Cranberry (Vaccinium macrocarpon) oligosaccharides decrease biofilm formation by uropathogenic Escherichia coli

Gelation and large thermoresponse of cranberry-based xyloglucan

Cranberry waste contains potentially valuable components, such as proanthocyanidins, flavanols, and xyloglucan. Highly-purified xyloglucan (XG) from cranberries were studied through steady and oscillatory shear rheology at various concentrations and temperatures. At room temperature, an apparent yield stress is observed and the storage modulus exceeds the loss modulus ( [Formula: see text] ) for concentrations of 0.5 wt% and higher, indicating that the XG solution has formed a physical hydrogel. Thermoresponsive gelation is observed with a five-order of magnitude increase in shear moduli as it undergoes a weak to strong gel transition around 52 °C. The gelation time was 5 min with an observed storage moduli up to 3500 Pa. Cranberry-based XG exhibits thermoresponsive behavior at concentrations as low as 0.1 wt% (w/v), which is significantly lower than prior gelation studies of XG from other sources. The formation of a weak gel at room temperature and large storage moduli observed at room temperature is likely associated with the low level of impurities and small amount of galactose present in the XG chains.

Short term supplementation with cranberry extract modulates gut microbiota in human and displays a bifidogenic effect

Cranberry is associated with multiple health benefits, which are mostly attributed to its high content of (poly)phenols, particularly flavan-3-ols. However, clinical trials attempting to demonstrate these positive effects have yielded heterogeneous results, partly due to the high inter-individual variability associated with gut microbiota interaction with these molecules. In fact, several studies have demonstrated the ability of these molecules to modulate the gut microbiota in animal and in vitro models, but there is a scarcity of information in human subjects. In addition, it has been recently reported that cranberry also contains high concentrations of oligosaccharides, which could contribute to its bioactivity. Hence, the aim of this study was to fully characterize the (poly)phenolic and oligosaccharidic contents of a commercially available cranberry extract and evaluate its capacity to positively modulate the gut microbiota of 28 human subjects. After only four days, the (poly)phenols and oligosaccharides-rich cranberry extract, induced a strong bifidogenic effect, along with an increase in the abundance of several butyrate-producing bacteria, such as Clostridium and Anaerobutyricum. Plasmatic and fecal short-chain fatty acids profiles were also altered by the cranberry extract with a decrease in acetate ratio and an increase in butyrate ratio. Finally, to characterize the inter-individual variability, we stratified the participants according to the alterations observed in the fecal microbiota following supplementation. Interestingly, individuals having a microbiota characterized by the presence of Prevotella benefited from an increase in Faecalibacterium with the cranberry extract supplementation.

The biosynthesis, degradation, and function of cell wall β-xylosylated xyloglucan mirrors that of arabinoxyloglucan

Xyloglucan is an abundant polysaccharide in many primary cell walls and in the human diet. Decoration of its α-xylosyl sidechains with further sugars is critical for plant growth, even though the sugars themselves vary considerably between species. Plants in the Ericales order - prevalent in human diets - exhibit β1,2-linked xylosyl decorations. The biosynthetic enzymes responsible for adding these xylosyl decorations, as well as the hydrolases that remove them in the human gut, are unidentified. GT47 xyloglucan glycosyltransferase candidates were expressed in Arabidopsis and endo-xyloglucanase products from transgenic wall material were analysed by electrophoresis, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy. The activities of gut bacterial hydrolases BoGH43A and BoGH43B on synthetic glycosides and xyloglucan oligosaccharides were measured by colorimetry and electrophoresis. CcXBT1 is a xyloglucan β-xylosyltransferase from coffee that can modify Arabidopsis xyloglucan and restore the growth of galactosyltransferase mutants. Related VmXST1 is a weakly active xyloglucan α-arabinofuranosyltransferase from cranberry. BoGH43A hydrolyses both α-arabinofuranosylated and β-xylosylated oligosaccharides. CcXBT1's presence in coffee and BoGH43A's promiscuity suggest that β-xylosylated xyloglucan is not only more widespread than thought, but might also nourish beneficial gut bacteria. The evolutionary instability of transferase specificity and lack of hydrolase specificity hint that, to enzymes, xylosides and arabinofuranosides are closely resemblant.

Evidence-based review of nonantibiotic urinary tract infection prevention strategies for women: a patient-centered approach

PURPOSE OF REVIEW

There is a growing interest in nonantibiotic prevention strategies for recurrent urinary tract infections (rUTIs). Our objective is to provide a focused, pragmatic review of the latest evidence.

RECENT FINDINGS

Vaginal estrogen is well tolerated and effective for preventing rUTI in postmenopausal women. Cranberry supplements at sufficient doses are effective in preventing uncomplicated rUTI. Methenamine, d -mannose, and increased hydration all have evidence to support their use, although the evidence is of somewhat variable quality.

SUMMARY

There is sufficient evidence to recommend vaginal estrogen and cranberry as first-line rUTI prevention strategies, particularly in postmenopausal women. Prevention strategies can be used in series or in tandem, based on patient preference and tolerance for side effects, to create effective nonantibiotic rUTI prevention strategies.

Bioactive compounds: a goldmine for defining new strategies against pathogenic bacterial biofilms?

Most human infectious diseases are caused by microorganisms growing as biofilms. These three-dimensional self-organized communities are embedded in a dense matrix allowing microorganisms to persistently inhabit abiotic and biotic surfaces due to increased resistance to both antibiotics and effectors of the immune system. Consequently, there is an urgent need for novel strategies to control biofilm-associated infections. Natural products offer a vast array of chemical structures and possess a wide variety of biological properties; therefore, they have been and continue to be exploited in the search for potential biofilm inhibitors with a specific or multi-locus mechanism of action. This review provides an updated discussion of the major bioactive compounds isolated from several natural sources - such as plants, lichens, algae, microorganisms, animals, and humans - with the potential to inhibit biofilm formation and/or to disperse established biofilms by bacterial pathogens. Despite the very large number of bioactive products, their exact mechanism of action often remains to be clarified and, in some cases, the identity of the active molecule is still unknown. This knowledge gap should be filled thus allowing development of these products not only as novel drugs to combat bacterial biofilms, but also as antibiotic adjuvants to restore the therapeutic efficacy of current antibiotics.

Technological Properties and Composition of Enzymatically Modified Cranberry Pomace

Cranberry pomace obtained after juice production is a good source of dietary fiber and other bioactive compounds. In this study, cranberry pomace was hydrolyzed with Viscozyme® L, Pectinex® Ultra Tropical, Pectinex® Yieldmash Plus, and Celluclast® 1.5L (Novozyme A/S, Denmark). The soluble and insoluble dietary fiber was determined using the Megazyme kit, while the changes in mono-, disaccharide and oligosaccharides’ contents were determined using HPLC-RI; the total phenolic contents were determined by Folin−Ciocalteu’s Assay. Prebiotic activity, using two probiotic strains Lactobacillus acidophilus DSM 20079 and Bifidobacterium animalis DSM 20105, was investigated. The technological properties, such as hydration and oil retention capacity, were evaluated. The enzymatic treatment increased the yield of short-chain soluble saccharides. The highest oligosaccharide content was obtained using Viscozyme® L and Pectinex® Ultra Tropical. All of the tested extracts of cranberry pomace showed the ability to promote growth of selected probiotic bacteria. The insoluble dietary fiber content decreased in all of the samples, while the soluble dietary fiber increased just in samples hydrolyzed with Celluclast® 1.5L. The highest content of total phenolic compounds was obtained using Viscozyme® L and Pectinex® Ultra Tropical (10.9% and 13.1% higher than control, respectively). The enzymatically treated cranberry pomace exhibited lower oil and water retention capacities in most cases. In contrast, water swelling capacity increased by 23% and 70% in samples treated with Viscozyme® L and Celluclast® 1.5L, respectively. Enzymatically treated cranberry pomace has a different composition and technological properties depending on the enzyme used for hydrolysis and can be used in various novel food products.

