Inhibitory effect of a high-molecular-weight constituent of cranberry on adhesion of oral bacteria

Antibiotic versus cranberry in the treatment of uncomplicated urinary infection: a randomized controlled trial

OBJECTIVE

This study was designed to determine the effect of cranberry extract used in patients with single urinary tract infections.

METHODS

Patients with simple-type urinary tract infections were divided into two groups. Treatment with fosfomycin or cranberry tablet was started. On days 1, 3, and 7 of the treatment, whether there was a decrease in the complaints was evaluated with a Likert-type scale. The recovery status of urinary tract infections and the well-being of patients were compared via antibiotic and cranberry groups.

RESULTS

After the treatment, the leukocyte levels of the cranberry users were at the same level as those of the other group, and the rate of well-being and the portion of patients that reported to be "very well" on days 3 and 7 in the cranberry group was significantly higher compared with the fosfomycin group (p<0.05).

CONCLUSION

Considering the results of this study, it was determined that the patient's complaints decreased from day 3 and their well-being increased with the use of cranberry only. Specifically, on day 7, the well-being of the cranberry group was higher than that of the fosfomycin group. For this reason, cranberry is a favorable alternative to antibiotics in uncomplicated and simple urinary tract infections.

Comparative clinical evaluation of a local drug delivery of cranberry and garcinia fruit gel with tetracycline fibers for amelioration of periodontitis: A split mouth study

Background

The present study formulates and evaluates a polyberry gel comprising extracts of cranberry (Vaccinium macrocarpon) and brindle berry (Garcinia cambogia) in patients suffering from chronic periodontitis.

Materials and Methods

The polyberry gel was evaluated for various physicochemical parameters, in vitro permeability and stability, and the active phytoconstituents were quantified by High-performance thin layer chromatography (HPTLC). Total phenolic content, total antioxidants, and ascorbic acid were estimated in the two extracts by in vitro assays. Patients suffering from chronic periodontitis with probing pocket depth (PPD) up to 5 mm were divided into 3 groups of 21 patients each and treated with scaling and root planing (SRP) or SRP followed by subgingival placement of polyberry gel or tetracycline fibers (standard). Plaque Index (PI), Gingival Index (GI), PPD, Clinical Attachment Level (CAL), and the salivary aspartate aminotransferase (AST) and C-reactive protein (CRP) levels were recorded at baseline and after 1 month.

Results

A significant (P < 0.01) reduction in the periodontic disease parameters was observed in the standard and gel-treated groups between their baseline and 1-month time-interval readings. The polyberry gel treatment significantly (P < 0.05 for AST and P < 0.01 for the rest) attenuated the periodontitis-elevated PI, GI PPD, CAL, AST and CRP levels when compared with SRP at the end of the study and was comparable with tetracycline.

Conclusion

The amelioration of periodontitis and gingival inflammation may be attributed to the potent antioxidant activity of the polyphenolic phytoconstituents of the gel. The polyberry gel may thus be used as a safe adjunct to SRP/tetracycline in chronic periodontitis.

The effect of cranberry juice and a cranberry functional beverage on the growth and metabolic activity of selected oral bacteria

BACKGROUND

The oral microbiota is a significant risk indicator for oral diseases, such as dental caries and periodontal inflammation. Much attention is presently paid to the development of functional foods (e.g. beverages containing cranberry constituents, or foods containing probiotics) that may serve as adjuncts for oral disease treatments (e.g. periodontitis and caries). Cranberry fruit, due to its unique chemical composition and antimicrobial potential, is a possible ingredient of such foods. The study aimed to investigate the effects of cranberry juice (CJ) and a cranberry functional beverage (mixture of 80% v/v apple juice, 20% v/v cranberry juice, and 0.25 g/100 mL ground cinnamon; CFB) on the growth and metabolic activity of selected oral bacteria.

METHODS

Serial dilution pour plate method (SDPP) was used to examine the effect of CJ and CFB on the growth of Actinomyces naeslundii, Streptococcus mutans, and Lactobacillus paracasei subsp. paracasei. 48-h electrical impedance measurements (EIM) during the cultivation of A. naeslundii were applied to evaluate the utility of the method as a rapid alternative for the assessment of the antimicrobial potential of cranberry beverages.

RESULTS

The tested bacteria differed in their susceptibility to the antimicrobial action of CJ and CFB, with L. paracasei subsp. paracasei being least vulnerable to CFB (according to SDPP). Although CJ at a concentration of 0.5 mL/mL, showed a bactericidal effect on the growth of S. mutans, A. naeslundii was more sensitive to CJ (SDPP). Its inhibitory effect on A. naeslundii was seen even at concentrations as small as 0.03125-0.125 mL/mL (SDPP and EIM). On the other hand, S. mutans seemed to be more vulnerable to CFB than A. naeslundii (SDPP).

CONCLUSIONS

CFB may be considered an adjunct in the treatment of oral diseases due to its action against selected oral pathogens, and not against the presumably beneficial L. paracasei subsp. paracasei. Bioelectrical impedance measurements appear to be a quick alternative to evaluating the antimicrobial activity of fruit beverages, but their utility should be confirmed with tests on other bacteria.

