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Miscellaneous: In-Vitro

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Inhibition of herpes simplex type 1 and type 2 infections by Oximacro, a cranberry extract with a high content of A-type proanthocyanidins (PACs-A)

Posted: 
August 22, 2016
Authors: 
Terlizzi ME; Occhipinti A; Luganini A; Maffei ME; Gribaudo G.
Journal: 
Antiviral Research. 132 (pp 154-164),
Abstract: 

In the absence of efficient preventive vaccines, topical microbicides offer an attractive alternative in the prevention of Herpes simplex type 1 (HSV-1) and type 2 (HSV-2) infections. Because of their recognized anti-adhesive activity against bacterial pathogens, cranberry (Vaccinium macrocarpon Ait.) extracts may represent a natural source of new antiviral microbicides. However, few studies have addressed the applications of cranberry extract as a direct-acting antiviral agent. Here, we report on the ability of the novel cranberry extract Oximacro and its purified A-type proanthocyanidins (PACs-A), to inhibit HSV-1 and HSV-2 replication in vitro. Analysis of the mode of action revealed that Oximacro prevents adsorption of HSV-1 and HSV-2 to target cells. Further mechanistic studies confirmed that Oximacro and its PACs-A target the viral envelope glycoproteins gD and gB, thus resulting in the loss of infectivity of HSV particles. Moreover, Oximacro completely retained its anti-HSV activity even at acidic pHs (3.0 and 4.0) and in the presence of 10% human serum proteins; conditions that mimic the physiological properties of the vagina - a potential therapeutic location for Oximacro. Taken together, these findings indicate Oximacro as an attractive candidate for the development of novel microbicides of natural origin for the prevention of HSV infections.

Adherence Reduction of Campylobacter jejuni and Campylobacter coli Strains to HEp-2 Cells by Mannan Oligosaccharides and a High-Molecular-Weight Component of Cranberry Extract.

Posted: 
March 23, 2016
Authors: 
Ramirez-Hernandez A, Rupnow J, Hutkins RW
Journal: 
J Food Prot 78(8):1496-505
Abstract: 

Campylobacter infections are a leading cause of human bacterial gastroenteritis in the United States and are a major cause of diarrheal disease throughout the world. Colonization and subsequent infection and invasion of Campylobacter require that the bacteria adhere to the surface of host cells. Agents that inhibit adherence could be used prophylactically to reduce Campylobacter carriage and infection. Mannan oligosaccharides (MOS) have been used as a feed supplement in livestock animals to improve performance and to replace growth-promoting antibiotics. However, MOS and other nondigestible oligosaccharides may also prevent pathogen colonization by inhibiting adherence in the gastrointestinal tract. In addition, plant extracts, including those derived from cranberries, have been shown to have antiadherence activity against pathogens. The goal of this study was to assess the ability of MOS and cranberry fractions to serve as antiadherence agents against strains of Campylobacter jejuni and Campylobacter coli. Adherence experiments were performed using HEp-2 cells. Significant reductions in adherence of C. jejuni 29438, C. jejuni 700819, C. jejuni 3329, and C. coli 43485 were observed in the presence of MOS (up to 40 mg/ml) and with a high-molecular-weight fraction of cranberry extract (up to 3 mg/ml). However, none of the tested materials reduced adherence of C. coli BAA-1061. No additive effect in adherence inhibition was observed for an MOS-cranberry blend. These results suggest that both components, MOS and cranberry, could be used to reduce Campylobacter colonization and carriage in livestock animals and potentially limit human exposure to this pathogen.

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

Posted: 
March 23, 2016
Authors: 
Antolak H, Kregiel D, Czyzowska A
Journal: 
J Food Prot 78(6):1186-90
Abstract: 

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.

Antioxidant Activity and Polyphenol Content of Cranberries (Vaccinium Macrocarpon).

Posted: 
March 23, 2016
Authors: 
Kalin P, Gulcin I, Goren AC
Journal: 
Rec Nat Prod 9(4):496-502
Abstract: 

Cranberries (Vaccinium macrocarpon) contain many bioactive compounds and have some biological activities and beneficial health properties. In the study, antioxidant effects of lyophilized aqueous extract of cranberry (LAEC) and quantity of some its polyphenolic compounds were determined. For this purpose, we performed DPPH., DMPD.+, ABTS.+ and O2.- radicals scavenging activities, inhibition of lipid peroxidation activity by thiocyanate method, Cu2+ and Fe3+ reducing abilities, FRAP assay and Fe2+ binding activity. At the 10 micro g/mL concentration, LAEC inhibited 52.4% lipid peroxidation produced by linoleic acid emulsion. Also, alpha -tocopherol, BHA, trolox, and BHT had 52.5, 89.9, 93.1 and 94.9% inhibition value at 30 micro g/mL concentration, respectively. Quantitative amounts of some phenolic compounds in LAEC were investigated by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). p-Hydroxy benzoic acid was found as the most abundant phenolic compound (55 mg/kg extract) in LAEC.

