Cranberry has been widely utilized as a popular botanical dietary supplement to prevent urinary tract infection. The study aims to evaluate the enhanced bactericidal activities of cranberry against uropathogenic Escherichia coli (UPEC) by adding a small quantity of naturally derived antimicrobials. The antibacterial effect was examined with cranberry extract alone (15 and 20%), three kinds of medium-chain fatty acids alone (caprylic, capric, and lauric acid; 0.05–1.0 mM), essential oils alone (carvacrol and thymol; 0.5–1.0 mM), and cranberry extract containing medium-chain fatty acids or essential oils at 37 °C for 1 min. The survivors were remarkably reduced with cranberry extract containing any of the antimicrobials. For example, cranberry extract (15 and 20%) with 1.0 mM of each caprylic acid, lauric acid, and carvacrol resulted in the complete eradication of UPEC (7.55 log reduction). Flow cytometry analysis of UPEC cells exposed to combined treatment showed clear membrane disruption and cell death (>95% of damage). Adding antimicrobials to cranberry extract did not affect (P > 0.05) the characteristics of the cranberry extract (Color, °Brix, pH). The present method may be more acceptable to consumers, who tend to avoid products containing synthetic chemicals and prefer the use of natural agents.

OBJECTIVE: To investigate the effect of cranberry extracts on saliva-derived polymicrobial biofilms with regards to biofilm biomass, acidogenicity, exopolysaccharide (EPS)/microbial biovolumes, colony forming unit (CFU) counts, and the relative abundance of specific caries- and health-associated bacteria.METHODS: Saliva-derived polymicrobial biofilms were grown for 96 h in a cariogenic environment and treated for 2 min every 12 h over the entire biofilm growth period with 500 mug/mL cranberry extract or vehicle control. The effect of the cranberry extract on biofilm behaviour was evaluated using different assays and its influence on key cariogenic and health-associated bacterial populations was assessed with a microarray real-time quantitative PCR method.RESULTS: Cranberry-treated biofilms showed significant drops in biomass (38% reduction, P < 0.001), acidogenicity (44% reduction, P < 0.001), EPS/microbial biovolume ratios (P = 0.033), and CFU counts (51% reduction, P = 0.001). Furthermore, the cranberry extracts effected a significantly lower relative abundance of caries-associated Streptococcus sobrinus (fold change 0.004, P = 0.002) and Provotella denticola (0.002, P < 0.001), and a significantly higher relative abundance of the health-associated Streptococcus sanguinis (fold change 90.715, P = 0.001).CONCLUSIONS: The cranberry extract lowered biofilm biomass, acidogenicity, EPS/microbial biovolumes, CFU counts, and modulated a beneficial microbial ecological change in saliva-derived polymicrobial biofilms.

Phenolic compounds in fruits such as cranberries have been shown to promote a number of biological activities. The purpose of this study was to investigate the effects of polyphenolic compound-containing lingonberry extract on oral streptococci and compare them with the known anti-cariogenic activity of cranberries. Water-soluble and polyphenol-rich fractions (Fractions I and II, respectively) were isolated from cranberries and lingonberries. The effects of those fractions on the biofilm formation ability and bioactivity of Streptococcus mutans MT8148R, Streptococcus sobrinus 6715, and Streptococcus sanguinis ATCC 10556 were then evaluated. Cranberry or lingonberry Fraction II (at 0.5-1 mg/ml) significantly reduced biofilm formation by S. mutans, S. sobrinus, and S. sanguinis. In contrast, cranberry or lingonberry Fraction I (at 0.5-2 mg/ml) increased biofilm formation by S. mutans and S. sobrinus, but not by S. sanguinis. Fractions I and II (at 1-2 mg/ml) also reduced the bioactivity of S. mutans, while Fraction II (at 0.5 mg/ml) enhanced the bioactivity of all tested strains. The results revealed that lingonberries contained a larger amount of polyphenol than cranberries and that they showed almost the same level of activity against the biofilm formation ability and bioactivity of oral streptococci. This indicates that polyphenol-rich lingonberry fraction offers a promising natural food derivative for prevention of dental caries.

Purpose: The purpose of this study was to investigate the effects of polyphenol-rich cranberry extracts on dual-species Streptococcus mutans-Candida. albicans biofilms implicated in contributing to the severity of early childhood caries. Methods: S. mutans-C. albicans biofilms were grown on saliva-coated hydroxyapatite discs (s-HA) mounted on the high-throughput Amsterdam Active Attachment model. The s-HA discs were treated with the cranberry extracts/vehicle control for five minutes just before biofilm growth and subsequently, for similar exposure times, after 12 hours and 24 hours of biofilm growth. The treated 24-hour-old biofilms were then assessed for acidogenicity, metabolic activity, exopolysaccharide (EPS)/microbial biovolumes, structural organization, and colony forming unit (CFU) counts. Results: Treatment with 500 to 1,000 mug/mL of the cranberry extracts produced significant reductions in acidogenicity and metabolic activity (P<0.0001) compared to the control-treated biofilms. A significant decrease in biovolumes of the EPS (P=0.003) and microbial biofilm components (P=0.007) was also seen. Qualitative assessment of confocal biofilm images revealed that the cranberry extract disrupted biofilm structural architecture. Finally, significantly fewer S. mutans (P=0.006) and C. albicans (P=0.036) CFUs were recovered from the cranberry-treated biofilms than from the control-treated bio-films. Conclusions: Cranberry extracts inhibited cariogenic virulence properties of S. mutans-C. albicans dual-species biofilms in an in vitro model.

Antibiotic resistance is spreading at an alarming rate among pathogenic bacteria in both medicine and agriculture. Interfering with the intrinsic resistance mechanisms displayed by pathogenic bacteria has the potential to make antibiotics more effective and decrease the spread of acquired antibiotic resistance. Here, it is demonstrated that cranberry proanthocyanidin (cPAC) prevents the evolution of resistance to tetracycline in Escherichia coli and Pseudomonas aeruginosa, rescues antibiotic efficacy against antibiotic-exposed cells, and represses biofilm formation. It is shown that cPAC has a potentiating effect, both in vitro and in vivo, on a broad range of antibiotic classes against pathogenic E. coli, Proteus mirabilis, and P. aeruginosa. Evidence that cPAC acts by repressing two antibiotic resistance mechanisms, selective membrane permeability and multidrug efflux pumps, is presented. Failure of cPAC to potentiate antibiotics against efflux pump-defective mutants demonstrates that efflux interference is essential for potentiation. The use of cPAC to potentiate antibiotics and mitigate the development of resistance could improve treatment outcomes and help combat the growing threat of antibiotic resistance

Cranberry proanthocyanidin-chitosan composite nanoparticles (PAC-CHT NPs) were formulated using 2:1, 5:1, 10:1, 15:1 20:1, 25:1, and 30:1 PAC to CHT weight ratio to form round shaped particles. The PAC-CHT NPs were characterized by size, polydispersity, surface charge, morphology, and PAC content. PAC-CHT NPs bioactivity was measured by agglutination of extra-intestinal pathogenic Escherichia coli (ExPEC) and inhibition of gut epithelial cell invasion by ExPEC. Results indicate that by increasing the PAC to CHT ratio 10:1 to 30:1 formed stable nanoparticles with diameters of 122.8 to 618.7nm, a polydispersity index of approximated 0.4 to 0.5, and a zeta potential of 34.5 to 54.4mV. PAC-CHT NPs ratio 30:1 agglutinated ExPEC and decreased the ability of ExPEC to invade epithelial cells in a dose-dependent manner. PAC-CHT NPs ratio 10:1 to 30:1 form stable, round-shaped, and bioactive nanoparticles for potential applications in the treatment of ExPEC bacterial infections.

A smart wound dressing based on carrageenan ( kappa C), locust bean gum (LBG), and cranberry extract (CB) for monitoring bacterial wound infections was developed and characterized using UV-vis spectroscopy, FT-IR, and SEM. The mechanical, swelling, cytotoxic and pH sensor properties were also investigated. UV-vis spectra demonstrated that the obtained kappa C:LBG:CB hydrogel film exhibited a visible change of colors as it was immersed in PBS solution pH 5.0, 7.3 and 9.0. The spectra of FT-IR suggested that chemical interactions had occurred between kappa C and CB extract. The obtained kappa C:LBG:CB hydrogel film exhibited adequate mechanical properties and a swelling behavior dependent on pH. Cytotoxicity tests indicated that kappa C:LBG:CB hydrogel film had dose-dependent cytotoxicity against NIH 3T3 fibroblast cells. The in vitro studies using Staphylococcus aureus and Pseudomonas aeruginosa demonstrated that the color changes of the kappa C:LBG:CB hydrogel film could be observed by naked eyes, confirming the potential use of the obtained hydrogel film as a visual system for monitoring bacterial wound infections.