Cranberry Arabino-Xyloglucan and Pectic Oligosaccharides Induce Lactobacillus Growth and Short-Chain Fatty Acid Production

Numerous health benefits have been reported from the consumption of cranberry-derived products, and recent studies have identified bioactive polysaccharides and oligosaccharides from cranberry pomace. This study aimed to further characterize xyloglucan and pectic oligosaccharide structures from pectinase-treated cranberry pomace and measure the growth and short-chain fatty acid production of 86 Lactobacillus strains using a cranberry oligosaccharide fraction as the carbon source. In addition to arabino-xyloglucan structures, cranberry oligosaccharides included pectic rhamnogalacturonan I which was methyl-esterified, acetylated and contained arabino-galacto-oligosaccharide side chains and a 4,5-unsaturated function at the non-reducing end. When grown on cranberry oligosaccharides, ten Lactobacillus strains reached a final culture density (ΔOD) ≥ 0.50 after 24 h incubation at 32 °C, which was comparable to L. plantarum ATCC BAA 793. All strains produced lactic, acetic, and propionic acids, and all but three strains produced butyric acid. This study demonstrated that the ability to metabolize cranberry oligosaccharides is Lactobacillus strain specific, with some strains having the potential to be probiotics, and for the first time showed these ten strains were capable of growth on this carbon source. The novel cranberry pectic and arabino-xyloglucan oligosaccharide structures reported here combined with the Lactobacillus strains that can metabolize cranberry oligosaccharides and produce short-chain fatty acids, have excellent potential as health-promoting synbiotics.

Clinical Escherichia coli: From Biofilm Formation to New Antibiofilm Strategies

Escherichia coli is one of the species most frequently involved in biofilm-related diseases, being especially important in urinary tract infections, causing relapses or chronic infections. Compared to their planktonic analogues, biofilms confer to the bacteria the capacity to be up to 1000-fold more resistant to antibiotics and to evade the action of the host’s immune system. For this reason, biofilm-related infections are very difficult to treat. To develop new strategies against biofilms, it is important to know the mechanisms involved in their formation. In this review, the different steps of biofilm formation in E. coli, the mechanisms of tolerance to antimicrobials and new compounds and strategies to combat biofilms are discussed.

A Freeze-Dried Cranberry Powder Consistently Enhances SCFA Production and Lowers Abundance of Opportunistic Pathogens In Vitro

The American cranberry, Vaccinium macrocarpon, contains fibers and (poly)phenols that could exert health-promoting effects through modulation of gut microbiota. This study aimed to investigate how a freeze-dried whole cranberry powder (FCP) modulated metabolite production and microbial composition using both a 48-h incubation strategy and a long-term human gut simulator study with the M-SHIME (Mucosal Simulator of the Human Intestinal Microbial Ecosystem). FCP was repeatedly administered over three weeks. The studies included five and three study subjects, respectively. In both models, FCP significantly increased levels of health-related short-chain fatty acids (SCFA: acetate, propionate and butyrate), while decreased levels of branched-chain fatty acids (markers of proteolytic fermentation). Interestingly, FCP consistently increased luminal Bacteroidetes abundances in the proximal colon of the M-SHIME (+17.5 ± 9.3%) at the expense of Proteobacteria (−10.2 ± 1.5%). At family level, this was due to the stimulation of Bacteroidaceae and Prevotellaceae and a decrease of Pseudomonodaceae and Enterobacteriaceae. Despite of interpersonal differences, FCP also increased the abundance of families of known butyrate producers. Overall, FCP displayed an interesting prebiotic potential in vitro given its selective utilization by host microorganisms and potential health-related effects on inhibition of pathogens and selective stimulation of beneficial metabolites.

Cranberry: Chemical Composition, Antioxidant Activity and Impact on Human Health: Overview

Cranberries are a rich source of bioactive compounds that comprise a healthy diet. Cranberry is abundant in nutritional components and many bioactive compounds that have antioxidant properties. Both American (Vaccinium macrocarpon) and European (Vaccinium oxycoccus) cranberry species are rich in polyphenols such as phenolic acids, anthocyanins and flavonoids, and is one of the few fruits that is high in proanthocyanidins, which is linked to many health benefits. The review systematizes information on the chemical composition of cranberry, its antioxidant effect, and the beneficial impact on human health and disease prevention after cranberry consumption, and in particular, its effect against urinary tract inflammation with both adults and children, cardiovascular, oncology diseases, type 2 diabetes, metabolic syndrome, obesity, tooth decay and periodontitis, Helicobacter pylori bacteria in the stomach and other diseases. Additional research needs to study cranberry proteomics profiling, polyphenols interaction and synergism with other biologically active compounds from natural ingredients and what is important in formulation of new functional foods and supplements.

Progress in Alternative Strategies to Combat Antimicrobial Resistance: Focus on Antibiotics

Antibiotic resistance, and, in a broader perspective, antimicrobial resistance (AMR), continues to evolve and spread beyond all boundaries. As a result, infectious diseases have become more challenging or even impossible to treat, leading to an increase in morbidity and mortality. Despite the failure of conventional, traditional antimicrobial therapy, in the past two decades, no novel class of antibiotics has been introduced. Consequently, several novel alternative strategies to combat these (multi-) drug-resistant infectious microorganisms have been identified. The purpose of this review is to gather and consider the strategies that are being applied or proposed as potential alternatives to traditional antibiotics. These strategies include combination therapy, techniques that target the enzymes or proteins responsible for antimicrobial resistance, resistant bacteria, drug delivery systems, physicochemical methods, and unconventional techniques, including the CRISPR-Cas system. These alternative strategies may have the potential to change the treatment of multi-drug-resistant pathogens in human clinical settings.

The Concentration of Organic Acids in Cranberry Juice Modulates the Gut Microbiota in Mice

A daily consumption of cranberry juice (CJ) is linked to many beneficial health effects due to its richness in polyphenols but could also awake some intestinal discomforts due to its organic acid content and possibly lead to intestinal inflammation. Additionally, the impact of such a juice on the gut microbiota is still unknown. Thus, this study aimed to determine the impacts of a daily consumption of CJ and its successive deacidification on the intestinal inflammation and on the gut microbiota in mice. Four deacidified CJs (DCJs) (deacidification rates of 0, 40, 60, and 80%) were produced by electrodialysis with bipolar membrane (EDBM) and administered to C57BL/6J mice for four weeks, while the diet (CHOW) and the water were ad libitum. Different parameters were measured to determine intestinal inflammation when the gut microbiota was profiled. Treatment with a 0% DCJ did not induce intestinal inflammation but increased the gut microbiota diversity and induced a modulation of its functions in comparison with control (water). The effect of the removal of the organic acid content of CJ on the decrease of intestinal inflammation could not be observed. However, deacidification by EDBM of CJ induced an additional increase, in comparison with a 0% DCJ, in the Lachnospiraceae family which have beneficial effects and functions associated with protection of the intestine: the lower the organic acid content, the more bacteria of the Lachnospiraceae family and functions having a positive impact on the gut microbiota.

