PURPOSE: To assess the effects of NDM from cranberries on Staphylococcus epidermidis biofilm formed on soft contact lenses.

METHODS: Soft contact lenses were incubated in Tryptic Soy Broth (TSB) together with S. epidermidis (ATCC35984/RP62A) and various concentrations of NDM, and inspected by scanning electron and confocal microscopy. The TSB was collected after sonification and monitored turbidometrically.

RESULTS: NDM at >=500 mug/mL concentration caused a significant (P 0.01) reduction of biofilm. Scanning electron microscopy of biofilm in the presence of 500 to 1000 mug/mL NDM confirmed these results. In control lenses, multilayered mushroom-shaped biofilm and complete coverage of the lens surface were seen, whereas after incubation with 500 mug NDM per mL TSB, the biofilm was thinner with smaller protuberances, and exposed lens surface was partially seen. In samples incubated with 1000 mug NDM per mL TSB, the lens surface was clearly seen between sporadic microcolonies.

CONCLUSIONS: NDM reduces formation of biofilm on soft contact lenses. This has important implications for the prevention of contact lens-related corneal infections caused by S. epidermidis.

Bacterial motility plays a key role in the colonization of surfaces by bacteria and the subsequent formation of resistant communities of bacteria called biofilms. Derivatives of cranberry fruit, predominantly condensed tannins called proanthocyanidins (PACs) have been reported to interfere with bacterial adhesion, but the effects of PACs and other tannins on bacterial motilities remain largely unknown. In this study, we investigated whether cranberry PAC (CPAC) and the hydrolyzable tannin in pomegranate (PG; punicalagin) affected the levels of motilities exhibited by the bacterium Pseudomonas aeruginosa. This bacterium utilizes flagellum-mediated swimming motility to approach a surface, attaches, and then further spreads via the surface-associated motilities designated swarming and twitching, mediated by multiple flagella and type IV pili, respectively. Under the conditions tested, both CPAC and PG completely blocked swarming motility but did not block swimming or twitching motilities. Other cranberry-containing materials and extracts of green tea (also rich in tannins) were also able to block or impair swarming motility. Moreover, swarming bacteria were repelled by filter paper discs impregnated with many tannin-containing materials. Growth experiments demonstrated that the majority of these compounds did not impair bacterial growth. When CPAC- or PG-containing medium was supplemented with surfactant (rhamnolipid), swarming motility was partially restored, suggesting that the effective tannins are in part acting by a rhamnolipid-related mechanism. Further support for this theory was provided by demonstrating that the agar surrounding tannin-induced nonswarming bacteria was considerably less hydrophilic than the agar area surrounding swarming bacteria. This is the first study to show that natural compounds containing tannins are able to block P. aeruginosa swarming motility and that swarming bacteria are repelled by such compounds.

Traditional first-line treatment of chronic bacterial prostatitis (CBP) is administration of empirical antibiotics. However, the efficacy rate is low and long-term antibiotic therapy can result in adverse events and bacterial resistance. For these reasons, a new treatment or preventive modality that can replace traditional antibiotic therapy is required. There are several reports that E. coli extract has a preventive effect on recurrent urinary tract infection (UTI). Cranberries are also known to have beneficial effects in preventing UTI. To evaluate the preventive effect of E. coli extract and cranberries on CBP, 48 rats were randomly divided into 4 groups; control, ciprofloxacin, E. coli extract, and cranberry groups. All drug treatments were conducted for 3 weeks, and then we developed a CBP rat model. After 4 weeks, the results of microbiological culture of prostate and urine samples as well as histological findings for the prostate were analyzed for each group. The infection rate in the ciprofloxacin group was significantly lower than that in the control group. The microbiological cultures of the prostate and urine samples demonstrated reduced bacterial growth in all experimental groups compared with the control group. Histopathologic examination showed significantly decreased prostatic inflammation in all groups compared with the control group. These results suggest that E. coli extract has a potential preventive effect on the development of CBP, and cranberry also exhibits promising activity in this context

