Cranberry, which is rich in polyphenols, including anthocyanins and proanthocyanidins, has been found to have various effects beneficial to human health, including prevention of urinary tract infections. These effects have been associated with polyphenols in the fruit. We investigated the excretion of anthocyanins in human urine after ingestion of cranberry juice. Eleven healthy volunteers consumed 200 ml of cranberry juice containing 650.8 microg total anthocyanins. Urine samples were collected within 24 h before and after consumption. Six of 12 anthocyanins identified in cranberry were quantified in human urine by HPLC coupled with electrospray ionization and tandem mass spectrometry (HPLC-ESI-MS-MS). Among these, peonidin 3-O-galactoside, the second most plentiful anthocyanin in the juice, was found most abundantly in urine within 24 h, corresponding to 41.5 nmol (56.1% of total anthocyanins). The urinary levels of anthocyanins reached a maximum between 3 and 6 h after ingestion, and the recovery of total anthocyanins in the urine over 24 h was estimated to be 5.0% of the amount consumed. This study found high absorption and excretion of cranberry anthocyanins in human urine.

AIMS: To investigate the effects of berries and berry phenolics on pathogenic intestinal bacteria and to identify single phenolic compounds being responsible for antimicrobial activity.

METHODS AND RESULTS: Antimicrobial activity of eight Nordic berries and their phenolic extracts and purified phenolic fractions were measured against eight selected human pathogens. Pathogenic bacterial strains, both Gram-positive and Gram-negative, were selectively inhibited by bioactive berry compounds. Cloudberry and raspberry were the best inhibitors, and Staphylococcus and Salmonella the most sensitive bacteria. Phenolic compounds, especially ellagitannins, were strong inhibitory compounds against Staphylococcus bacteria. Salmonella bacteria were only partly inhibited by the berry phenolics, and most of the inhibition seemed to originate from other compounds, such as organic acids. Listeria strains were not affected by berry compounds, with the exception of cranberry. Phenolic compounds affect the bacteria in different mechanisms.

CONCLUSIONS: Berries and their phenolics selectively inhibit the growth of human pathogenic bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY: Antimicrobial properties of berries could be utilized in functional foods. Furthermore these compounds would be of high interest for further evaluation of their properties as natural antimicrobial agents for food and pharmaceutical industry

Cranberries have long been the focus of interest for their beneficial effects in preventing urinary tract infections (UTIs). Cranberries contain 2 compounds with antiadherence properties that prevent fimbriated Escherichia coli from adhering to uroepithelial cells in the urinary tract. Approximately 1 dozen clinical trials have been performed testing the effects of cranberries on the urinary tract. However, these trials suffer from a number of limitations. Most importantly, the trials have used a wide variety of cranberry products, such as cranberry juice concentrate, cranberry juice cocktail, and cranberry capsules, and they have used different dosing regimens. Further research is required to clarify unanswered questions regarding the role of cranberries in protecting against UTI in general and in women with anatomical abnormalities in particular.

The majority of infectious diseases are initiated by the adhesion of pathogenic organisms to the tissues of the host. In many cases this adhesion is mediated by lectins present on the surface of the infectious organism that bind to complementary carbohydrates on the surface of the host tissues. Soluble carbohydrates recognized by the bacterial lectins block the adhesion of the bacteria to animal cells in vitro. Moreover, such carbohydrates have been shown to protect against experimental infection by lectin-carrying bacteria of different mammals, such as mice, rabbits, calves, and monkeys. Agents other than carbohydrates also block adhesion, as demonstrated with cranberry juice as well as with low and high molecular weight preparations isolated from the juice. Both kinds of preparation inhibited the adhesion in vitro of Escherichia coli to different animal cells. In addition, the high molecular weight material acted similarly on the adhesion of Helicobacter pylori to human gasrointenstinal cells, and on the coaggregation of oral bacteria. Furthermore, in limited clinical studies regular drinking of cranberry juice had a significant preventive effect on bacteriuria, and the high molecular weight constituent of the juices was also effective in decreasing the salivary level of Streptococus mutans, the major cause of tooth decay. Because the inhibitors of adhesion examined are not bactericidal, the selection of resistant inhibitor strains is unlikely to occur. Together, these findings may lead to new therapeutic strategies that are in dire need because of the world-wide increase in antibiotic resistant bacteria.