Enzymatic extraction of pectic oligosaccharides from finger citron (Citrus medica L. var. sarcodactylis Swingle) pomace with antioxidant potential

Finger citron pomace is a cheap and renewable by-product of the citrus processing industry, representing up to 60% of the fruit biomass. In this study, a pectinase-based and ultrasonic-assisted method was firstly used to extract pectic oligosaccharides (POS) from finger citron pomace. Using the orthogonal experiment design (OED), the maximum conversion rate of up to 64.5% from pomace to POS was obtained under the extraction conditions of 0.25 mg mL^-1 pectinase and 50 mg mL^-1 pectin at 45 °C and pH 4.5 for 2 h. The extracted POS was then fractionated and purified to homogeneous oligosaccharides (FCPOS-1) with a molecular weight of 2.15 kDa, and the analyses of monosaccharide composition, FTIR, NMR and ESI-MS indicated that FCPOS-1 consisted of GalA and a small amount of mannose, galactose and arabinose. Multiple antioxidant activity assays in vitro revealed that FCPOS-1 possessed remarkable antioxidant properties, especially scavenging activity against DPPH radicals up to 94.07%. FCPOS-1 has the potential to be an effective natural antioxidant for applications in the food and pharmaceutical industries.

Consumption of cranberry as adjuvant therapy for urinary tract infections in susceptible populations: A systematic review and meta-analysis with trial sequential analysis

The efficacy of cranberry (Vaccinium spp.) as adjuvant therapy in preventing urinary tract infections (UTIs) remains controversial. This study aims to update and determine cranberry effects as adjuvant therapy on the recurrence rate of UTIs in susceptible groups. According to PRISMA guidelines, we conducted a literature search in Web of Science, PubMed, Embase, Scopus, and the Cochrane Library from their inception dates to June 2021. We included articles with data on the incidence of UTIs in susceptible populations using cranberry-containing products. We then conducted a trial sequential analysis to control the risk of type I and type II errors. This meta-analysis included 23 trials with 3979 participants. We found that cranberry-based products intake can significantly reduce the incidence of UTIs in susceptible populations (risk ratio (RR) = 0.70; 95% confidence interval(CI): 0.59 ~ 0.83; P<0.01). We identified a relative risk reduction of 32%, 45% and 51% in women with recurrent UTIs (RR = 0.68; 95% CI: 0.56 ~ 0.81), children (RR = 0.55; 95% CI: 0.31 ~ 0.97) and patients using indwelling catheters (RR = 0.49; 95% CI: 0.33 ~ 0.73). Meanwhile, a relative risk reduction of 35% in people who use cranberry juice compared with those who use cranberry capsule or tablet was observed in the subgroup analysis (RR = 0.65; 95% CI: 0.54 ~ 0.77). The TSA result for the effects of cranberry intake and the decreased risk of UTIs in susceptible groups indicated that the effects were conclusive. In conclusion, our meta-analysis demonstrates that cranberry supplementation significantly reduced the risk of developing UTIs in susceptible populations. Cranberry can be considered as adjuvant therapy for preventing UTIs in susceptible populations. However, given the limitations of the included studies in this meta-analysis, the conclusion should be interpreted with caution.

Highly Active Cranberry's Polyphenolic Fraction: New Advances in Processing and Clinical Applications

Cranberry is a fruit originally from New England and currently growing throughout the east and northeast parts of the USA and Canada. The supplementation of cranberry extracts as nutraceuticals showed to contribute to the prevention of urinary tract infections, and most likely it may help to prevent cardiovascular and gastroenteric diseases, as highlighted by several clinical trials. However, aiming to validate the efficacy and safety of clinical applications as long-term randomized clinical trials (RCTs), further investigations of the mechanisms of action are required. In addition, a real challenge for next years is the standardization of cranberry’s polyphenolic fractions. In this context, the optimization of the extraction process and downstream processing represent a key point for a reliable active principle for the formulation of a food supplement. For this reason, new non-conventional extraction methods have been developed to improve the quality of the extracts and reduce the overall costs. The aim of this survey is to describe both technologies and processes for highly active cranberry extracts as well as the effects observed in clinical studies and the respective tolerability notes.

ANALYSIS OF CARBOHYDRATES AND GLYCOCONJUGATES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION MASS SPECTROMETRY: AN UPDATE FOR 2015-2016

This review is the ninth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2016. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented over 30 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show no sign of deminishing. © 2020 Wiley Periodicals, Inc.

Structural Characterization of Pectic Polysaccharides in the Cell Wall of Stevens Variety Cranberry Using Highly Specific Pectin-Hydrolyzing Enzymes

The potential of poly- and oligosaccharides as functional ingredients depends on the type and glycosidic linkages of their monosaccharide residues, which determine their techno-functional properties, their digestibility and their fermentability. To isolate the pectic polysaccharides of cranberry, alcohol insoluble solids were first obtained from pomace. A sequential extraction with hot phosphate buffer, chelating agents (CH), diluted (DA) and concentrated sodium hydroxide was then carried out. Pectic polysaccharides present in CH and DA extracts were purified by anion exchange and gel filtration chromatography, then sequentially exposed to commercially available pectin-degrading enzymes (endo-polygalacturonase, pectin lyase and endo-arabinanase/endo-galactanase/both). The composition and linkages of the generated fragments revealed important characteristic features, including the presence of homogalacturonan with varied methyl esterification extent, branched type I arabinogalactan and pectic galactan. The presence of arabinan with galactose branches was suggested upon the analysis of the fragments by LC-MS.

A rapid and simple measurement method for biofilm formation inhibitory activity using 96-pin microtiter plate lids

The purpose of this study was to develop a rapid and simple measurement method for biofilm formation inhibitory activity, and to screen food additives and foodstuffs that inhibit biofilm formation. The measurement method for biofilm formation inhibitory activity was developed by combining biofilm formation on pins of microtiter plate lids and staining using crystal violet. The optimum conditions for biofilm formation on the pins were established for seven Gram-positive and six Gram-negative bacteria by investigations of media, incubation time, and pin materials. Minimum concentrations of food additives required to inhibit biofilm formation were determined using the proposed method. The values obtained by the proposed and conventional methods agreed well. In addition, by sequential measurements of minimum inhibitory concentrations and minimum bactericidal concentrations using the proposed method, mechanisms of inhibition of biofilm formation were assessed. Furthermore, inhibitory activities of the water extracts of 498 different plant foodstuffs on biofilm formation by Streptococcus mutans were measured; five of the extracts showed potent inhibitory activities. The method proposed here circumvents the tedious and time-consuming conventional method in which biofilms are cultivated on the bottom of wells of microtiter plates.