Antimicrobial Effect of Natural Berry Juices on Common Oral Pathogenic Bacteria

(1) Background: Antimicrobial agents such as chlorhexidine (CHX) are commonly used in oral plaque control. However, sometimes those agents lack antimicrobial efficiency or cause undesired side effects. To identify alternative anti-infective agents, the present study investigated the antibacterial activity of all-fruit juices derived from blackcurrant, redcurrant, cranberry and raspberry on common oral pathogenic gram-positive and gram-negative bacteria (Streptococcus mutans, Streptococcus gordonii, Streptococcus sobrinus, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Enterococcus faecalis). (2) Methods: Antibacterial efficiency was evaluated by agar diffusion assay and in direct contact with bacteria in planktonic culture. Furthermore, cytotoxicity on human gingival fibroblasts was determined. (3) Results: Blackcurrant juice was most efficient at suppressing bacteria; followed by the activity of redcurrant and cranberry juice. Raspberry juice only suppressed P. gingivalis significantly. Only high-concentrated blackcurrant juice showed minimal cytotoxic effects which were significantly less compared to the action of CHX. (4) Conclusion: Extracts from natural berry juices might be used for safe and efficient suppression of oral pathogenic bacterial species.

Cranberry extract-based formulations for preventing bacterial biofilms

Generating formulations for the delivery of a mixture of natural compounds extracted from natural sources is a challenge because of unknown active and inactive ingredients and possible interactions between them. As one example, natural cranberry extracts have been proposed for the prevention of biofilm formation on dental pellicle or teeth. However, such extracts may contain phenolic acids, flavonol glycosides along with other constituents like coumaroyl iridoid glycosides, flavonoids, alpha-linolenic acid, n-6 (or n-3) fatty acids, and crude fiber. Due to the presence of a variety of compounds, determining which molecules (and how many molecules) are essential for preventing biofilm growth is nontrivial to ascertain. Therefore, a formulation that could contain natural, unrefined, cranberry extract (with all its constituent compounds) at high loading would be ideal. Accordingly, we have generated several candidate formulations including poly(lactic-co-glycolic) acid (PLGA)-based microencapsulation of cranberry extract (CE15) as well as formulations including stearic acid along with polyvinylpyrrolidone (PVP) or Ethyl lauroyl arginate (LAE) complexed with cranberry extracts (CE15). We found that stearic acid in combination with PVP or LAE as excipients led to higher loading of the active and inactive compounds in CE15 as compared with a PLGA microencapsulation and also sustained release of CE15 in a tunable manner. Using this method, we have been able to generate two successful formulations (one preventative based, one treatment based) that effectively inhibit biofilm growth when incubated with saliva. In addition to cranberry extract, this technique could also be a promising candidate for other natural extracts to form controlled release systems.Graphical abstract.

Molecular Mechanisms That Define Redox Balance Function in Pathogen-Host Interactions-Is There a Role for Dietary Bioactive Polyphenols?

To ensure a functional immune system, the mammalian host must detect and respond to the presence of pathogenic bacteria during infection. This is accomplished in part by generating reactive oxygen species (ROS) that target invading bacteria; a process that is facilitated by NADPH oxidase upregulation. Thus, bacterial pathogens must overcome the oxidative burst produced by the host innate immune cells in order to survive and proliferate. In this way, pathogenic bacteria develop virulence, which is related to the affinity to secrete effector proteins against host ROS in order to facilitate microbial survival in the host cell. These effectors scavenge the host generated ROS directly, or alternatively, manipulate host cell signaling mechanisms designed to benefit pathogen survival. The redox-balance of the host is important for the regulation of cell signaling activities that include mitogen-activated protein kinase (MAPK), p21-activated kinase (PAK), phosphatidylinositol 3-kinase (PI3K)/Akt, and nuclear factor κB (NF-κB) pathways. An understanding of the function of pathogenic effectors to divert host cell signaling is important to ascertain the mechanisms underlying pathogen virulence and the eventual host–pathogen relationship. Herein, we examine the effectors produced by the microbial secretion system, placing emphasis on how they target molecular signaling mechanisms involved in a host immune response. Moreover, we discuss the potential impact of bioactive polyphenols in modulating these molecular interactions that will ultimately influence pathogen virulence.

Antioxidant properties and structured biodiversity in a diverse set of wild cranberry clones

Wild germplasm with elevated antioxidants are a useful resource for using directly and in a breeding program. In a study with 136 wild clones and two cranberry cultivars, phenolic, flavonoid and anthocyanin contents varied 2.79, 2.70 and 17.46 times, respectively. The antioxidant activity ranged from 1.17 ± 0.01 to 2.53 ± 0.05 mg/g and varied 2.16 times. Seventy-five of wild clones and the cultivar Franklin were grouped into five distinct classes by molecular structure analysis using inter simple sequence repeat (ISSR), expressed sequence tag-simple sequence repeat (EST-SSR) and EST-polymerase chain reaction (PCR) markers. Grouping with DNA markers did not coincide with that of based on antioxidant properties. Present study indicates that genetic diversity analysis combined with antioxidant properties of wild germplasm play a significant role for conservation and in selecting diverse genotypes for future berry crop improvement.

