Cranberry juice (CJ) has biological properties that may provide health benefits. In this study, we investigated the influence of CJ (pH 5.5) on several activities in vitro associated with the development of Streptococcus mutans UA159 biofilms. The ability of CJ to influence the adherence of S. mutans to either saliva- (sHA) or glucan-coated hydroxyapatite (gsHA), and to inhibit the glucan production by purified glucosyltransferases adsorbed to sHA was determined. For the adherence assays, we used both uncoated and saliva-coated bacterial cells. Furthermore, we examined whether CJ interferes with the viability, development, polysaccharide composition and acidogenicity of S. mutans biofilms. A solution containing equivalent amounts of glucose, fructose and organic acids at pH 5.5 was used as negative control. The adherence of S. mutans (uncoated and saliva-coated) to either sHA or gsHA treated with 25% CJ (v/v) was remarkably reduced (40-85% inhibition compared to control: p 0.05), indicating that CJ effectively blocked the bacterial adherence to binding sites in salivary pellicle and in glucans. In contrast, when the bacterial cells alone were treated with CJ they adhered to the similar untreated surfaces. Cranberry juice (25%, v/v) also inhibited the activities of surface-adsorbed GTF B and C (70-80% inhibition compared to control, p 0.05). The effect of CJ on the viability of microorganisms in biofilms was not significant. Biofilm formation and accumulation were significantly reduced by topical applications of 25% CJ (v/v) twice daily with 1-min exposures (p 0.05). The biomass and insoluble glucan content of the biofilms in addition to its acidogenicity were significantly reduced by cranberry treatments (p 0.05). Our data show that cranberry juice inhibited glucan-mediated biofilm development and acid production, and holds promise as a natural product to prevent biofilm-related oral diseases.

Cranberry crude extracts, in various vehicles, have shown inhibitory effects on the formation of oral biofilms in vitro. The presence of proanthocyanidins (PAC) in cranberry extracts has been linked to biological activities against specific virulence attributes of Streptococcus mutans, e.g. the inhibition of glucosyltransferase (Gtf) activity. The aim of the present study was to determine the influence of a highly purified and chemically defined cranberry PAC fraction on S. mutans biofilm formation on saliva-coated hydroxyapatite surface, and on dental caries development in Sprague-Dawley rats. In addition, we examined the ability of specific PAC (ranging from low-molecular-weight monomers and dimers to high-molecular-weight oligomers/polymers) to inhibit GtfB activity and glycolytic pH drop by S. mutans cells, in an attempt to identify specific bioactive compounds. Topical applications (60-second exposure, twice daily) with PAC (1.5 mg/ml) during biofilm formation resulted in less biomass and fewer insoluble polysaccharides than the biofilms treated with vehicle control had (10% ethanol, v/v; p 0.05). The incidence of smooth-surface caries in rats was significantly reduced by PAC treatment (twice daily), and resulted in less severe carious lesions compared to the vehicle control group (p 0.05); the animals treated with PAC also showed significantly less caries severity on sulcal surfaces (p 0.05). Furthermore, specific A-type PAC oligomers (dimers to dodecamers; 0.1 mg/ml) effectively diminished the synthesis of insoluble glucans by GtfB adsorbed on a saliva-coated hydroxyapatite surface, and also affected bacterial glycolysis. Our data show that cranberry PAC reduced the formation of biofilms by S. mutans in vitro and dental caries development in vivo, which may be attributed to the presence of specific bioactive A-type dimers and oligomers.

BACKGROUND AND OBJECTIVE: The purpose of this study was to investigate the effects of cranberry polyphenol fraction on biofilm formation and activities of Arg-gingipain and Lys-gingipain in Porphyromonas gingivalis.

MATERIAL AND METHODS: The polyphenol fraction was prepared by using a glass column packed with Amberlite XAD 7HP and 70% aqueous ethanol as an elution solvent.

RESULTS: Synergistic biofilm formation by P. gingivalis and Fusobacterium nucleatum was significantly inhibited by the polyphenol fraction at a concentration of 250 microg/mL compared with untreated controls (p 0.01). Arg-gingipain and Lys-gingipain activities in P. gingivalis ATCC 33277 and FDC 381 were inhibited significantly at a polyphenol fraction concentration of > or = 1 microg/mL (p 0.05).

CONCLUSION: These findings indicate that the polyphenol fraction inhibits biofilm formation and the Arg-gingipain and Lys-gingipain activities of P. gingivalis.

Cranberry juice is known to inhibit bacterial adhesion. We examined the inhibitory effect of cranberry juice on the adhesion of oral streptococci strains labeled with [3H]-thymidine to saliva-coated hydroxyapatite beads (s-HA). When the bacterial cells were momentarily exposed to cranberry juice, their adherence to s-HA decreased significantly compared with the control (P 0.01). Their hydrophobicity also decreased dependently with the concentration of cranberry juice. We also evaluated the inhibitory effect of cranberry juice on biofilm formation. By using a microplate system, we found that the high molecular mass constituents of cranberry juice inhibited the biofilm formation of the tested streptococci. The inhibitory activity was related to the reduction of the hydrophobicity. The present findings suggest that cranberry juice component(s) can inhibit colonization by oral streptococci to the tooth surface and can thus slow development of dental plaque.

No abstract - Introduction: Urinary tract infections (UTI) are the commonest bacterial infection in older people. Half of all women experience at least one UTI and the risk increases with age. The present management of recurrent urinary tract infection is prophylaxis with low-dose, long-term antibiotics. However, there is a growing reluctance to prescribe antibiotics unless absolutely essential because of fears about antimicrobial resistance. So the recent resurgence in interest in the potential role of cranberry
products is timely.