Cranberry Flavonoids Modulate Cariogenic Properties of Mixed-Species Biofilm through Exopolysaccharides-Matrix Disruption

Posted: 
March 23, 2016
Authors: 
Kim D, Hwang G, Liu Y, Wang Y, Singh AP, Vorsa N, Koo H
Journal: 
PLoS ONE 10(12):e0145844
Abstract: 

The exopolysaccharides (EPS) produced by Streptococcus mutans-derived glucosyltransferases (Gtfs) are essential virulence factors associated with the initiation of cariogenic biofilms. EPS forms the core of the biofilm matrix-scaffold, providing mechanical stability while facilitating the creation of localized acidic microenvironments. Cranberry flavonoids, such as A-type proanthocyanidins (PACs) and myricetin, have been shown to inhibit the activity of Gtfs and EPS-mediated bacterial adhesion without killing the organisms. Here, we investigated whether a combination of cranberry flavonoids disrupts EPS accumulation and S. mutans survival using a mixed-species biofilm model under cariogenic conditions. We also assessed the impact of cranberry flavonoids on mechanical stability and the in situ pH at the biofilm-apatite interface. Topical application of an optimized combination of PACs oligomers (100-300 muM) with myricetin (2 mM) twice daily was used to simulate treatment regimen experienced clinically. Treatments with cranberry flavonoids effectively reduced the insoluble EPS content (>80% reduction vs. vehicle-control; p

Effect of Dried Powder Preparation Process on Polyphenolic Content and Antioxidant Capacity of Cranberry (Vaccinium macrocarpon L.).

Posted: 
March 23, 2016
Authors: 
Oszmianski J, Kolniak-Ostek J, Lachowicz S, Gorzelany J, Matlok N
Journal: 
Ind Crop Prod 77:658-665.
Abstract: 

The aim of the study was to evaluate the effect of the degree of fragmentation of cranberry fruit (Vaccinium macrocarpon L.) on the chemical composition and antioxidant activity of fruit powders and lyophilized pomace and juices. In analyzed samples, the basic chemical composition, total polyphenolics and antioxidant capacity were determined. Thirty-nine polyphenolic compounds, including 9 phenolic acids, 7 anthocyanins, 9 flavan-3-ols and 14 flavonols, were identified. Polyphenolic concentrations in pomaces ranged from 16 038.74 mg/100 g DW in samples from whole fruits to 17 802.52 mg/100 g DW in samples from crushed fruits. In juices, phenolic concentrations ranged from 873.12 mg/100 g DW in products from whole fruits to 3177.87 mg/100 g DW in products from crushed fruits. Antioxidant capacities were higher in dry products than in juices. The highest DPPH, ABTS and FRAP values were determined in dry pomaces obtained from crushed fruits (156.94, 275.22 and 71.47 micro mol/g DW, respectively).

Nano-Liquid Chromatography Coupled to Time-of-Flight Mass Spectrometry for Phenolic Profiling: a Case Study in Cranberry Syrups

Posted: 
March 23, 2016
Authors: 
Contreras Mdel M, Arraez-Roman D, Fernandez-Gutierrez A, Segura-Carretero A
Journal: 
Talanta 132:929-38
Abstract: 

A new method based on nano-liquid chromatography coupled to time-of-flight mass spectrometry (nano-LC-TOF-MS) using lock-mass calibration was developed to facilitate the accurate and routine characterization and quantification of phenolic compounds. Thus, it was applied to study cranberry syrups, in which, using negative ionization mode, a total of nine phenolic compounds were unequivocally identified using standards and 38 tentatively taking into account their retention time, accurate mass (errors

Characterization and comparison of phenolic composition, antioxidant capacity and instrumental taste profile of juices from different botanical origins

Posted: 
September 28, 2015
Authors: 
Granato D, Karnopp AR, van Ruth SM
Journal: 
J Sci Food Agric 95(10):1997-2006
Abstract: 