The Gastrointestinal Tract as a Key Target Organ for the Health-Promoting Effects of Dietary Proanthocyanidins

Proanthocyanidins (PACs) are polymers of flavan-3-ols abundant in many vegetable foods and beverages widely consumed in the human diet. There is increasing evidence supporting the beneficial impact of dietary PACs in the prevention and nutritional management of non-communicable chronic diseases. It is considered that PACs with a degree of polymerization >3 remain unabsorbed in the gastrointestinal (GI) tract and accumulate in the colonic lumen. Accordingly, the GI tract may be considered as a key organ for the healthy-promoting effects of dietary PACs. PACs form non-specific complexes with salivary proteins in mouth, originating the sensation of astringency, and with dietary proteins, pancreatic enzymes, and nutrient transporters in the intestinal lumen, decreasing the digestion and absorption of carbohydrates, proteins, and lipids. They also exert antimicrobial activities, interfering with cariogenic or ulcerogenic pathogens in the mouth (Streptococcus mutans) and stomach (Helicobacter pylori), respectively. Through their antioxidant and antiinflammatory properties, PACs decrease inflammatory processes in animal model of gastric and colonic inflammation. Interestingly, they exert prebiotic activities, stimulating the growth of Lactobacillus spp. and Bifidobacterium spp. as well as some butyrate-producing bacteria in the colon. Finally, PACs are also metabolized by the gut microbiota, producing metabolites, mainly aromatic acids and valerolactones, which accumulate in the colon and/or are absorbed into the bloodstream. Accordingly, these compounds could display biological activities on the colonic epithelium or in extra-intestinal tissues and, therefore, contribute to part of the beneficial effects of dietary PACs.

Black Currant (Ribes nigrum L.) and Bilberry (Vaccinium myrtillus L.) Fruit Juices Inhibit Adhesion of Asaia spp

The aim of the study was to evaluate the activity of high-polyphenolic black currant (Ribes nigrum L.) and bilberry (Vaccinium myrtillus L.) juices against bacterial strains Asaia lannensis and Asaia bogorensis isolated as spoilage of commercial soft drinks. The composition of fruit juices was evaluated using chromatographic techniques HPLC and LC-MS. The adhesion to glass, polystyrene, and polyethylene terephthalate in two different culture media was evaluated by luminometry and the plate count method. The major anthocyanins in the V. myrtillus were petunidin-3-glucoside, malvidin-3-glucoside, cyanidin-3-glucoside, and delphinidin-3-glucoside, while in R. nigrum delphinidin-3-rutinoside and cyanidin-3-rutinoside were detected. The LC-MS analysis showed presence of anthocyanins (delphinidin, cyanidin, petunidin, and malvidin derivatives), phenolic acids (chlorogenic and neochlorogenic acids), flavonols (quercetin-3-glucoside, quercetin-3-rutinoside), and flavanols (procyanidin B2 and procyanidin type A2). Additionally, in the bilberry juice A type procyanidin trimer was detected. The adhesion of Asaia spp. cells depended on the type of medium, carbon sources, and the type of abiotic surfaces. We noted that the adhesion was significantly stronger in minimal medium containing sucrose. The addition of bilberry and black currant juices notably reduced bacterial growth as well as cell adhesion to polyethylene terephthalate surfaces.

Inhibitory effect of cranberry extract on periodontopathogenic biofilm: An integrative review

Background:

Combating biofilm-dependent oral infections involves the use of synthetic antibiotics, which are often associated with bacterial resistance and adverse effects. As a result, herbs such as cranberry have emerged as an alternative treatment. The aim of this study was to evaluate, through an integrative literature review, the effectiveness of cranberry extract on cultures and biofilms of periodontopathogenic bacteria.

Materials and Methods:

In vitro and in vivo studies evaluating the action of cranberry extract on the growth, coaggregation and formation of periodontopathogenic bacteria and periodontal biofilm were identified. Searches were carried out in the “Cochrane Library,” “MEDLINE,” “Web of Science,” “Scopus,” “LILACS,” “Scielo,” and “Google Scholar” databases, using the terms: “vaccinium macrocarpon;” “cranberries;” “cranberry;” “biofilms;” “periodontitis;” “chronic periodontitis;” “aggressive periodontitis;” “periodontal diseases;” and “periodont*.”

Results:

a low number of studies evaluating the effectiveness of cranberry extract on periodontal disease were found, and no human studies were identified. In general, the eight studies included in the revision found that the compounds effectively inhibited the formation of a biofilm of Porphyromonas gingivalis and Fusobacterium nucleatum at concentrations equal or superior to 62.5 μg/ml, but did not significantly inhibit bacterial growth or promote the breakdown of preformed biofilm.

Conclusions:

while most of the studies presented certain methodological limitations, they did identify an inhibiting effect of cranberry on periodontal bacteria. These results serve as support for the development of further studies evaluating the most effective vehicle and ideal concentration that can be used without causing adverse effects on oral tissues.

High-Molecular-Weight Proanthocyanidins in Foods: Overcoming Analytical Challenges in Pursuit of Novel Dietary Bioactive Components

Proanthocyanidins (PACs) are an abundant but complex class of polyphenols found in foods and botanicals. PACs are polymeric flavanols with a variety of linkages and subunits. Connectivity and degree of polymerization (DP) determine PAC bioavailability and bioactivity. Current quantitative and qualitative methods may ignore a large percentage of dietary PACs. Subsequent correlations between intake and activity are hindered by a lack of understanding of the true PAC complexity in many foods. Additionally, estimates of dietary intakes are likely inaccurate, as nutrient databank values are largely based on standards from cocoa (monomers to decamers) and blueberries (mean DP of 36). Improved analytical methodologies are needed to increase our understanding of the biological roles of these complex compounds.