American cranberries and health benefits - an evolving story of 25 years

Cranberries contain various types of bioactive components. Scientists have been studying cranberries' beneficial effects on urinary tract health since the 20th century. In the 21st century, the protection provided by cranberry phytochemicals against cancer and vascular diseases has drawn more attention from researchers. Anthocyanins, procyanidins, and flavonols in cranberries were all documented to have potential effects on cancer prevention. The cardiometabolic effects of cranberries have been investigated in several clinical trials. It was found that cranberries positively affect atherosclerotic cholesterol profiles and that they reduced several cardiometabolic risk factors. Nowadays, growing evidence suggests other important roles of cranberries in maintaining digestive health. Cranberry juice or cranberries have been shown to inhibit the colonization of H. pylori in stomach, and protect against intestinal inflammation. For future research, clinical trials with improved study design are urgently needed to demonstrate cranberries' benefits on urinary tract health and cardiometabolic diseases. Hypothesis-driven studies using animals or cell culture are needed to elucidate the mechanisms of cranberries' effects on digestive health. © 2018 Society of Chemical Industry.

Anti-adhesive activity of a Vaccinium corymbosum polyphenolic extract targeting intestinal colonization by Klebsiella pneumoniae

The therapeutic effect of Vaccinium polyphenols against uropathogens has been widely studied. Most attention has focused on the antimicrobial activity against P-fimbriated Escherichia coli strains. The present study investigated the anti-adhesive and anti-biofilm activity of a saline extract of blueberry (Vaccinium corymbosum) targeting intestinal colonization by a highly adherent Klebsiella pneumoniae strain. This strain, responsible for a large outbreak of infection in Spain, was selected on the basis of its remarkable capacity to colonize the gastrointestinal tract of patients. The blueberry extract was obtained using a medium scale ambient temperature system (MSAT) in a novel approach based on the use of an aqueous solvent and addition of mineral salts. The polyphenolic content was determined by liquid chromatography coupled to tandem mass-spectrometry (LC-MS/MS). The findings confirmed that the blueberry extract is a rich source of phenolic compounds, including the most polar polyphenols (mostly non-flavonoids), intermediate polarity compounds (flavan-3-ols and most procyanidins) and low polarity compounds (flavonols and anthocyanins). The extract significantly inhibited biofilm formation and bacterial adhesion to HT-29 colorectal cells by a highly adherent multidrug-resistant K. pneumoniae. Although some individual anthocyanidins (malvidin, delphinidin and cyanidin) and one hydroxycinnamic acid (caffeic acid) proved capable of reducing bacterial adhesion, the unfractionated extract was more active than any of the individual polyphenolic compounds. In addition, the extract displayed considerable potential as an intestinal decolonization treatment in a murine model. The study findings demonstrate the potential value of the V. corymbosum extract as an alternative treatment for K. pneumoniae infections.

Natural therapeutics for urinary tract infections-a review

Background

The recurrence of the urinary tract infections (UTI), following the antibiotic treatments suggests the pathogen’s resistance to conventional antibiotics. This calls for the exploration of an alternative therapy.

Main body

The anti-uropathogenic and bactericidal activity of many plant extracts was reported by many researchers, which involves only preliminary antibacterial studies using different basic techniques like disk diffusion, agar well diffusion, or minimum inhibitory concentration (MIC) of the crude plant extracts, but reports on the specific action of the phytoconstituents against uropathogens are limited. Vaccinium macrocarpon Aiton (cranberry) is the best-studied home remedy for UTI. Some evidences suggest that proanthocyanins present in cranberry, prevent bacteria from adhering to the walls of the urinary tract, subsequently blocking the further steps of uropathogenesis. Probiotics such as Lactobacillus and Bifidobacterium are beneficial microorganisms that may act by the competitive exclusion principle to defend against infections in the urogenital tracts. Reports on potential vaccine agents and antibodies targeting the different toxins and effecter proteins are still obscure except uropathogenic E. coli.

Conclusion

This review highlights some of the medicinal herbs used by aborigines to prevent or treat acute or chronic urinary tract infections, botanicals with established urobactericidal activity, clinical trials undertaken to compare the efficacy of cranberry products in UTI prevention, and other natural therapeutics reported for UTI.

Berry Polyphenols and Fibers Modulate Distinct Microbial Metabolic Functions and Gut Microbiota Enterotype-Like Clustering in Obese Mice

Berries are rich in polyphenols and plant cell wall polysaccharides (fibers), including cellulose, hemicellulose, arabinans and arabino-xyloglucans rich pectin. Most of polyphenols and fibers are known to be poorly absorbed in the small intestine and reach the colon where they interact with the gut microbiota, conferring health benefits to the host. This study assessed the contribution of polyphenol-rich whole cranberry and blueberry fruit powders (CP and BP), and that of their fibrous fractions (CF and BF) on modulating the gut microbiota, the microbial functional profile and influencing metabolic disorders induced by high-fat high-sucrose (HFHS) diet for 8 weeks. Lean mice-associated taxa, including Akkermansia muciniphila, Dubosiella newyorkensis, and Angelakisella, were selectively induced by diet supplementation with polyphenol-rich CP and BP. Fiber-rich CF also triggered polyphenols-degrading families Coriobacteriaceae and Eggerthellaceae. Diet supplementation with polyphenol-rich CP, but not with its fiber-rich CF, reduced fat mass depots, body weight and energy efficiency in HFHS-fed mice. However, CF reduced liver triglycerides in HFHS-fed mice. Importantly, polyphenol-rich CP-diet normalized microbial functions to a level comparable to that of Chow-fed controls. Using multivariate association modeling, taxa and predicted functions distinguishing an obese phenotype from healthy controls and berry-treated mice were identified. The enterotype-like clustering analysis underlined the link between a long-term diet intake and the functional stratification of the gut microbiota. The supplementation of a HFHS-diet with polyphenol-rich CP drove mice gut microbiota from Firmicutes/Ruminococcus enterotype into an enterotype linked to healthier host status, which is Prevotella/Akkermansiaceae. This study highlights the prebiotic role of polyphenols, and their contribution to the compositional and functional modulation of the gut microbiota, counteracting obesity.

Plant-Based Phytochemicals as Possible Alternative to Antibiotics in Combating Bacterial Drug Resistance

The unprecedented use of antibiotics that led to development of resistance affect human health worldwide. Prescription of antibiotics imprudently and irrationally in different diseases progressed with the acquisition and as such development of antibiotic resistant microbes that led to the resurgence of pathogenic strains harboring enhanced armors against existing therapeutics. Compromised the treatment regime of a broad range of antibiotics, rise in resistance has threatened human health and increased the treatment cost of diseases. Diverse on metabolic, genetic and physiological fronts, rapid progression of resistant microbes and the lack of a strategic management plan have led researchers to consider plant-derived substances (PDS) as alternative or in complementing antibiotics against the diseases. Considering the quantitative characteristics of plant constituents that attribute health beneficial effects, analytical procedures for their isolation, characterization and phytochemical testing for elucidating ethnopharmacological effects has being worked out for employment in the treatment of different diseases. With an immense potential to combat bacterial infections, PDSs such as polyphenols, alkaloids and tannins, present a great potential for use, either as antimicrobials or as antibiotic resistance modifiers. The present study focuses on the mechanisms by which PDSs help overcome the surge in resistance, approaches for screening different phytochemicals, methods employed in the identification of bioactive components and their testing and strategies that could be adopted for counteracting the lethal consequences of multidrug resistance.