Non-typhoidal Salmonella enterica serovars continue to be an important food safety issue worldwide. Cranberry (Vaccinium macrocarpon Ait) fruits possess antimicrobial properties due to their various acids and phenolic compounds; however, the underlying mechanism of actions is poorly understood. We evaluated the effects of cranberry extracts on the growth rate of Salmonella enterica serovars Typhimurium, Enteritidis and Heidelberg and on the transcriptomic profile of Salmonella Enteritidis to gain insight into phenotypic and transcriptional changes induced by cranberry extracts on this pathogen. An ethanolic extract from cranberry pomaces (KCOH) and two of its sub-fractions, anthocyanins (CRFa20) and non-anthocyanin polyphenols (CRFp85), were used. The minimum inhibitory (MICs) and bactericidal (MBCs) concentrations of these fractions against tested pathogens were obtained using the broth micro-dilution method according to the Clinical Laboratory Standard Institute's guidelines. Transcriptional profiles of S. Enteritidis grown in cation-adjusted Mueller-Hinton broth supplemented with or without 2 or 4 mg/ml of KCOH were compared by RNASeq to reveal gene modulations serving as markers for biological activity. The MIC and MBC values of KCOH were 8 and 16 mg/mL, respectively, against all tested S. enterica isolates. The MIC value was 4 mg/mL for both CRFa20 and CRFp85 sub-fractions, and a reduced MBC value was obtained for CRFp85 (4 mg/ml). Treatment of S. Enteritidis with KCOH revealed a concentration-dependent transcriptional signature. Compared to the control, 2 mg/ml of KCOH exposure resulted in 89 differentially expressed genes (DEGs), of which 53 and 36 were downregulated and upregulated, respectively. The upregulated genes included those involved in citrate metabolism, enterobactin synthesis and transport, and virulence. Exposure to 4 mg/ml KCOH led to the modulated expression of 376 genes, of which 233 were downregulated and 143 upregulated, which is 4.2 times more DEGs than from exposure to 2 mg/ml KCOH. The downregulated genes were related to flagellar motility, Salmonella Pathogenicity Island-1 (SPI-1), cell wall/membrane biogenesis, and transcription. Moreover, genes involved in energy production and conversion, carbohydrate transport and metabolism, and coenzyme transport and metabolism were upregulated during exposure to 4 mg/ml KCOH. Overall, 57 genes were differentially expressed (48 downregulated and 9 upregulated) in response to both concentrations. Both concentrations of KCOH downregulated expression of hilA, which is a major SPI-1 transcriptional regulator. This study provides information on the response of Salmonella exposed to cranberry extracts, which could be used in the control of this important foodborne pathogen.

Recurrent urinary tract infection (rUTI) continues to challenge pediatric care providers. The diagnosis of an rUTI can be difficult, especially in young febrile children. Antibiotic resistance rates continue to rise, which limits oral treatment options. Prophylactic antibiotics are used commonly to manage rUTI, but their use increases the risk of rUTI with antibiotic-resistant strains without significantly reducing renal scarring. Alternative therapies for rUTI include probiotics and anthocyanidins (eg, cranberry extract) to reduce gut colonization by uropathogens and prevent bacterial adhesion to uroepithelia, but efficacy data for these treatments are sparse. The future of rUTI care rests in addressing the following contemporary issues: best diagnostic practices, risk factors associated with rUTI, and the prevention of recurrent infection. In this review, we summarize the state of the art for each of these issues and highlight future studies that will aim to take an alternative approach to managing rUTI.

INTRODUCTION:Urinary tract infections (UTIs) represent a common and costly public health issue. The bacterium Escherichia coli is mainly responsible for most uncomplicated UTIs. Cranberry antibacterial effects have extensively been studied in order to understand the molecular mechanisms of action of its bioactive components and their clinical benefits against UTIs. In this respect, the present review aims to critically analyze the current clinical studies that have evaluated the efficacy of supplementing cranberry products against UTIs in different subpopulations.METHODS:PubMed database was comprehensively searched, using relative keywords in order to identify clinical trials exploring the efficacy of cranberry supplementation against UTIs.RESULTS:Current clinical evidence clearly indicates a possible benefit overall from the use of cranberries against UTIs. Cranberry consumption may prevent bacterial adherence to uroepithelial cells, reducing UTI related symptoms. Cranberry consumption could also decrease UTI related symptoms by suppressing inflammatory cascades as an immunologic response to bacterial invasion. The existing clinical trials have supported substantial evidence that the beneficial effects of cranberry against UTIs seem to be prophylactic by preventing infections recurrence; however, they exert low effectiveness in populations at increased risk for contracting UTIs. Moreover, a lack of cost-effectiveness for cranberry supplementation has been highlighted.CONCLUSIONS:Additional well-designed, double-blind, placebo-controlled clinical trials that use standardized cranberry products for long study periods are strongly recommended in order to determine the efficiency of cranberry on the prevention of UTIs in susceptible populations. At present, cranberry supplementation can safely be suggested as complementary therapy in women with recurrent UTIs.