Adhesion of Asaia bogorensis to Glass and Polystyrene in the Presence of Cranberry Juice

The aim of the study was to evaluate the adhesion abilities of the acetic acid bacterium Asaia bogorensis to glass and polystyrene in the presence of American cranberry (Vaccinium macrocarpon) juice. The strain of A. bogorensis used was isolated from spoiled commercial fruit-flavored drinking water. The cranberry juice was analyzed for polyphenols, organic acids, and carbohydrates using high-performance liquid chromatography and liquid chromatography-mass spectrometry techniques. The adhesive abilities of bacterial cells in culture medium supplemented with cranberry juice were determined using luminometry and microscopy. The viability of adhered and planktonic bacterial cells was determined by the plate count method, and the relative adhesion coefficient was calculated. This strain of A. bogorensis was characterized by strong adhesion properties that were dependent upon the type of surface. The highest level of cell adhesion was found on the polystyrene. However, in the presence of 10% cranberry juice, attachment of bacterial cells was three times lower. Chemical analysis of juice revealed the presence of sugars, organic acids, and anthocyanins, which were identified as galactosides, glucosides, and arabinosides of cyanidin and peonidin. A-type proanthocyanidins responsible for the antiadhesion properties of V. macrocarpon also were detected.

Surfaces for competitive selective bacterial capture from protein solutions

Active surfaces that form the basis for bacterial sensors for threat detection, food safety, or certain diagnostic applications rely on bacterial adhesion. However, bacteria capture from complex fluids on the active surfaces can be reduced by the competing adsorption of proteins and other large molecules. Such adsorption can also interfere with device performance. As a result, multiple upstream processing steps are frequently employed to separate macromolecules from any cells, which remain in the buffer. Here, we present an economical approach to capture bacteria, without competitive adsorption by proteins, on engineered surfaces that do not employ biomolecular recognition, antibodies, or other molecules with engineered sequences. The surfaces are based on polyethylene glycol (PEG) brushes that, on their own, repel both proteins and bacteria. These PEG brushes backfill the surface around sparsely adsorbed cationic polymer coils (here, poly-L-lysine (PLL)). The PLL coils are effectively embedded within the brush and produce locally cationic nanoscale regions that attract negatively charged regions of proteins or cells against the steric background repulsion from the PEG brush. By carefully designing the surfaces to include just enough PLL to capture bacteria, but not enough to capture proteins, we achieve sharp selectivity where S. aureus is captured from albumin- or fibrinogen-containing solutions, but free albumin or fibrinogen molecules are rejected from the surface. Bacterial adhesion on these surfaces is not reduced by competitive protein adsorption, in contrast to performance of more uniformly cationic surfaces. Also, protein adsorption to the bacteria does not interfere with capture, at least for the case of S. aureus, to which fibrinogen binds through a specific receptor.

Effects of cranberry components on human aggressive periodontitis gingival fibroblasts

BACKGROUND AND OBJECTIVE

Aggressive periodontitis (AgP) causes rapid periodontal breakdown involving AgP gingival fibroblast production of cytokines [i.e. interleukin (IL)-6, a bone metabolism regulator], and matrix metalloproteinase (MMP)-3. Lipopolysaccharide upregulates fibroblast IL-6 and MMP-3, via transcription factors (i.e. NF-κB). Cranberry (Vaccinium macrocarpon) inhibits lipopolysaccharide-stimulated macrophage and normal gingival fibroblast activities, but little is known of its effects on AgP fibroblasts. Objectives of this study are to use AgP fibroblasts, to determine cytotoxicity of cranberry components or periodontopathogen (Fusobacterium nucleatum, Porphyromonas gingivalis) lipopolysaccharide ± cranberry components, and effects of cranberry components on lipopolysaccharide-stimulated NF-κB activation and IL-6 and MMP-3 production.

MATERIAL AND METHODS

AgP fibroblasts were incubated ≤ 6 d with high molecular weight non-dialyzable material (NDM) (derived from cranberry juice (1-500 μg/mL) or lipopolysaccharide (1 μg/mL) ± NDM. Membrane damage and viability were assessed by enzyme activity released into cell supernatants and activity of a mitochondrial enzyme, respectively. Secreted IL-6 and MMP-3 were measured by ELISA. NF-κB p65 was measured via binding to an oligonucleotide containing the NF-κB consensus site. Data were analyzed using analysis of variance and Scheffe's F procedure for post hoc comparisons.

RESULTS

Short-term exposure to NDM, or lipopolysaccharide ± NDM caused no membrane damage. NDM (≤ 100 μg/mL) or lipopolysaccharide ± NDM had no effect on viability ≤ 7 d exposure. NDM (50 μg/mL) inhibited lipopolysaccharide-stimulated p65 (P ≤ 0.003) and constitutive or lipopolysaccharide-stimulated MMP-3 (P ≤ 0.02). NDM increased AgP fibroblast constitutive or lipopolysaccharide-stimulated IL-6 (P ≤ 0.0001), but inhibited normal human gingival fibroblast IL-6 (P ≤ 0.01).

CONCLUSION

Lack of toxicity of low NDM concentrations, and its inhibition of NF-κB and MMP-3, suggest that cranberry components may regulate AgP fibroblast inflammatory responses. Distinct effects of NDM on AgP and gingival fibroblast production of IL-6 (which can have both positive and negative effects on bone metabolism) may reflect phenotypic differences in IL-6 regulation in the two cell types.

Inhibition of Streptococcus gordonii metabolic activity in biofilm by cranberry juice high-molecular-weight component

Previous studies demonstrated that a cranberry high-molecular-mass, nondialyzable material (NDM) can inhibit adhesion of numerous species of bacteria and prevents bacterial coaggregation of bacterial pairs. Bacterial coaggregation leads to plaque formation leading to biofilm development on surfaces of oral cavity. In the present study, we evaluated the effect of low concentrations of NDM on Streptococcus gordonii metabolic activity and biofilm formation on restorative dental surfaces. We found that the NDM selectively inhibited metabolic activity of S. gordonii, without affecting bacterial viability. Inhibiting the metabolic activity of bacteria in biofilm may benefit the health of the oral cavity.