Comparison of enzymatic and microwave-assisted alkaline extraction approaches for the generation of oligosaccharides from American Cranberry (Vaccinium macrocarpon) Pomace

Cranberry pomace obtained from industrial juice production was characterized by proximate composition analysis and monosaccharide profile of the dietary fiber. Extraction of carbohydrates from pomace was investigated using microwave-assisted alkaline method and five commercial biocatalysts (pure endo-galactanase and four multienzyme biocatalysts). The extracts obtained from microwave-assisted approach had average total sugars yield of 21.3% and contained mostly oligosaccharides in the degree of polymerization range of 7 to 10. All multienzyme biocatalysts led to yields similar or higher than microwave-assisted approach (23.4% to 42.0%), but mainly generated shorter oligosaccharides with a degree of polymerization of 2 to 5. Compared to cranberry pomace dietary fiber, microwave-assisted extracts were enriched in pectic oligosaccharides, whereas the enzymatic extracts were enriched in glucans and had less rhamnose and galactose. Pomace ground for 5 min or more by ball mill assumed a powdery consistence. Longer milling did not affect particle size but increased their roughness. Such physical changes had no effect on the efficiency of multienzymatic treatment. PRACTICAL APPLICATION: The increased production of cranberries and cranberry products will continuously generate more pomace, a potentially valuable material for the generation of added-value products. Up to 60% to 70% of cranberry pomace is composed of plant cell wall material. The properties of naturally occurring plant cell wall polysaccharides and their corresponding oligosaccharides have been of a great interest, and many of them find application as functional food ingredients. Despite the fact that the cranberry pomace is rich in plant cell polysaccharides, it has been mainly explored as a source of phenolic antioxidants. This study reveals the efficiency of cranberry pomace as a source of nondigestible oligosaccharides. The use of microwave-assisted extraction and different biocatalysts for the enzymatic extraction led to oligosaccharides with well-defined monosaccharide composition and molecular weight distribution. The study of the effects of these extraction techniques on the yield and the characteristics of generated oligosaccharides would allow the modulation of their properties. As an overall, the findings of this study would contribute to lay the scientific ground for the development of innovative process for the isolation of nondigestible oligosaccharides as functional ingredients from cranberry pomace by products.

Evolution of cranberry juice compounds during in vitro digestion and identification of the organic acid responsible for the disruption of in vitro intestinal cell barrier integrity

Cranberry juice is increasingly consumed for its richness in polyphenols having a positive impact on human health. Unfortunately, when regularly consumed, its high concentration in organic acids may cause some intestinal discomforts. In the present study, its organic acid content was reduced of 41% by electrodialysis with bipolar membrane (EDBM), and the resulted deacidified juice was divided in five different juices readjusted or not with different concentrations of citric and/or malic acid(s) corresponding to the concentration of this/these acid(s) recovered during EDBM or at the titratable acidity (TA) of the non-deacidified cranberry juice. The evolution of the cranberry juice main interesting compounds (organic acids and polyphenols), according to the concentration and nature of the organic acids present, was studied for the first time at each specific stages of the digestion. After digestion, Caco-2 cells were exposed to all digested juices to identify the organic acid(s) responsible for the loss of integrity of the epithelial barrier. It appeared that organic acid contents did not change during the different steps of the digestion while polyphenolic compounds decreased starting from the gastric phase. Whatever the organic acid concentration or nature, the concentration of PACs significantly decreased between the salivary and the gastric steps but was different according to their structure when the concentration of most of anthocyanins significantly decreased at the gastric step. Also, to the best of our knowledge, it was the first time that citric acid was demonstrated as the organic acid responsible for the loss of integrity of Caco-2 cell monolayers.

New Evidences of Antibacterial Effects of Cranberry Against Periodontal Pathogens

The worrying rise in antibiotic resistances emphasizes the need to seek new approaches for treating and preventing periodontal diseases. The purpose of this study was to evaluate the antibacterial and anti-biofilm activity of cranberry in a validated in vitro biofilm model. After chemical characterization of a selected phenolic-rich cranberry extract, its values for minimum inhibitory concentration and minimum bactericidal concentration were calculated for the six bacteria forming the biofilm (Streptococcus oralis, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans). Antibacterial activity of the cranberry extract in the formed biofilm was evaluated by assessing the reduction in bacteria viability, using quantitative polymerase chain reaction (qPCR) combined with propidium monoazide (PMA), and by confocal laser scanning microscopy (CLSM), and anti-biofilm activity by studying the inhibition of the incorporation of different bacteria species in biofilms formed in the presence of the cranberry extract, using qPCR and CLSM. In planktonic state, bacteria viability was significantly reduced by cranberry (p < 0.05). When growing in biofilms, a significant effect was observed against initial and early colonizers (S. oralis (p ≤ 0.017), A. naeslundii (p = 0.006) and V. parvula (p = 0.010)) after 30 or 60 s of exposure, while no significant effects were detected against periodontal pathogens (F. nucleatum, P. gingivalis or A. actinomycetemcomitans (p > 0.05)). Conversely, cranberry significantly (p < 0.001 in all cases) interfered with the incorporation of five of the six bacteria species during the development of 6 h-biofilms, including P. gingivalis, A. actinomycetemcomitans, and F. nucleatum. It was concluded that cranberry had a moderate antibacterial effect against periodontal pathogens in biofilms, but relevant anti-biofilm properties, by affecting bacteria adhesion in the first 6 h of development of biofilms.

Oligosaccharides and Complex Carbohydrates: A New Paradigm for Cranberry Bioactivity

Cranberry is a well-known functional food, but the compounds directly responsible for many of its reported health benefits remain unidentified. Complex carbohydrates, specifically xyloglucan and pectic oligosaccharides, are the newest recognized class of biologically active compounds identified in cranberry materials. Cranberry oligosaccharides have shown similar biological properties as other dietary oligosaccharides, including effects on bacterial adhesion, biofilm formation, and microbial growth. Immunomodulatory and anti-inflammatory activity has also been observed. Oligosaccharides may therefore be significant contributors to many of the health benefits associated with cranberry products. Soluble oligosaccharides are present at relatively high concentrations (~20% w/w or greater) in many cranberry materials, and yet their possible contributions to biological activity have remained unrecognized. This is partly due to the inherent difficulty of detecting these compounds without intentionally seeking them. Inconsistencies in product descriptions and terminology have led to additional confusion regarding cranberry product composition and the possible presence of oligosaccharides. This review will present our current understanding of cranberry oligosaccharides and will discuss their occurrence, structures, ADME, biological properties, and possible prebiotic effects for both gut and urinary tract microbiota. Our hope is that future investigators will consider these compounds as possible significant contributors to the observed biological effects of cranberry.

Pectic Oligosaccharides from Cranberry Prevent Quiescence and Persistence in the Uropathogenic Escherichia coli CFT073

Urinary tract infections (UTIs) caused by Escherichia coli create a large burden on healthcare and frequently lead to recurrent infections. Part of the success of E. coli as an uropathogenic bacterium can be attributed to its ability to form quiescent intracellular reservoirs in bladder cells and its persistence after antibiotic treatment. Cranberry juice and related products have been used for the prevention of UTIs with varying degrees of success. In this study, a group of cranberry pectic oligosaccharides (cPOS) were found to both inhibit quiescence and reduce the population of persister cells formed by the uropathogenic strain, CFT073. This is the first report detailing constituents of cranberry with the ability to modulate these important physiological aspects of uropathogenic E. coli. Further studies investigating cranberry should be keen to include oligosaccharides as part of the ‘active’ cocktail of chemical compounds.

