Cranberries have long been the focus of interest for their beneficial effects in preventing urinary tract infections (UTIs). The objective of this study was to determine in vitro activity of cranberry extract on common etiologic agents of urinary tract infections isolated from patients. Filter sterilized methanol extract of cranberry was prepared and used in the present study. The minimum inhibitory concentration (MIC) was evaluated for active crude extract. The MIC value of methanol extract were 0.391 mg/ml for
Enterobacter aerogenes and Staphylococcus aureus whereas the MIC of methanol extract of cranberry were 1.2500 and 0.0195 mg/ml for Escherichia coli and Klebsiella pneumoniae respectively. The lower MIC value of cranberry extract against K. pneumoniae in comparison to other three organisms suggests that K. pneumoniae showed greater sensitivity towards the extracts of the cranberry extract.

Ethyl acetate extracts of Sephadex LH20-purified proanthocyanidins of American cranberry (Vaccinium macrocarpon Ait.) exhibited potent biological activity by inhibiting adherence of uropathogenic isolates of P-fimbriated Escherichia coli bacteria to cellular surfaces containing a-Gal(1 4 4)b-Gal receptor sequences similar to those on epithelial cells in the urinary tract. The chemical structures of the proanthocyanidins were determined by 13C NMR, electrospray mass spectrometry, matrix-assisted
laser absorption time-of-flight mass spectrometry and by acid catalyzed degradation with phloroglucinol. The proanthocyanidin molecules consisted predominantly of epicatechin units with mainly DP of 4 and 5 containing at least one A-type linkage. The procyanidin A2 was the most common terminating unit occurring about four times as frequently as the epicatechin monomer

Cranberry and its products are important components of the cranberry processing industry and have historically been associated with positive health benefits such as preventing urinary tract infections. These health benefits are associated with phenolic phytochemicals in the juice which are now known to have potential for inhibition of development and progression of cancer and cardiovascular diseases. Helicobacter pylori is an important human pathogen linked to peptic ulcer and now to cardiovascular diseases. Control of this pathogen using synthetic antimicrobials such as currently approved antibiotics has limitations due to potential development of resistance and low compliance. We believe a profile of antimicrobials compared to a single compound could be potentially more effective in managing H. pylori infections. We have investigated the effect of cranberry, blueberry and grape seed extracts on inhibiting H. pylori have been investigated. The ability of blueberry, grape seed and oregano extract on enhancing the antioxidant and anti-H. pylori activity of cranberry powder in a mixture was also investigated. The anti-H. pylori activity of the cranberry fruit extracts and their synergies correlated with antioxidant activity and the presence of biphenyls as well as polyphenolic phytochemicals. The anti-H. pylori activity of cranberry juice extract was significantly improved by its synergistic blending with blueberry, grape seed and oregano extract. The lower efficacy of purified phenolics in inhibiting H. pylori compared with fruit powder at similar dosage levels suggests a synergistic mode of functionality of these individual phenolics in whole food background. Consumption of blends of fruit juices with other fruit as well as herb extracts can impart unique functional attributes and could be an effective strategy in developing diet-based management of H. pylori infections as well as other oxidation linked diseases.

Cranberry fruit is a rich source of polyphenols, and has shown biological activities against Streptococcus mutans. In the present study, we examined the influence of extracts of flavonols (FLAV), anthocyanins (A) and proanthocyanidins (PAC) from cranberry on virulence factors involved in Streptococcus mutans biofilm development and acidogenicity. PAC and FLAV, alone or in combination, inhibited the surface-adsorbed glucosyltransferases and F-ATPases activities, and the acid production by S. mutans cells. Furthermore, biofilm development and acidogenicity were significantly affected by topical applications of PAC and FLAV (P0.05). Anthocyanins were devoid of any significant biological effects. The flavonols are comprised of mostly quercetin glycosides, and the PAC are largely A-type oligomers of epicatechin. Our data show that proanthocyanidins and flavonols are the active constituents of cranberry against S. mutans.

Several studies have shown the antimutagenic DNA protective functions of some naturally occurring phenolic phytochemicals. Emerging research also indicates that synergistic functionality of these phytochemicals in whole foods benefits the management of many diseases. This study investigated the potential antimutagenic properties of cranberry phenolics, ellagic acid (EA), rosmarinic acid (RA) and their synergistic interactions on enhancing the antimutagenic properties in Salmonella typhimurium tester system against the mutagens sodium azide and N-methyl-N'-nitro-N-nitrosoguanidine. The ability of these phytochemical treatments to protect oxidative damage to DNA was also investigated using the supercoiled DNA strand scission assay. The results showed that EA was most effective in inhibiting the mutations in S. typhimurium system, whereas RA and EA were equally effective in protecting the DNA from oxidative damage. In addition, the antimutagenic activity of cranberry powder (CP) made from juice extracts was significantly enhanced when 30% (w/w) of phenolics in CP was substituted with RA and EA, possibly because of synergistic redox modulation that can influence mutagen function. It was also suggested that the synergistic mixture of cranberry phenolics with RA could also be protecting the cell from mutations by modulating the DNA repair systems