Food components with anticaries activity

Caries is the most common oral infectious disease in the world. Its development is influenced also by diet components that interfere with pathogen mutans group Streptococci (MGS) activity. A very active research to identify functional foods and their components that are generally recognised as safe has been ongoing, with the aim of developing alternative approaches, to the use of synthetic chlorhexidine, and at the reduction or prevention of caries. Until now convincing evidence exists only for green tea as a functional food for oral health, partly owing to its high content of catechins, especially epigallocatechin-gallate. A number of other foods showed potential anticaries activity. Some other foods able to act against MGS growth and/or their virulence factors in in vitro tests are: apple, red grape seeds, red wine (proanthocyanidins), nutmeg (macelignan), ajowan caraway (nafthalen-derivative), coffee (trigonelline, nicotinic and chlorogenic acids, melanoidins), barley coffee (melanoidins), chicory and mushroom (quinic acid). In vivo anticaries activity has been shown by cranberry (procyanidins), glycyrrhiza root (glycyrrhizol-A), myrtus ethanolic extract, garlic aqueous extract, cocoa extracts (procyanidins), and propolis (apigenin, tt-farnesol).

Antiaggregation potential of berry fractions against pairs of Streptococcus mutans with Fusobacterium nucleatum or Actinomyces naeslundii

Coaggregation is an interspecies adhesion process, which is essential to the development of dental plaque. This is an in vitro study of the composition of the soluble solids in the berry juice molecular size fractions (<10 kDa, FI; 10-100 kDa, FII; >100 kDa, FIII) derived from apple, bilberry, blackcurrant, cloudberry, crowberry and lingonberry and their ability to inhibit and reverse coaggregation of the pairs of common species in dental plaque: Streptococcus mutans with Fusobacterium nucleatum or Actinomyces naeslundii. Inhibitory and reversal activity was found in the molecular size fractions FII and FIII of bilberry, blackcurrant, crowberry and lingonberry. The active fractions contained higher amounts of polyphenols (5-12% of soluble solids) than those without activity (<2% of soluble solids). Proanthocyanidins dominated in the active lingonberry juice fractions FII and FIII and also small amounts of anthocyanins were detected. Anthocyanins, proanthocyanidins and flavonol glycosides were prevalent in FII and FIII fractions of bilberry, blackcurrant and crowberry juices. Comparable amounts of sugars and titratable acids were present in the latter three berry juice fractions of different size. The results indicate that the high molecular size fractions of lingonberry, bilberry, blackcurrant and crowberry juices have antiaggregation potential on common oral bacteria, the potential being associated with their polyphenolic content.

Inhibition activity of wild berry juice fractions against Streptococcus pneumoniae binding to human bronchial cells

Bacterial adhesion to the cell surface is a crucial step before infection can take place. Inhibition of bacterial binding offers a novel preventive approach against infections. Cranberry (Vaccinium macrocarpon Ait.) juice has been found to have antiadhesive activity against different bacteria. Streptococcus pneumoniae is an important pathogen and the most common cause for pneumonia, meningitis, and otitis media. In this study the inhibitory activity of cranberry (Vaccinium oxycoccos L.), bilberry (Vaccinium myrtillus L.) and crowberry (Empetrum nigrum and Empetrum hermaphroditum L.) juice fractions against pneumococcal binding was tested using human bronchial cells (Calu-3) as an adhesion model. In addition, the antimicrobial activity of the berry juice fractions was tested. It was found that the studied berry juice fractions had antiadhesion activity and cranberry juice was the most active. The adhesion inhibition activity of cranberry juice was nearly 90% at a concentration of 8.7 mg/g of soluble solids. The antimicrobial activity of the studied berry juice fractions was found to be remarkable; pneumococcal growth was inhibited totally at a concentration of ∼86 mg/g. Both antiadhesion and antimicrobial activities were reduced after solid-phase extraction of the berry juices, which may suggest molecular synergistic effects of the berry juice molecules against S. pneumoniae. The findings indicate that cranberry, bilberry and crowberry juices have potential against pneumococcal infections.

Iron chelation by cranberry juice and its impact on Escherichia coli growth

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.

Evaluation of an aqueous-ethanolic extract from Pelargonium sidoides (EPs® 7630) for its activity against group A-streptococci adhesion to human HEp-2 epithelial cells

AIM OF THE STUDY

The root extract of Pelargonium sidoides DC (Geraniaceae), EPs® 7630, is currently used to treat respiratory tract infections. The therapeutic benefits are largely related to the modulation of the non-specific immune system. The present study was designed to investigate the anti-adhesive activity of this herbal medicine with Streptococcus pyogenes as model microorganism and to identify the underlying biologically active principle.

MATERIALS AND METHODS

Adherence of fluorescent-labelled group A-streptococci (GAS) to human epithelial (HEp-2) cells was assessed by flow cytometry. Anti-adhesive properties of the parent extract as well as a methanol-soluble (MSF) and a methanol-insoluble fraction (MIF) derived thereof were examined. Treatment with skin powder produced polyphenol-free samples which were included for comparison. Anti-adherence studies were extended to a series of highly purified proanthocyanidins including homogenous epicatechin- and catechin-based polyflavans, a 'mixed' procyanidin sample, an A-type proanthocyanidin mixture as well as a prodelphinidin test substance.