The Role of Drug Repurposing in the Development of Novel Antimicrobial Drugs: Non-Antibiotic Pharmacological Agents as Quorum Sensing-Inhibitors

Background: The emergence of multidrug-resistant organisms (MDROs) is a global public health issue, severely hindering clinicians in administering appropriate antimicrobial therapy. Drug repurposing is a drug development strategy, during which new pharmacological applications are identified for already approved drugs. From the viewpoint of the development of virulence inhibitors, inhibition of quorum sensing (QS) is a promising route because various important features in bacterial physiology and virulence are mediated by QS-dependent gene expression. Methods: Forty-five pharmacological agents, encompassing a wide variety of different chemical structures and mechanisms of action, were tested during our experiments. The antibacterial activity of the compounds was tested using the broth microdilution method. Screening and semi-quantitative assessment of QS-inhibition by the compounds was performed using QS-signal molecule-producing and indicator strains. Results: Fourteen pharmaceutical agents showed antibacterial activity in the tested concentration range, while eight drugs (namely 5-fluorouracil, metamizole-sodium, cisplatin, methotrexate, bleomycin, promethazine, chlorpromazine, and thioridazine) showed dose-dependent QS-inhibitory activity in the in vitro model systems applied during the experiments. Conclusions: Virulence inhibitors represent an attractive alternative strategy to combat bacterial pathogens more efficiently. Some of the tested compounds could be considered potential QS-inhibitory agents, warranting further experiments involving additional model systems to establish the extent of their efficacy.

Plant-Derived Products as Antibacterial and Antifungal Agents in Human Health Care

A number of papers reporting antimicrobial properties of extracts, essential oils, resins and various classes of compounds isolated from higher plants have been published in recent years; however, a comprehensive analysis of plant-derived antimicrobial agents currently applied in practice for the improvement of human health is still lacking. This review summarizes data on clinical efficacy, antimicrobial effects and the chemistry of commercially available antibacterial and antifungal agents of plant origin currently used in the prevention and treatment of gastrointestinal, oral, respiratory, skin, and urinary infections. As a result of an analysis of the literature, more than 40 plant-derived over-the-counter pharmaceuticals, dietary supplements, cosmetics, herbal medicines, and functional foods containing complex mixtures (e.g. Glycyrrhiza glabra extract, Melaleuca alternifolia essential oil, and Pistacia lentiscus resin), pure compounds (e.g. benzoic acid, berberine, eucalyptol, salicylic acid and thymol) as well as their derivatives and complexes (e.g. bismuth subsalicylate and zinc pyrithione) have been identified. The effectiveness of many of these products is illustrated by results of clinical trials and supported by data on there in vitro antimicrobial activity. A broad spectrum of various commercial products currently available on the market and their welldocumented clinical efficacy suggests that plants are prospective sources for the identification of new types of antimicrobial agents in future. Innovative approaches and methodologies for effective proof-of-concept research and the development of new types of plant-derived products effective against recently emerging problems related to human microbial diseases (e.g. antimicrobial resistance) are also proposed in this review.

A Review of Nonantibiotic Agents to Prevent Urinary Tract Infections in Older Women

OBJECTIVE

This article provides a comprehensive literature review on nonantibiotic agents used for the prevention of urinary tract infections (UTIs) in women ≥45 years of age.

DESIGN

A structured review was performed by conducting a literature search to identify relevant studies pertaining to the use of nonantibiotic agents to prevent UTIs in women who were perimenopausal through postmenopausal. Recommendations were made for or against the use of each nonantibiotic agent, unless data were unavailable. Levels of evidence were assigned to each recommendation made.

SETTING AND PARTICIPANTS

Studies on the prevention of UTIs with women subjects ≥45 years of age in the community, inpatient, and long-term care settings were considered for inclusion.

MEASURE

The efficacy and safety of using ascorbic acid, cranberry products, d-mannose, estrogens, lactobacilli, and methenamine hippurate for prevention of UTIs was assessed.

RESULTS

There is evidence to support use of estrogens (A-I) in postmenopausal women, and cranberry capsules (C-I) in women ≥45 years of age for the prevention of UTIs. There was a lack of evidence to make recommendations for or against the use of ascorbic acid, cranberry juice, cranberry capsules with high proanthocyanidin (PAC) content, d-mannose, lactobacillus, and methenamine hippurate in this population.

CONCLUSIONS/IMPLICATIONS

Current studies support that estrogens and cranberry capsules may have a role in preventing UTIs in women ≥45 years of age. Further research is needed to elucidate the role of these nonantibiotic agents and how they may be used to decrease antibiotic use.

Structural Characterization of Cranberry Arabinoxyloglucan Oligosaccharides

Cranberry ( Vaccinium macrocarpon) products are widely available in North American food, juice, and dietary supplement markets. The use of cranberry is popular for the prevention of urinary tract infections (UTIs) and other reported health benefits. Preliminary findings by our research group indicate that arabinoxyloglucan oligosaccharides are present in cranberry products and may contribute to the antiadhesion properties of urine produced after cranberry consumption, but relatively little is known regarding the oligosaccharide components of cranberry. This report describes the isolation from two cranberry sources and the complete structure elucidation of two arabinoxyloglucan oligosaccharides through the use of carbohydrate-specific NMR spectroscopic and chemical derivatization methods. These compounds were identified as the heptasaccharide β-d-glucopyranosyl-(1→4)-[α-d-xylopyranosyl-(1→6)]-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-β-d-glucopyranose (1) and the octasaccharide β-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-β-d-glucopyranose (2). Selected fractions and the isolated compounds were subjected to antimicrobial, cell viability, and E. coli antiadhesion assays. Results indicated that enriched fractions and purified compounds lacked antimicrobial and cytotoxic effects, supporting the potential use of such compounds for disease prevention without the risk for resistance development. Preliminary antiadhesion results indicated that mixtures of oligosaccharides exhibited greater antiadhesion properties than purified fractions or pure compounds. The potential use of cranberry oligosaccharides for the prevention of UTIs warrants continued investigations of this complex compound series.

Arabinoxyloglucan Oligosaccharides May Contribute to the Antiadhesive Properties of Porcine Urine after Cranberry Consumption

Cranberry ( Vaccinium macrocarpon) juice is traditionally used for the prevention of urinary tract infections. Human urine produced after cranberry juice consumption can prevent Escherichia coli adhesion, but the antiadhesive urinary metabolites responsible have not been conclusively identified. Adult female sows were therefore fed spray-dried cranberry powder (5 g/kg/day), and urine was collected via catheter. Urine fractions were tested for antiadhesion activity using a human red blood cell (A+) anti-hemagglutination assay with uropathogenic P-fimbriated E. coli. Components were isolated from fractions of interest using Sephadex LH-20 gel filtration chromatography followed by HPLC on normal and reversed-phase sorbents with evaporative light scattering detection. Active urine fractions were found to contain a complex series of oligosaccharides but not proanthocyanidins, and a single representative arabinoxyloglucan octasaccharide was isolated in sufficient quantity and purity for full structural characterization by chemical derivatization and NMR spectroscopic methods. Analogous cranberry material contained a similar complex series of arabinoxyloglucan oligosaccharides that exhibited antiadhesion properties in preliminary testing. These results indicate that oligosaccharides structurally related to those found in cranberry may contribute to the antiadhesion properties of urine after cranberry consumption.