The sensitivity of a large number of antibiotic-resistant and nonresistant Helicobacter pylori isolates to the antiadhesion effect of a high-molecular-mass, nondialysable constituent of cranberry juice was tested. Confluent monolayers of gastric cell line in microtiter plate wells were exposed to bacterial suspensions prepared from 83 H. pylori isolates from antibiotic-treated and untreated patients in the presence and absence of the cranberry constituent. Urease assay was used to calculate the percentage of adhesion inhibition. In two thirds of the isolates, adhesion to the gastric cells was inhibited by 0.2 mg/mL of the nondialysable material. There was no relationship between the antiadhesion effect of the cranberry material and metronidazole resistance in isolates from either treated or untreated patients (N=35). Only 13 isolates (16%) were resistant to both the nondialysable material and metronidazole, and 30 (36%) were resistant to the nondialysable material alone. There was no cross-resistance to the nondialysable material and metronidazole. These data suggest that a combination of antibiotics and a cranberry preparation may improve H. pylori eradication.

Several forces are driving an expanded use of nutraceuticals, particularly functional foods and probiotics, as instruments of the restoration and maintenance of well-being. These include consumer desire to use natural rather than pharmaceutical products, the mounting scientific evidence that shows efficacy of certain nutraceutical products, and the increasing cost and continued failure of drugs to cure or prevent disease. There is now a strong scientific basis for use of cranberries to reduce the risk of E. coli adhesion to bladder cells and the onset of urinary tract infection. There is also a mechanistic basis and clinical support for use of Lactobacillus strains such as L. rhamnosus GR-1 and L. fermentum RC-14 to colonize the intestine and vagina and reduce the risk of intestinal and urogenital infections. For such alternative approaches to be successful, scientific rigor must be backed by public education and physician acceptance. Given the emergence of virulent and multidrug-resistant pathogens, time is not on our side.

Previous investigations showed that a high molecular mass, non-dialyzable material (NDM) from cranberries inhibits the adhesion of a number of bacterial species and prevents the co-aggregation of many oral bacterial pairs. In the present study we determined the effect of mouthwash supplemented with NDM on oral hygiene. Following 6 weeks of daily usage of cranberry-containing mouthwash by an experimental group (n = 29), we found that salivary mutans streptococci count as well as the total bacterial count were reduced significantly (ANOVA, P 0.01) compared with those of the control (n = 30) using placebo mouthwash. No change in the plaque and gingival indices was observed. In vitro, the cranberry constituent inhibited the adhesion of Streptococcus sobrinus to saliva-coated hydroxyapatite. The data suggest that the ability to reduce mutans streptococci counts in vivo is due to the anti-adhesion activity of the cranberry constituent.

No abstract - The high-molecular-weight inhibitor of adhesin was partially purified from cranberry juice by gel-filtration chromatography. The product was heat-stable, resistant to trypsin, and nondialysable, and it inhibited the MR adhesin of al 20 urinary isolates tested in concentrations of 12 to 25 µg per milliliter. On the basis of these results, together with those of earlier studies, we suggest that the antiadhesive agents in juices from vaccinium berries may act in the gut (the source of most uropathogens), in the bladder, or both by preventing colonization of these sites.

Dental biofilm harbouring oral bacteria is highly correlated with the progression of dental diseases. Disruption of biofilm formation via anti-adhesion agents is an alternative means to the antibacterial approach. Previous studies have shown that high molecular weight non-dialysable material (NDM) derived from cranberry juice inhibits the adhesion of Escherichia coli and the coaggregation of a variety of oral bacteria. In addition, it inhibits the formation of glucans and fructans synthesised by GTF and FTF. In the present study, we examined the anti-adhesion effect of NDM on S. sobrinus. NDM promoted desorption of S. sobrinus from biofilm in the presence and absence of extracellular glucans and fructans, although the effect was more pronounced in the absence of these polysaccharides. Precoating of the bacteria with NDM reduced their ability to form biofilm. Our results indicate that NDM could be exploited as an anti-biofilm agent.

Cranberry juice contains high molecular weight materials (NDM) that inhibit bacterial adhesion to host cells as well as the co-aggregation of many oral bacteria. Because of its broad-spectrum activity, we investigated NDM's potential for inhibiting influenza virus adhesion to cells, and subsequent infectivity. Hemagglutination (HA) of red blood cells (RBC) caused by representatives of both influenza virus A subtypes (H1N1)and H3N2) and the B type was inhibited by NDM at concentrations of 125 microg/ml or lower, which is at least 20-fold lower than that usually found in cranberry juice. A dose-response effect of NDM on HA was demonstrated. The infectivity of the A and B types was significantly reduced by preincubation with NDM (250 microg/ml), as reflected by the lack of cytopathic effect on Madine-Darby canine kidney (MDCK) cells and the lack of HA activity in the media of infected cells. The effect of NDM was also tested after A or B type viruses were allowed to adsorb to and penetrate the cells. Various levels of reduction in virus tissue culture infective dose TCID50 were observed. The effect was most pronounced when NDM was added several times to the infected MDCK cells. Our cumulative findings indicate that the inhibitory effect of NDM on influenza virus adhesion and infectivity may have a therapeutic potential.