The effects of the industrial juice process on the ability of neutralized cranberry samples and extracts (polar, apolar and anthocyanins) to inhibit the growth of Enterococcus faecium resistant to vancomycin (ERV), Escherichia coli O157:H7 EDL 933, E. coli ATCC 25922, Listeria monocytogenes HPB 2812, Pseudomonas aeruginosa ATCC 15442, Salmonella Typhimurium SL1344 and Staphylococcus aureus ATCC 29213 were investigated. The juice process appeared to have a general enhancing effect on the antibacterial properties of cranberry polar and anthocyanin extracts. The lowest minimum inhibitory concentrations (MICs) (1.80-7.0 micro g phenol/well) were obtained when S. aureus, S. Typhimurium, and ERV were exposed to the juice concentrate. The growth of P. aeruginosa, L. monocytogenes, E. coli ATCC, and E. coli O157:H7 was not inhibited by the juice concentrate, but did show sensitivity (maximal tolerated concentrations of 0.007-0.4 micro g phenol/well). The lowest MICs (22.6-90.5 micro g phenol/well) for P. aeruginosa, S. aureus, S. Typhimurium, and ERV were observed when they were exposed to the cranberry anthocyanin extract obtained from cranberry pomace. The results also showed a negative effect of the juice process on the antibacterial properties of the cranberry apolar extracts: the one obtained from frozen cranberries was most efficient against P. aeruginosa, S. aureus, L. monocytogenes and S. Typhimirium (MIC of 45.50 micro g phenol/well). The tested bacteria showed the greatest resistance toward the cranberry extracts obtained from the mash and the macerated and depectinized mash

Transcriptional profiles of uropathogenic Escherichia coli CFT073 exposed to cranberry-derived proanthocyanidins (PACs) were determined. Our results indicate that bacteria grown on media supplemented with PACs were iron deprived. To our knowledge, this is the first time that PACs have been shown to induce a state of iron limitation in this bacterium.

In humans, uropathogenic Escherichia coli (UPEC) is the most common etiological agent of uncomplicated urinary tract infections (UTIs). Cranberry extracts have been linked to the prevention of UTIs for over a century; however, a mechanistic understanding of the way in which cranberry derivatives prevent bacterial infection is still lacking. In this study, we used a fliC-lux reporter as well as quantitative reverse transcription-PCR to demonstrate that when UPEC strain CFT073 was grown or exposed to dehydrated, crushed cranberries or to purified cranberry-derived proanthocyanidins (cPACs), expression of the flagellin gene (fliC) was inhibited. In agreement with these results, transmission electron microscopy imaging of bacteria grown in the presence of cranberry materials revealed fewer flagella than those in bacteria grown under control conditions. Furthermore, we showed that swimming and swarming motilities were hindered when bacteria were grown in the presence of the cranberry compounds. Because flagellum-mediated motility has been suggested to enable UPEC to disseminate to the upper urinary tract, we propose that inhibition of flagellum-mediated motility might be a key mechanism by which cPACs prevent UTIs. This is the first report to show that cranberry compounds inhibit UPEC motility via downregulation of the fliC gene. Further studies are required to establish whether these inhibitors play a role in vivo.

The various health benefits of Vaccinium macrocarpon (cranberry) are well documented and have been attributed mainly to its antioxidant capacity and anti-adhesive activity. Several different mechanisms have been proposed to explain the possible role of cranberries, cranberry juice, and cranberry extracts in inhibiting bacterial growth. These mechanisms of action (i.e., inhibition of the microbial growth) have not been thoroughly studied. Here, we took advantage of current advances in microarray technology and used GeneChip® Escherichia coli genome 2.0 arrays to gain insight into the molecular mechanisms involved in the impact of cranberry juice on the properties of E. coli growth. The inclusion of cranberry juice in bacterial growth media was found to significantly impact the doubling time of E. coli. The gene expression results revealed altered expression of genes associated with iron transport and essential metabolic enzymes as well as with adenosine triphosphate (ATP) synthesis and fumarate hydratase in these cultures. The altered expression of genes associated with iron transport was consistent with the strong iron chelating capability of proanthocyanidins, a major constituent of cranberry juice. The iron depletion effect was confirmed by adding exogenous iron to the growth media. This addition partially reversed the inhibitory effect on bacterial growth observed in the presence of cranberry juice/extracts.

Background: The increasing prevalence of uropathogens resistant to antimicrobial agents has stimulated interest in cranberries to prevent recurrent urinary tract infections (UTIs). Methods: In a double-blind, double-dummy noninferiority trial, 221 premenopausal women with recurrent UTIs were randomized to 12-month prophylaxis use of trimethoprim-sulfamethoxazole (TMP-SMX), 480 mg once daily, or cranberry capsules, 500 mg twice daily. Primary end points were the mean number of symptomatic UTIs over 12 months, the proportion of patients with at least 1 symptomatic UTI, the median time to first UTI, and development of antibiotic resistance in indigenous Escherichia coli. Results: After 12 months, the mean number of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (4.0 vs 1.8; P=.02), and the proportion of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (78.2% vs 71.1%). Median time to the first symptomatic UTI was 4 months for the cranberry and 8 months for the TMP-SMX group. After 1 month, in the cranberry group, 23.7% of fecal and 28.1% of asymptomatic bacteriuria E. coli isolates were TMP-SMX resistant, whereas in the TMP-SMX group, 86.3% of fecal and 90.5% of asymptomatic bacteriuria E. coli isolates were TMP-SMX resistant. Similarly, we found increased resistance rates for trimethoprim, amoxicillin, and ciprofloxacin in these E. coli isolates after 1 month in the TMP-SMX group. After discontinuation of TMP-SMX, resistance reached baseline levels after 3 months. Antibiotic resistance did not increase in the cranberry group. Cranberries and TMP-SMX were equally well tolerated. Conclusion: In premenopausal women, TMP-SMX, 480 mg once daily, is more effective than cranberry capsules, 500 mg twice daily, to prevent recurrent UTIs, at the expense of emerging antibiotic resistance.

Urinary tract infections (UTI) are common in childhood. In 30-50% of children with UTI the infections occur recurrently, especially in those with vesicoureteral reflux (VUR), neurogenic bladder (NB), previous cystitis or pyelonephritis and malformative uropathies. To reduce the likelihood of UTI, antibiotic prophylaxis has been regarded as the therapeutic standard for many years. However, the disadvantage of long-term antibiotic therapy is the potential for development of collateral effects and resistant organisms in the host. Such reasons have induced scientists to search for alternative modalities of UTI prevention and have contributed to determining the increasing desire for "naturalness" of the population and preventing excessive medication. The use of cranberry fulfils these needs by potentially replacing or enhancing traditional procedures. The purpose of this study was to assess the effectiveness of cranberry in preventing UTI in pediatric populations. We searched Pubmed, the Cochrane Central Register of Controlled Trials and Internet. Cranberry in patients with previous UTI was evaluated in three studies, cranberry in patients with VUR in three studies and four studies analyzed the efficacy of cranberry in children with NB. In seven of nine studies cranberry had a significant effect in preventing UTI.

The glycosides of flavonoid, anthocyanins and A type proanthocyanidins in cranberry concentrate were characterized and quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Cranberry concentrate (1 g/body weight) was orally gavaged to Fischer-344 rats (n = 6), and blood and urine samples were collected over 24 h periods. Quercetin, 3'-O-methylquercetin (isorhamnetin), myricetin, kaempferol, and proanthocyanidin dimer A2, together with thirteen conjugated metabolites of quercetin and methylquercetin and intact peonidin 3-O-galactoside and cyanidin 3-O-galactoside were identified in the rat urine after cranberry treatment. Very low levels of isorhamnetin (0.48 +/- 0.09 ng/mL) and proanthocyanidin dimer A2 (0.541 +/- 0.10 ng/mL) were found in plasma samples after 1 h of cranberry administration. Although no quercetin was detected in plasma, MRM analysis of the methanolic extract of urinary bladder showed that chronic administration of cranberry concentrate to rats resulted in accumulation of quercetin and isorhamnetin in the bladder. These results demonstrate that cranberry components undergo rapid metabolism and elimination into the urine of rats and are present in the urinary bladder tissue potentially allowing them to inhibit urinary bladder carcinogenesis.