No abstract - Introduction: Cranberry (Vacinicum macrocarpon) is traditionally used in folk medicine for treatment of urinary tract infections. In a recent study, we established that in addition to the antiadhesion effects, concentrated cranberry juice had a direct antimicrobial effect in vitro. We were also able to confirm a direct antimicrobial activity in vitro against a strain of Klebsiella
pneumoniae, in the urine of subjects after ingestion of a commercial cranberry product. While bacteria are the most common cause of urinary tract infections, frequent or prolonged antimicrobial therapy, use of catheters, severely ill patients, high plasma glucose, and invasive procedures can often lead to candiduria. A review of the literature identified one study (Swartz and Medrek 1968), which reported that cranberry juice (40%) in Sabouraud’s dextrose agar had minimal effect on the growth of Candida albicans compared to 0.087% benzoic acid. In this study, we evaluate the anti-Candida activity of urine specimens after ingestion of cranberry.

Three proanthocyanidin trimers possessing A-type interflavanoid linkages, epicatechin-(4beta-->6)-epicatechin-(4beta-->8, 2beta-->O-->7)-epicatechin (4), epicatechin-(4beta-->8, 2beta-->O-->7)-epicatechin-(4beta-->8)-epicatechin (5), and epicatechin-(4beta-->8)-epicatechin-(4beta-->8, 2beta-->O-->7)-epicatechin (6), were isolated from the ripe fruits of Vaccinium macrocarpon (cranberry) and prevented adherence of P-fimbriated Escherichia coli isolates from the urinary tract to cellular surfaces containing alpha-Gal(1-->4)beta-Gal receptor sequences similar to those on uroepithelial cells. The structure of 4 was elucidated by a combination of spectroscopic methods and acid-catalyzed degradation with phloroglucinol. Also isolated were the weakly active epicatechin-(4beta-->8, 2beta-->O-->7)-epicatechin (procyanidin A2) (3) and the inactive monomer epicatechin (1) and the inactive dimer epicatechin-(4beta-->8)-epicatechin (procyanidin B2) (2).

BACKGROUND: Urinary tract infections (UTIs) are extremely prevalent and despite treatment with antibiotics, reoccurrences are common causing frustration in the patient and the potential for developing antibiotic resistance. The use of cranberry products to prevent UTIs has recently become popular and more clinical studies are needed to explore this use.

OBJECTIVE: This open label pilot study examined the ability of a concentrated cranberry preparation to prevent UTIs in women with a history of recurrent infections.

SUBJECTS: Women between the ages of 25 and 70 years old were included with a history of a minimum of 6 UTIs in the proceeding year.

INTERVENTION: The women took one capsule twice daily for 12 weeks containing 200 mg of a concentrated cranberry extract standardized to 30% phenolics.

DESIGN: A questionnaire was used initially to determine the patient's medical history and they were asked at monthly intervals if any of the information had changed. All of the women in the study had urinalysis within 24h before starting on the study preparation and once a month after that for 4 months. Subjects were followed-up approximately 2 years later.

RESULTS: All 12 subjects participated in the 12-week study and were available for follow up 2 years later. During the study none of the women had a UTI. No adverse events were reported. Two years later, eight of the women who continue to take cranberry, continue to be free from UTIs.

CONCLUSION: A cranberry preparation with a high phenolic content may completely prevent UTIs in women who are subject to recurrent infections.

PMID: 17296290 [PubMed - indexed for MEDLINE]

No abstract - Introduction: Urinary tract infection (UTI) is a common childhood infection. In 30–50% of children with UTI the infections occur recurrently, especially in those with vesicoureteral reflux (VUR), resulting in hospitalizations, and long-term health problems, such as renal scars, hypertension, and end-stage renal disease. To reduce the likelihood of recurrent UTI for children with VUR, antibiotics 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 resistant organisms in the host.

Although cranberry juice prophylaxis was found to reduce the frequency of bacteriuria with pyuria in older women, no studies have yet been reported in the literature on children with VUR. The purpose of this study was to examine whether cranberry juice can be substituted for antibiotic prophylaxis in the prevention of UTI in children with VUR.

BACKGROUND AND AIM: Cranberry is a fruit that originated in North America, and it has been used by Native Americans for bacterial infections. Recent studies have revealed it to be effective for preventing refractory urinary infections, while also suggesting that it plays a possible role in the eradication of Helicobacter pylori (H. pylori).

METHODS: The H. pylori strains used in the present study were NCTC11637 and 11638. Sugar and organic acid-rich, and polyphenol-rich fractions were obtained from cranberry juice concentrate by Amberlite XAD7HP-column chromatography. The H. pylori growth inhibition was estimated by OD(660) and titration in liquid culture, and by an agar dilution plate method. The shapes of the bacteria were analyzed by scanning electron microscopy.

RESULTS: Cranberry extract suppressed bacterial proliferation in a dose-dependent manner. In the comparison with other juices, polyphenol-rich fruits (cranberries, blueberries, and red grapes) showed similar growth inhibitory activity, whereas polyphenol-poor fruits (oranges, pineapples, apples, and white grapes) did not show any activity. The polyphenol-rich fraction of cranberry maintained the H. pylori-growth inhibitory activity. More bacteria in a coccoid form were observed after culture with cranberry.

CONCLUSION: Cranberry extract inhibited H. pylori proliferation and it is suggested that polyphenols are responsible for this action. The morphological analysis suggested that cranberry induces H. pylori to develop a coccoid form, thereby inhibiting its growth bacteriostatically. Further basic studies to clarify these mechanisms in combination with in vivo studies are needed.