RESULTS

After pre-treatment of GAS with EPs® 7630 or its subfractions MIF and MSF at concentrations of 30 μg/ml, adhesion of the pathogen to HEp-2 cells was inhibited by ca. 45%, ca. 35% and ca. 30%, respectively. However, following preincubation of cells with the extract and the fractions no effect was observed. This finding indicates that the anti-adhesive effects are due to interactions with binding factors on the bacterial surface. Since polyphenol-free samples proved to be inactive, proanthocyanidins appear to represent the anti-adhesive principle. Comparative studies with chemically defined proanthocyanidins revealed that the prodelphinidin nature, i.e. the pyrogallol B-ring elements of constituent flavanyl units, represented an important structural feature of the anti-adhesive potential of this herbal medicine.

CONCLUSIONS

The current data provide strong evidence for a potent anti-adhesion principle of the Pelargonium sidoides root extract related to specific proanthocyanidins. This finding suggests an interaction with bacterial binding sites in a specific rather than non-specific manner. However, the blocked adhesion molecules remain to be identified. The anti-adhesive mechanism may well contribute to the anti-infective activity of EPs® 7630 at an early time point of a bacterial infection.

Bioactive compounds in cranberries and their biological properties

Cranberries are healthy fruit that contribute color, flavor, nutritional value, and functionality. They are one of only three fruits native to America. Over the past decade, public interest for the North American cranberry (Vaccinium macrocarpon) has been rising with reports of their potential health benefits linked to the numerous phytochemicals present in the fruit--the anthocyanins, the flavonols, the flavan-3-ols, the proanthocyanidins, and the phenolic acid derivatives. The presence of these phytochemicals appears to be responsible for the cranberry property of preventing many diseases and infections, including cardiovascular diseases, various cancers, and infections involving the urinary tract, dental health, and Helicobacter pylori-induced stomach ulcers and cancers. Recent years have seen important breakthroughs in our understanding of the mechanisms through which these compounds exert their beneficial biological effects, yet these remain to be scientifically substantiated. In this paper these characteristics, as well as the antioxidant, radical scavenging, antibacterial, antimutagen, and anticarcinogen properties of cranberry major bioactive compounds are explained.

Phytochemicals of cranberries and cranberry products: characterization, potential health effects, and processing stability

Emerging evidence is elucidating how non-nutrient phytochemicals underlie the health promotion afforded by fruits and vegetables. This review focuses on Vaccinium macrocarpon, the American cranberry, compiling a comprehensive list of its known phytochemical components, and detailing their prevalence in cranberry fruit and its products. Flavonoids, especially colored anthocyanins, abundant flavonols, and unique proanthocyanidins, have attracted major research attention. Other notable active components include phenolic acids, benzoates, hydroxycinnamic acids, terpenes and organic acids. Health effects of cranberries, cranberry products, and isolated cranberry components in humans and animals, as well as in vitro, are debated. Evidence for protection from several bacterial pathogens, cancer, cardiovascular disease, and inflammation is compelling, while neuroprotection and anti-viral activity also have begun to draw new consideration. Emerging bioavailability data is considered and potential molecular mechanisms are evaluated, linking phytochemicals to health effects through their biochemical properties and reactions. Finally, the effects of processing and storage on cranberry phytochemicals is discussed, with a focus on identifying research gaps and novel means to preserve their natural, health-promoting components.

Influence of cranberry proanthocyanidins on formation of biofilms by Streptococcus mutans on saliva-coated apatitic surface and on dental caries development in vivo

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.

Cranberry and urinary tract infections

Urinary tract infection (UTI) refers to the presence of clinical signs and symptoms arising from the genitourinary tract plus the presence of one or more micro-organisms in the urine exceeding a threshold value for significance (ranges from 102 to 103 colony-forming units/mL). Infections are localized to the bladder (cystitis), renal parenchyma (pyelonephritis) or prostate (acute or chronic bacterial prostatitis). Single UTI episodes are very common, especially in adult women where there is a 50-fold predominance compared with adult men. In addition, recurrent UTIs are also common, occurring in up to one-third of women after first-episode UTIs. Recurrences requiring intervention are usually defined as two or more episodes over 6 months or three or more episodes over 1 year (this definition applies only to young women with acute uncomplicated UTIs). A cornerstone of prevention of UTI recurrence has been the use of low-dose once-daily or post-coital antimicrobials; however, much interest has surrounded non-antimicrobial-based approaches undergoing investigation such as use of probiotics, vaccines, oligosaccharide inhibitors of bacterial adherence and colonization, and bacterial interference with immunoreactive extracts of Escherichia coli. Local (intravaginal) estrogen therapy has had mixed results to date. Cranberry products in a variety of formulations have also undergone extensive evaluation over several decades in the management of UTIs. At present, there is no evidence that cranberry can be used to treat UTIs. Hence, the focus has been on its use as a preventative strategy. Cranberry has been effective in vitro and in vivo in animals for the prevention of UTI. Cranberry appears to work by inhibiting the adhesion of type I and P-fimbriated uropathogens (e.g. uropathogenic E. coli) to the uroepithelium, thus impairing colonization and subsequent infection. The isolation of the component(s) of cranberry with this activity has been a daunting task, considering the hundreds of compounds found in the fruit and its juice derivatives. Reasonable evidence suggests that the anthocyanidin/proanthocyanidin moieties are potent antiadhesion compounds. However, problems still exist with standardization of cranberry products, which makes it extremely difficult to compare products or extrapolate results. Unfortunately, most clinical trials have had design deficiencies and none have evaluated specific key cranberry-derived compounds considered likely to be active moieties (e.g. proanthocyanidins). In general, the preventive efficacy of cranberry has been variable and modest at best. Meta-analyses have established that recurrence rates over 1 year are reduced approximately 35% in young to middle-aged women. The efficacy of cranberry in other groups (i.e. elderly, paediatric patients, those with neurogenic bladder, those with chronic indwelling urinary catheters) is questionable. Withdrawal rates have been quite high (up to 55%), suggesting that these products may not be acceptable over long periods. Adverse events include gastrointestinal intolerance, weight gain (due to the excessive calorie load) and drug-cranberry interactions (due to the inhibitory effect of flavonoids on cytochrome P450-mediated drug metabolism). The findings of the Cochrane Collaboration support the potential use of cranberry products in the prophylaxis of recurrent UTIs in young and middle-aged women. However, in light of the heterogeneity of clinical study designs and the lack of consensus regarding the dosage regimen and formulation to use, cranberry products cannot be recommended for the prophylaxis of recurrent UTIs at this time.

