inoculated with a child pooled faecal sample and supplemented three times per day, for 7 days, with increasing xylitol concentrations (1 g/L, 3 g/L and 5 g/L). Sequencing of 16S rRNA gene amplicons and group-specific quantitative PCR indicated a xylitol dose-response effect on the abundance of Lachnospiraceae, particularly the genera Blautia, Anaerostipes and Roseburia. The microbial changes observed with xylitol corresponded with a dose-dependant effect on the butyrate concentration that, in parallel, favoured an increase in epithelial integrity of Caco-2 cells. The study represents a detailed observation of the bacterial taxa that are the main contributors to the metabolism of xylitol by the child gut microbiota and the results could be relevant in the risk assessment re-evaluation of xylitol as a sweetener., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: This study evaluated the effect of xylitol combined or not with fluoride (F) on reduction of demineralization and increase of remineralization of shallow and deep artificial enamel lesions., Methods: Bovine enamel samples were allocated to the following solutions groups: no xylitol (negative control), 5% xylitol, 10% xylitol, 20% xylitol, 500 ppm F (as NaF), 5% xylitol+F, 10% xylitol+F or 20% xylitol+F (n = 12-15). For the demin study, a pH-cycling model (demineralization-6 h, pH 4.7/remineralization 18 h, pH 7.0) was employed for 7 days. Treatments were applied 2 × 1 min. In the remin study, specimens were pre-demineralized for 2, 5 or 10 days. Afterwards, a pH-cycling protocol was conducted (2 h demineralizing and 22 h remineralizing solution/day for 8 days) and the same treatments were done. The response variables were percentage surface hardness loss (%SHL) and transverse microradiography. Data were analyzed by RM ANOVA/Tukey or Kruskal-Wallis/Dunn (p < 0.05) RESULTS: F and Xylitol combined with F reduced the %SHL (23-30%) compared to the negative control (61.5%). The integrated mineral loss and the lesion depth were not reduced by any treatment. Surface hardness recovery was seen only for shallow lesions in case of 20% xylitol+F compared to negative control. No lesion depth recovery, but significant mineral recovery was seen for F (2-days and 10-days lesion)., Conclusions: All concentrations of xylitol+F reduced enamel surface demineralization, while only 20% xylitol+F improved surface remineralization of shallow lesions in vitro., Clinical Significance: Our results suggest that while F or any concentration of xylitol + F reduces surface demineralization, only 20% xylitol+F improves surface remineralization of shallow lesions in vitro. Therefore, xylitol may be added into oral products, combined to F, to control dental caries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relantionships that caould have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)