Chemopreventive Effects of Whole Cranberry (Vaccinium macrocarpon) on Colitis-Associated Colon Tumorigenesis

SCOPE

There are growing interests in using a whole-food-based approach to prevent chronic diseases due to potential synergistic interactions among different bioactive components within the whole foods. North American cranberry (Vaccinium macrocarpon), a polyphenol-rich fruit, has been shown to exert multiple beneficial health effects.

METHODS AND RESULTS

For the first time, the protective effects of whole cranberry powder (WCP) are determined against colitis-associated mouse colon tumorigenesis induced by azoxymethane (AOM) and dextran sulfate sodium (DSS). The results show that dietary administration of WCP (1.5%, w/w in the diet) significantly suppresses colon tumorigenesis as indicated by the reduced tumor incidence, multiplicity, burden, and average tumor size in WCP-fed mice compared to the positive control mice. Both gene and protein expression levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α are markedly attenuated by WCP treatment in the colon of AOM/DSS-treated mice. Moreover, WCP profoundly modulates multiple signaling pathways/proteins related to inflammation, cell proliferation, apoptosis, angiogenesis, and metastasis in the colon, which is closely associated with the inhibitory effects of WCP on colon tumorigenesis.

CONCLUSION

Overall, the results demonstrate chemopreventive effects of WCP on colon tumorigenesis in mice, providing a scientific basis for using the whole cranberry as a functional food to promote colon health in humans.

Propolis potentiates the effect of cranberry (Vaccinium macrocarpon) in reducing the motility and the biofilm formation of uropathogenic Escherichia coli

One strategy to prevent urinary tract infections is the use of natural products such as cranberry (Vaccinium macrocarpon) and propolis. The objective of this study was to evaluate the impact of these products alone and combined on the motility and biofilm formation of a collection of representative uropathogenic Escherichia coli (UPEC). Motility was evaluated by the swarming and swimming capacity of the isolates in presence/absence of cranberry ± propolis. Early and late biofilm formation was observed with the Biofilm Ring test (BioFilm Control) and the crystal violet method. Cranberry alone was seen to have a variable effect on motility and biofilm formation unrelated to bacterial characteristics, but a reduced motility and biofilm formation was observed for all the isolates in the presence of cranberry + propolis. These results suggest that cranberry alone doesn’t work on all the E. coli strains and propolis potentiates the effect of cranberry on UPEC, representing a new strategy to prevent recurrent urinary tract infections.

Effective anti-adhesives of uropathogenic Escherichia coli

Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) are among the most common infectious diseases in humans. Due to their frequent occurrence in the community and nosocomial settings, as well as the development of resistance to the commonly prescribed antimicrobial agents, an enormous financial burden is placed on healthcare systems around the world. Therefore, novel approaches to the prevention and treatment of UTIs are needed. Although UPEC may harbour a plethora of virulence factors, type I fimbriae and P pili are two of the most studied adhesive organelles, since the attachment to host cells in the urinary tract is a crucial step towards infection. Design of receptor analogues that competitively bind to UPEC surface adhesins placed at the top of pili organelles led to the development of anti-adhesive drugs that are increasingly recognized as important and promising alternatives to antibiotic treatment of UTIs.

Propolis potentiates the effect of cranberry (Vaccinium macrocarpon) against the virulence of uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC), the most prevalent bacteria isolated in urinary tract infections (UTI), is now frequently resistant to antibiotics used to treat this pathology. The antibacterial properties of cranberry and propolis could reduce the frequency of UTIs and thus the use of antibiotics, helping in the fight against the emergence of antibiotic resistance. Transcriptomic profiles of a clinical UPEC strain exposed to cranberry proanthocyanidins alone (190 µg/mL), propolis alone (102.4 µg/mL) and a combination of both were determined. Cranberry alone, but more so cranberry + propolis combined, modified the expression of genes involved in different essential pathways: down-expression of genes involved in adhesion, motility, and biofilm formation, and up-regulation of genes involved in iron metabolism and stress response. Phenotypic assays confirmed the decrease of motility (swarming and swimming) and biofilm formation (early formation and formed biofilm). This study showed for the first time that propolis potentiated the effect of cranberry proanthocyanidins on adhesion, motility, biofilm formation, iron metabolism and stress response of UPEC. Cranberry + propolis treatment could represent an interesting new strategy to prevent recurrent UTI.

Characterization of non-dialyzable constituents from cranberry juice that inhibit adhesion, co-aggregation and biofilm formation by oral bacteria

An extract prepared from cranberry juice by dialysis known as nondialyzable material (NDM) has been shown previously to possess anti-adhesion activity toward microbial species including oral bacteria, uropathogenic Escherichia coli and Helicobacter pylori. Bioassay-guided fractionation of cranberry NDM was therefore undertaken to identify the anti-adhesive constituents. An aqueous acetone-soluble fraction (NDMac) obtained from Sephadex LH-20 inhibited adhesion-linked activities by oral bacteria, including co-aggregation of oral bacteria Fusobacterium nucleatum with Streptococcus sanguinis or Porphyromonas gingivalis, and biofilm formation by Streptococcus mutans. Analysis of NDMac and subsequent subfractions by MALDI-TOF MS and ¹H NMR revealed the presence of A-type proanthocyanidin oligomers (PACs) of 3-6 degrees of polymerization composed of (epi)catechin units, with some (epi)gallocatechin and anthocyanin units also present, as well as quercetin derivatives. Subfractions containing putative xyloglucans in addition to the mixed polyphenols also inhibit biofilm formation by S. mutans (MIC = 125-250 μg mL^-1). These studies suggest that the anti-adhesion activities of cranberry NDM on oral bacteria may arise from a combination of mixed polyphenol and non-polyphenol constituents.

A Human Gut Commensal Ferments Cranberry Carbohydrates To Produce Formate

Commensal bifidobacteria colonize the human gastrointestinal tract and catabolize glycans that are impervious to host digestion. Accordingly, Bifidobacterium longum typically secretes acetate and lactate as fermentative end products. This study tested the hypothesis that B. longum utilizes cranberry-derived xyloglucans in a strain-dependent manner. Interestingly, the B. longum strain that efficiently utilizes cranberry xyloglucans secretes 2.0 to 2.5 mol of acetate-lactate. The 1.5 acetate:lactate ratio theoretical yield obtained in hexose fermentations shifts during xyloglucan metabolism. Accordingly, this metabolic shift is characterized by increased acetate and formate production at the expense of lactate. α-l-Arabinofuranosidase, an arabinan endo-1,5-α-l-arabinosidase, and a β-xylosidase with a carbohydrate substrate-binding protein and carbohydrate ABC transporter membrane proteins are upregulated (>2-fold change), which suggests carbon flux through this catabolic pathway. Finally, syntrophic interactions occurred with strains that utilize carbohydrate products derived from initial degradation from heterologous bacteria.IMPORTANCE This was a study of bacterial metabolism of complex cranberry carbohydrates termed xyloglucans that are likely not digested prior to reaching the colon. This is significant, as bifidobacteria interact with this dietary compound to potentially impact human host health through energy and metabolite production by utilizing these substrates. Specific bacterial strains utilize cranberry xyloglucans as a nutritive source, indicating unknown mechanisms that are not universal in bifidobacteria. In addition, xyloglucan metabolism proceeds by using an alternative pathway that could lead to further research to investigate mechanisms underlying this interaction. Finally, we observed cross-feeding between bacteria in which one strain degrades the cranberry xyloglucan to make it available to a second strain. Similar nutritive strategies are known to occur within the gut. In aggregate, this study may lead to novel foods or supplements used to impact human health through rational manipulation of the human microbiome.