Cranberries (Vaccinium macrocarpon) and cardiovascular disease risk factors

The American cranberry (Vaccinium macrocarpon) is one of the three commercially important fruits native to North America. Cranberries are a particularly rich source of phenolic phytochemicals, including phenolic acids (benzoic, hydroxycinnamic, and ellagic acids) and flavonoids (anthocyanins, flavonols, and flavan-3-ols). A growing body of evidence suggests that polyphenols, including those found in cranberries, may contribute to reducing the risk of cardiovascular disease (CVD) by increasing the resistance of LDL to oxidation, inhibiting platelet aggregation, reducing blood pressure, and via other anti-thrombotic and anti-inflammatory mechanisms. Research regarding the bioactivity of cranberries and their constituents on risk factors for CVD is reviewed.

Inhibitory effect of cranberry polyphenol on biofilm formation and cysteine proteases of Porphyromonas gingivalis

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.

Adherence, anti-adherence, and oligosaccharides preventing pathogens from sticking to the host

For many pathogenic bacteria, infections are initiated only after the organism has first adhered to the host cell surface. If adherence can be inhibited, then the subsequent infection can also be inhibited. This approach forms the basis of anti-adherence strategies, which have been devised to prevent a variety of bacterial infections. In this chapter, the molecular basis by which respiratory, urinary, and gastrointestinal tract pathogens adhere to host cells will be described. The five general types of anti-adherence agents will also be reviewed. The most well-studied are the receptor analogs, which include oligosaccharides produced synthetically or derived from natural sources, including milk, berries, and other plants. Their ability to inhibit pathogen adherence may lead to development of novel, food-grade anti-infective agents that are inexpensive and safe.

The cranberry and the urinary tract

Cranberry products have been heralded as natural treatments for urinary tract infections (UTIs) and have been widely used for this purpose. Current evidence favours an antibacterial role for the cranberry's natural polyphenols or tannins. Although limited species- and strain-specific direct inhibition has been determined in vitro, it has been suggested that a key mechanism of inhibition, especially for the abundant uropathogenic E. coli, relies on anti-adhesion properties. Many studies of prevention have been complicated due to the enrollment of patients who have had complicated urinary tracts, and outcomes have not been consistently favourable. In contrast, significant prevention has been shown for acute cystitis among high-risk young females. While reasonably well tolerated and deplete from side effects, further scientific work is required to better place the role of cranberry products in the management of UTIs. Progress in this area has set the stage for further hypothesis testing studies.

Effect of cranberry juice on eradication of Helicobacter pylori in patients treated with antibiotics and a proton pump inhibitor

Cranberry constituents are known to exert anti-adhesion activity on H. pylori in vitro. To determine their possible additive effect to triple therapy with omeprazole, amoxicillin and clarithromycin (OAC), a double-blind randomized clinical study was carried out. One-hundred-seventy-seven patients with H. pylori infection treated with OAC for 1 week were randomly allocated to receive 250 mL of either cranberry juice (cranberry-OAC, n = 89) or placebo beverage (placebo-OAC, n = 88) twice daily and only cranberry juice or placebo beverage for the next 2 weeks. Treatment outcome was determined with the(13)C urea breath test ((13)C-UBT). An additional control group consisted of patients referred to the same center during the same period who were treated with OAC alone for 1 week (non-placebo-OAC, n = 712). Overall, the rate of H. pylori eradication ((13)C-UBT < 3.5) was 82.5%, with no statistically significant difference among the three arms. Analysis by gender revealed that for female subjects, the eradication rate was higher in the cranberry-OAC arm (n = 42, 95.2%) than in the placebo-OAC arm (n = 53, 86.8%) and significantly higher than in the non-placebo-OAC group (n = 425, 80%; p = 0.03). For males, the rate was nonsignificantly lower in the cranberry-OAC arm (n = 35, 73.9%) than in the placebo-OAC arm (n = 45, 80.0%) and non-placebo-OAC group (n = 287, 85.0%). These results suggest that the addition of cranberry to triple therapy improves the rate of H. pylori eradication in females.

The effect of cocoa polyphenols on the growth, metabolism, and biofilm formation by Streptococcus mutans and Streptococcus sanguinis

The aim of this study was to determine if cocoa polyphenols could interfere with biofilm formation by Streptococcus mutans or Streptococcus sanguinis, and reduce acid production from sucrose by S. mutans. The antimicrobial activity of cocoa polyphenols was assessed against cariogenic (S. mutans) and health-associated (S. sanguinis) species by minimum inhibitory concentration assays. Cocoa polyphenol dimer, tetramer, and pentamer inhibited the growth of S. sanguinis, whereas the growth of S. mutans was unaffected. However, pretreatment of surfaces with cocoa polyphenol pentamer (35 microM) reduced biofilm formation by S. mutans at 4 and 24 h, whereas the effects on S. sanguinis were less consistent. In contrast, brief exposure of preformed biofilms to pentamer either had no significant effect or resulted in increased counts of S. mutans under certain conditions. Cocoa polyphenol pentamer (500 microM) significantly reduced the terminal pH, and inhibited the rate of acid production by S. mutans at pH 7.0. In conclusion, cocoa polyphenols can reduce biofilm formation by S. mutans and S. sanguinis, and inhibit acid production by S. mutans.

Inhibitory effects of cranberry polyphenols on formation and acidogenicity ofStreptococcus mutansbiofilms

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 (P<0.05). 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.

Pathogen reduction in unpasteurized apple cider: adding cranberry juice to enhance the lethality of warm hold and freeze-thaw steps

U.S. Food and Drug Administration (FDA) regulations require processors of apple cider sold wholesale to use processing steps that ensure a 5-log reduction in numbers of the pertinent pathogen, generally considered to be Escherichia coli O157:H7. Current widely used validated pathogen-reduction steps are thermal pasteurization and UV light treatment. These techniques may be unaffordable or undesirable for some processors. This study investigated the cran-cider process, which is the addition of cranberry juice at a 15% (vol/vol) level, followed by warm hold (45 degrees C for 2 h) and freeze-thaw steps (-20 degrees C for 24 h, 5 degrees C for 24 h). When enumeration procedures did not include injury repair, the cran-cider process achieved a > or = 5-log reduction in numbers of E. coli O157:H7, Salmonella serovars, and Listeria monocytogenes. However, an injury-repair step was included in the pathogen enumeration procedure in confirmatory trials, and the resulting E. coli O157:H7 reductions of 3.5 to 4.2 log did not meet the FDA requirement. Consumer evaluation of apple cider subjected to the cran-cider process was favorable with a mean (n = 197) score of 5.8 on a seven-point hedonic scale (where 6 equals "like moderately") and 89% of panelists giving the product a positive score of 5, 6, or 7. The cran-cider process provides a novel way to improve microbial safety of unpasteurized apple cider, but it does not meet FDA-mandated pathogen reductions for wholesalers. However, cider makers selling apple cider only at retail could use the process to improve the safety of their product, provided containers were labeled with the FDA-mandated consumer warning.

Bioactive berry compounds?novel tools against human pathogens

Berry fruits are rich sources of bioactive compounds, such as phenolics and organic acids, which have antimicrobial activities against human pathogens. Among different berries and berry phenolics, cranberry, cloudberry, raspberry, strawberry and bilberry especially possess clear antimicrobial effects against, e.g. Salmonella and Staphylococcus. Complex phenolic polymers, like ellagitannins, are strong antibacterial agents present in cloudberry and raspberry. Several mechanisms of action in the growth inhibition of bacteria are involved, such as destabilisation of cytoplasmic membrane, permeabilisation of plasma membrane, inhibition of extracellular microbial enzymes, direct actions on microbial metabolism and deprivation of the substrates required for microbial growth. Antimicrobial activity of berries may also be related to antiadherence of bacteria to epithelial cells, which is a prerequisite for colonisation and infection of many pathogens. Antimicrobial berry compounds may have important applications in the future as natural antimicrobial agents for food industry as well as for medicine. Some of the novel approaches are discussed.

Effective separation of potent antiproliferation and antiadhesion components from wild blueberry (Vaccinium angustifolium Ait.) fruits

Extracts from wild blueberry (Vaccinium angustifolium Ait.) were separated into proanthocyanidin-rich fractions using liquid vacuum and open column chromatography on Toyopearl and Sephadex LH-20, respectively. Fractions were characterized using analytical tools including mass spectrometry and NMR spectroscopy; fraction composition was correlated with bioactivity using antiproliferation and antiadhesion in vitro assays. There was a significant positive correlation between proanthocyanidin content of different fractions and biological activity in both the antiproliferation and antiadhesion assays. Two fractions containing primarily 4-->8-linked oligomeric proanthocyanidins with average degrees of polymerization (DPn) of 3.25 and 5.65 inhibited adhesion of Escherichia coli responsible for urinary tract infections. Only the fraction with a DPn of 5.65 had significant antiproliferation activity against human prostate and mouse liver cancer cell lines. These findings suggest both antiadhesion and antiproliferation activity are associated with high molecular weight proanthocyanidin oligomers found in wild blueberry fruits.

A high molecular mass cranberry constituent reduces mutans streptococci level in saliva and inhibits in vitro adhesion to hydroxyapatite

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.

Inhibitory effects of cranberry juice on attachment of oral streptococci and biofilm formation

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.

Anti-adhesion therapy of bacterial diseases: prospects and problems

The alarming increase in drug-resistant bacteria makes a search for novel means of fighting bacterial infections imperative. An attractive approach is the use of agents that interfere with the ability of the bacteria to adhere to tissues of the host, since such adhesion is one of the initial stages of the infectious process. The validity of this approach has been unequivocally demonstrated in experiments performed in a wide variety of animals, from mice to monkeys, and recently also in humans. Here we review various approaches to anti-adhesion therapy, including the use of receptor and adhesin analogs, dietary constituents, sublethal concentrations of antibiotics and adhesin-based vaccines. Because anti-adhesive agents are not bactericidal, the propagation and spread of resistant strains is much less likely to occur than as a result of exposure to bactericidal agents, such as antibiotics. Anti-adhesive drugs, once developed, may, therefore, serve as a new means to fight infectious diseases.