Cranberry, the fresh or dried ripe fruit of Vaccinium macrocarpon Ait. (Ericaceae), is currently used as adjunct therapy for the prevention and symptomatic treatment of urinary tract infections. Data from clinical trials suggest that extracts of cranberry or cranberry juice reduce the bacterial load of E. coli and also suppress the inflammatory symptoms induced by E. coli infections. A methanol extract prepared from 10 kg of dehydrated cranberries did not directly inhibit the growth of E coli strains ATCC 700336 or ATCC 25922 in concentrations up to 256 mug/mL in vitro. However, the methanol extract (CR-ME) inhibited the activity of cyclooxygenase-2, with an IC(50) of 12.8 mug/mL. Moreover, CR-ME also inhibited the NF-kappabeta transcriptional activation in human T lymphocytes with an IC(50) of 19.4 mug/mL, and significantly (p 0.01) inhibited the release of interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor-alpha from E. coli lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells in vitro, at a concentration of 50 mug/mL. The extract had no effect on inducible nitric oxide synthase activity in the murine macrophage cell line RAW 264.7. The compounds responsible for this activity were identified using a novel LC-MS based assay as ursolic acid and ursolic acid derivatives. Taken together, these data suggest CR-ME and its constituent chemical compounds target specific pathways involved in E. coli-induced inflammation.

CONTEXT: Cranberry juice has long been recognized in folk medicine as a therapeutic agent, mainly in urinary tract infections. Its proposed mechanism of action is antiadhesion of bacteria.

OBJECTIVE: Investigation of the potential antiadhesion effect of nondialyzed material of cranberry (NDM) via its influence on secretion, gene expression, and promoter activity of the fructosyltransferase (FTF), which is among the extracellular enzymes associated with dental biofilm formation and pathogenesis of oral bacteria.

MAIN OUTCOME MEASURES: Secretion of FTF from Streptococcus mutans, in the presence of NDM, was measured by immunoblotting and confocal scanning laser microscopy. Its influence on ftf gene expression was determined by reverse transcription followed by real-time RT-PCR. The luciferase assay was used to detect bioluminescence expressed by the ftf promoter activity of bacteria exposed to NDM.

RESULTS: NDM at concentrations between 0.2/mL and 1mg/mL significantly (P.05) decreased secretion of extracellular FTF, as well as down-regulated ftf expression in a dose-dependent manner. NDM also markedly reduced the luciferase activity under the ftf promoter.

Cranberry juice has long been recognized in folk medicine as a therapeutic agent, mainly in urinary track infections. It acts as an antibiofilm agent against various pathogens. Quorum sensing is process where bacteria communicate with each other via signal molecules known as autoinducers. This process is strongly involved in various bacterial pathological and physiological pathways. Various strains of Vibrio harveyi bacteria were incubated with different concentrations of nondialyzable material of cranberry (NDM) with or without addition of exogenous autoinducer. Bioluminescence regulated by the autoinducers was measured in GENios reader. Effect of NDM alone or NDM supplemented with autoinducer on quorum sensing was determined as change in bioluminescence in each treated sample compared to appropriate control in every strain. Using model of V. harveyi, we found an inhibitory effect of cranberry constituents on bacterial signaling system. This effect was reversible, since exogenous autoinducer was able to recover bioluminescence which was decreased by NDM. We hypothesized that cranberry NDM interacts with V. harveyi quorum sensing by competition with autoinducer

PURPOSE: Vaccinium macrocarpon--the American cranberry--irreversibly inhibits the expression of P-fimbriae of E. coli. Further effects on the function and expression of P-fimbriae were studied by growing P-fimbriated E. coli in solid media laced with cranberry juice.

METHODS: Cranberry concentrate at pH 7.0 was added to CFA medium to a final concentration of 25%. E. coli strains JR1 and DS17 were plated on this medium with a plain CFA control and incubated at 37C. Cultures were tested for ability to agglutinate P-receptor specific beads. Bacteria were washed in PBS and agglutination retested. Cultures were also replated on plain CFA agar and rechecked for their ability to agglutinate. Transmission electron micrographs were performed on positive control and test bacteria.

RESULTS: For E. coli strain JR1, P-fimbrial agglutination was inhibited after the third plating. DS17 was fully inhibited after the second plating. Washing in PBS did not affect agglutination, but replating on CFA agar allowed agglutination to recur. Electron micrographic study of control populations confirmed fimbriae. Fully inhibited bacteria had a 100% reduction in expression of fimbriae. Additionally, inhibited bacteria showed cellular elongation.

CONCLUSIONS: Cranberry juice irreversibly inhibits P-fimbriae. Electron micrographic evidence suggests that cranberry juice acts on the cell wall preventing proper attachment of the fimbrial subunits or as a genetic control preventing the expression of normal fimbrial subunits or both.

Because previous studies have shown that a high molecular mass constituent of cranberry juice inhibited adhesion of Escherichia coli to epithelial cells and coaggregation of oral bacteria, we have examined its effect on the adhesion of Helicobacter pylori to immobilized human mucus and to erythrocytes. We employed three strains of H. pylori all of which bound to the mucus and agglutinated human erythrocytes via a sialic acid-specific adhesin. The results showed that a high molecular mass constituent derived from cranberry juice inhibits the sialic acid-specific adhesion of H. pylori to human gastric mucus and to human erythrocytes.