BACKGROUND: The European Union registered a consumption of about 10.7 billion litres of juices in 2011 and a great part of this amount is imported from other countries, which makes the monitoring of their quality essential. This work was aimed at mapping the quality of various juices from different botanical origins from instrumental taste, chemical marker and antioxidant capacity perspectives. It also characterized the individual phenolic composition of juices previously classified according to their antioxidant activity and total phenolic material level.
RESULTS: Overall, by using correlation analysis and chemometrics (HCA and PCA), data showed that total phenolics, specifically gallic acid, p-coumaric acid, anthocyanins, flavanols and flavonols, are the main contributors to the antioxidant activity. Elderberry and pomegranate juices presented the highest phenolic content and antioxidant activity. On the other hand, orange, apple and cranberry juices had the lowest levels of total phenolics and flavonoids, DPPH and CUPRAC.
CONCLUSION: The use of chemometrics coupled to ANOVA seems to be a suitable approach to evaluate the quality of fruit juices from different botanical origins. Additionally, the instrumental taste profile correlated well with the chemical composition and antioxidant capacity, showing its potential application in assessing the functionality of juices.

Chemical characterization and chemo-protective activity of cranberry phenolic powders in a model cell culture. Response of the antioxidant defenses and regulation of signaling pathways

Posted: 
September 28, 2015
Journal: 
Food Res Int 71:68-82
Abstract: 

Oxidative stress and reactive oxygen species (ROS)-mediated cell damage are implicated in various chronic pathologies. Emerging studies show that polyphenols may act by increasing endogenous antioxidant defense potential. Cranberry has one of the highest polyphenol content among commonly consumed fruits. In this study, the hepato-protective activity of a cranberry juice (CJ) and cranberry extract (CE) powders against oxidative stress was screened using HepG2 cells, looking at ROS production, intracellular non-enzymatic and enzymatic antioxidant defenses by reduced glutathione concentration (GSH), glutathione peroxidase (GPx) and glutathione reductase (GR) activity and lipid peroxidation biomarker malondialdehyde (MDA). Involvement of major protein kinase signaling pathways was also evaluated. Both powders in basal conditions did not affect cell viability but decreased ROS production and increased GPx activity, conditions that may place the cells in favorable conditions against oxidative stress. Powder pre-treatment of HepG2 cells for 20 h significantly reduced cell damage induced by 400 micro M tert-butylhydroperoxide (t-BOOH) for 2 h. Both powders (5-50 micro g/ml) reduced t-BOOH-induced increase of MDA by 20% (CJ) and 25% (CE), and significantly reduced over-activated GPx and GR. CE, with a significantly higher amount of polyphenols than CJ, prevented a reduction in GSH and significantly reduced ROS production. CJ reversed the t-BOOH-induced increase in phospho-c-Jun N-terminal kinase. This study demonstrates that cranberry polyphenols may help protect liver cells against oxidative insult by modulating GSH concentration, ROS and MDA generation, antioxidant enzyme activity and cell signaling pathways.

Cranberries (Oxycoccus quadripetalus) inhibit lipid metabolism and modulate leptin and adiponectin secretion in 3T3-L1 adipocytes

Posted: 
September 28, 2015
Authors: 
Kowalska K, Olejnik A, Rychlik J, Grajek W
Journal: 
Food Chem 185:383-8
Abstract: 

It has previously been shown that lyophilized cranberries (LCB) decreased lipid accumulation in 3T3-L1 cells and inhibited preadipocyte differentiation by down-regulation of the expression of key transcription factors (PPARgamma, C/EBPalpha, SREBP1) of the adipogenesis pathway. To elucidate the molecular basis of anti-lipogenic activity of LCB, the expression of several genes involved in lipid metabolism, such as adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL), fatty acid synthase (FAS), hormone sensitive lipase (HSL) and perilipin 1 (PLIN1), was examined in the present study. Additionally, the effects of LCB on adiponectin and leptin expression and protein secretion were also investigated. LCB reduced lipid accumulation during preadipocyte differentiation by down-regulation of the mRNA level of aP2, FAS, LPL, HSL and PLIN1. Moreover, LCB decreased leptin gene expression and increased adiponectin gene expression and protein secretion in a dose-dependent manner. Therefore cranberries could be considered as bioactive factors, which are effective in the inhibition of adipose tissue mass production.

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