Extract of Clinopodium bolivianum protects against E. coli invasion of uroepithelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Clinopodium bolivianum is a South American plant with anti-inflammatory and anti-infective activities. The increasing antibiotic resistance urges for alternative therapy. Based on its use in traditional medicine, we investigated the effect of C. bolivianum on the ability to defend bladder epithelial cells from E. coli infection.

MATERIALS AND METHODS

The extract was analyzed by LC-MS. Bladder epithelial cell lines T24 and 5637 and uropathogenic E. coli No. 12, its isogenic mutant WE16 csgBA bscA::Cm and CFT073 were used to investigate the effect of C. bolivianum on uroepithelial infection. Bacterial adherence and invasion to cells treated with C. bolivianum were analyzed. Expression of uroplakin 1a, β1 integrin, caveolin-1, IL-8 and antimicrobial peptides in response to C. bolivianum treatment was assessed using RT-PCR. Protein expression was confirmed by Western blot analysis or ELISA. The antimicrobial effects of C. bolivianum on bacteria and fungus were investigated using minimum inhibitory concentration. Furthermore, the formation of biofilm was investigated with crystal violet assay.

RESULTS

C. bolivianum extract consisted of more than 70 different types of phytochemicals including sugars and phenolic compounds. The extract decreased the uroplakin 1a expression and E. coli adhesion and invasion of uroepithelial cells while up-regulated caveolin-1. In uninfected C. bolivianum treated cells, IL-8 was lower than in non-treated cells. In infected cells, however, no difference was observed between treated and non-treated cells. Further, C. bolivianum treatment reduced uropathogenic E. coli (UPEC) biofilms but did not inhibit bacterial growth.

CONCLUSIONS

Our results show that C. bolivianum has a protective role on bladder epithelial cells against UPEC infection by decreasing the bacterial adhesion, invasion and biofilm formation.

Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup

Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

Impact of Cranberries on Gut Microbiota and Cardiometabolic Health: Proceedings of the Cranberry Health Research Conference 2015

Recent advances in cranberry research have expanded the evidence for the role of this Vaccinium berry fruit in modulating gut microbiota function and cardiometabolic risk factors. The A-type structure of cranberry proanthocyanidins seems to be responsible for much of this fruit's efficacy as a natural antimicrobial. Cranberry proanthocyanidins interfere with colonization of the gut by extraintestinal pathogenic Escherichia coli in vitro and attenuate gut barrier dysfunction caused by dietary insults in vivo. Furthermore, new studies indicate synergy between these proanthocyanidins, other cranberry components such as isoprenoids and xyloglucans, and gut microbiota. Together, cranberry constituents and their bioactive catabolites have been found to contribute to mechanisms affecting bacterial adhesion, coaggregation, and biofilm formation that may underlie potential clinical benefits on gastrointestinal and urinary tract infections, as well as on systemic anti-inflammatory actions mediated via the gut microbiome. A limited but growing body of evidence from randomized clinical trials reveals favorable effects of cranberry consumption on measures of cardiometabolic health, including serum lipid profiles, blood pressure, endothelial function, glucoregulation, and a variety of biomarkers of inflammation and oxidative stress. These results warrant further research, particularly studies dedicated to the elucidation of dose-response relations, pharmacokinetic/metabolomics profiles, and relevant biomarkers of action with the use of fully characterized cranberry products. Freeze-dried whole cranberry powder and a matched placebo were recently made available to investigators to facilitate such work, including interlaboratory comparability.

Effect of cranberry (Vaccinium macrocarpon) oligosaccharides on the formation of advanced glycation end-products

BACKGROUND: The formation and accumulation of advanced glycation end-products (AGEs) are implicated in several chronic human illnesses including type-2 diabetes, renal failure, and neurodegenerative diseases. The cranberry (Vaccinium macrocarpon) fruit has been previously reported to show anti-AGEs effects, attributed primarily to its phenolic constituents. However, there is lack of similar data on the non-phenolic constituents found in the cranberry fruit, in particular, its carbohydrate constituents. Herein, a chemically characterized oligosaccharide-enriched fraction purified from the cranberry fruit was evaluated for its potential anti-AGEs and free radical scavenging effects. OBJECTIVE: The aim of this study was to evaluate the in vitro anti-AGEs and free radical scavenging effects of a chemically characterized oligosaccharide-enriched fraction purified from the North American cranberry (Vaccinium macrocarpon) fruit. METHOD: The cranberry oligosaccharide-enriched fraction was purified from cranberry hull powder and characterized based on spectroscopic and spectrometric (NMR, MALDI-TOF-MS, and HPAEC-PAD) data. The oligosaccharide-enriched fraction was evaluated for its anti-AGEs and free radical scavenging effects by the bovine serum albumin-fructose, and DPPH assays, respectively. RESULTS: Fractionation of cranberry hull material yielded an oligosaccharide-enriched fraction named Cranf1b-CL. The ¹H NMR and MALDI-TOF-MS revealed that Cranf1b-CL consists of oligosaccharides ranging primarily from 6-mers to 9-mers. The monosaccharide composition of Cranf1b-CL was arabinose (25%), galactose (5%), glucose (47%) and xylose (23%). In the bovine serum albumin-fructose assay, Cranf1b-CL inhibited AGEs formation in a concentration-dependent manner with comparable activity to the synthetic antiglycating agent, aminoguanidine, used as the positive control (57 vs. 75%; both at 500μg/mL). In the DPPH free radical scavenging assay, Cranf1b-CL showed superior activity to the synthetic commercial antioxidant, butylated hydroxytoluene, used as the positive control (IC₅₀ = 680 vs. 2200μg/mL, respectively). CONCLUSION: The in vitro anti-AGEs and free radical scavenging effects of cranberry oligosaccharides support previous data suggesting that these constituents may also contribute to biological effects of the whole fruit beyond its phenolic constituents alone. Also, this is the first study to evaluate a chemically characterized oligosaccharide fraction purified from the North American cranberry fruit for anti-AGEs and free radical scavenging properties.

Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli

Characterization of cranberry juice fractions for their role in anti-adhesive properties against pathogenicE. coliusing Atomic Force Microscopy (AFM).

Bioactive Compounds and Antioxidant Activity in Different Types of Berries

Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry), and Ericaceae (blueberry, cranberry), belong to the best dietary sources of bioactive compounds (BAC). They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins) and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits.