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Determination of Anthocyanins in Cherry and Cranberry by High-Performance Liquid Chromatography–Electrospray Lonization–Mass Spectrometry

Posted: 
March 1, 2017
Authors: 
Karaaslan NM, Yaman M
Journal: 
Eur Food Res Technol (2016) 242: 127
Abstract: 

Anthocyanins are a group of widespread natural phenolic compounds in vegetables and fruits. The anthocyanins have a wide range of applications due to the antioxidant, anticancer and anti-inflammatory properties. In this study, anthocyanins (delphinidin-3-o-glucoside, cyanidin-3-o-glucoside, pelargonidin-3-o-glucoside and malvidin-3-o-glucoside) in cherry and cranberry were determined using high-performance liquid chromatography–electrospray ionization–mass spectrometry (HPLC–ESI–MS). The anthocyanins were separated using gradient elution and a reserved-phase analytical column before identification by high-performance liquid chromatography–electrospray ionization–mass spectrometry. A high-performance liquid chromatography–electrospray ionization–mass spectrometry method was optimized for the determination of anthocyanins in cherry and cranberry. Furthermore, in this study, we investigated extraction conditions of fruit samples as well as determination of optimum HPLC–ESI–MS conditions. This study is novel in terms of simultaneously examining both optimization of HPLC parameters and extraction conditions. Obtained optimum conditions were used for the determination as the quantitative and qualitative analysis of anthocyanins in cherry and cranberry. The content of anthocyanins on the basis of wet weight in cherry and cranberry samples was determined for delphinidin-3-o-glucoside

Study of the Impact of Cranberry Extract on the Virulence Factors and Biofilm Formation by Enterococcus Faecalis Strains Isolated from Urinary Tract Infections

Posted: 
March 1, 2017
Authors: 
Wojnicz D, Tichaczek-Goska D, Korzekwa K, Kicia M, Hendrich AB
Journal: 
Int J Food Sci Nutr 67(8):1005-16
Abstract: 

Drinking of cranberry fruit juice and application of commercial preparations containing the cranberry extracts are recommended in the prevention and treatment of urinary tract infections (UTIs), especially in women with recurrent UTIs. Many studies focus on the activity of cranberries against uropathogenic Escherichia coli (E. coli) strains. However, the knowledge of the cranberry effect on Gram-positive Enterococcus faecalis (E. faecalis) is limited. Therefore, the aim of our study was to establish the activity of commercial concentrated cranberry extract on the growth, virulence factors and biofilm formation of E. faecalis strains isolated from urine. Minimal inhibitory concentrations (MICs) of cranberry extract were determined by the broth microdilution method. Disc diffusion method was used to determine antimicrobial susceptibility. The impact of cranberry extract on bacterial survival, hydrophobicity, synthesis of lipase, lecithinase, DNase, hemolysin, gelatinase and biofilm mass was determined. Results show that cranberry extract inhibits the growth, enzymatic activities of bacteria and limits biofilm formation. The antibacterial activities of the studied cranberry extract confirm that it could be successfully used in prevention of UTIs caused by E. faecalis.

Ultrahigh Pressure Liquid Chromatography-Atmospheric Pressure Photoionization-Tandem Mass Spectrometry for the Determination of Polyphenolic Profiles in the Characterization and Classification of Cranberry-Based Pharmaceutical preparations and natural ext

Posted: 
March 1, 2017
Authors: 
Parets L, Alechaga E, Nunez O, Saurina J, Hernandez-Cassou S, Puignou L
Journal: 
Anal Methods 8(22):4363-4378
Abstract: 

Ultrahigh pressure liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry (UHPLC-APPI-MS/MS) was applied to the analysis and authentication of fruit-based products and pharmaceutical preparations. Two sub-2 micro m C18 reversed-phase columns, Syncronis (100x2.1 mm, 1.7 micro m) and Hypersil Gold (50x2.1 mm, 1.9 micro m), were proposed under gradient elution with 0.1% formic acid aqueous solution and methanol mobile phases for the determination of 29 polyphenols, allowing us to obtain polyphenolic profiles in less than 13.5 and 23.5 min, respectively. Several atmospheric pressure ionization (API) sources (H-ESI, APCI, and APPI) were compared. For dopant-assisted APPI, four organic solvents, toluene, acetone, chlorobenzene and anisole, were evaluated as dopants. Both H-ESI and acetone-assisted APPI were selected as the best ionization sources for the analysis of targeted polyphenols. Acceptable sensitivity (LOD values down to 0.5 micro g kg-1 in the best of cases), linearity (r2 higher than 0.995) and good precision (RSD values lower than 15.1%) and trueness (relative errors lower than 10.2%) were obtained using both UHPLC-API-MS/MS methods. A simple extraction procedure, consisting of sample sonication with acetone/water/hydrochloric acid (70:29.9:0.1 v/v/v) and centrifugation, was used. The proposed UHPLC-ESI-MS/MS and UHPLC-APPI-MS/MS methods with both C18 reversed-phase columns were then applied to the analysis of 32 grape-based and cranberry-based natural products and pharmaceutical preparations. Polyphenolic profile data were then analyzed by principal component analysis (PCA) to extract information on the most significant data contributing to the classification of natural extracts according to the type of fruit.

Urinary Clearance of Cranberry Flavonol Glycosides in Humans 2

Posted: 
March 1, 2017
Authors: 
Wang Y, Singh AP, Nelson HN, Kaiser AJ, Reker NC, Hooks TL, Wilson T, Vorsa N.
Journal: 
J Agric Food Chem 64(42):7931-7939
Abstract: 

Cranberry is reported to have health benefits, including prevention of urinary tract infections and other chronic diseases, due to the high content of polyphenols, including flavonols and flavan-3-ols. The aim of this study was to determine the clearance of flavonol glycosides and flavan-3-ols and/or their metabolites in human urine. Ten healthy women volunteers ingested 240 mL of cranberry juice containing flavonol glycosides. Urine samples were collected at 0, 90, 225, and 360 min postingestion. While flavan-3-ols were not detected, five flavonol glycosides common in cranberry were identified. Quercetin-3-galactoside, the most abundant cranberry flavonol, exhibited the highest peak urine concentration (Cmax) of 1315 pg/mg creatinine, followed by quercetin-3-rhamnoside, quercetin-3-arabinoside, myricetin-3-arabinoside, and myricetin-3-galactoside. Quercetin-3-arabinoside showed delayed clearance, Cmax at 237 min (Tmax), relative to other flavonols (90-151 min). Both aglycone and the conjugated sugar moiety structure mediate the flavonol's bioavailability. Interindividual variation for bioavailability and clearance is also apparent. Metabolites, e.g. glucoronides, were not detected.

Adjuvant effect of cranberry proanthocyanidin active fraction on antivirulent property of ciprofloxacin against Pseudomonas aeruginosa.

Posted: 
August 22, 2016
Authors: 
Vadekeetil A., Alexandar V., Chhibber S., Harjai K.
Journal: 
Microbial Pathogenesis; 2016. 90:98-103
Abstract: 

Quorum sensing inhibitors (QSIs) act as antivirulent agents since quorum sensing (QS) plays a vital role in regulating pathogenesis of Pseudomonas aeruginosa. However, application of single QSI may not be effective as pathogen is vulnerable to successful mutations. In such conditions, combination of QSIs can be exploited as there can be synergistic or adjuvant action. In the present study, we evaluated the antivirulence efficacy of combination of Vaccinium macrocarpon proanthocyanidin active fraction (PAF) and ciprofloxacin (CIP) at their sub-MICs using standard methods followed by analysis of their mode of action on QS using TLC and molecular docking. There was significant improvement in action of CIP when it was combined with PAF in reducing the QS controlled virulence factors (p<0.05), motilities and biofilm of P. aeruginosa. TLC profiles of QS signals [(Acyl homoserine lactone (AHL) and Pseudomonas quinolone signal (PQS))] indicated that CIP in combination with PAF, besides showing inhibitory action on production of AHLs, also modulated production and inactivation of PQS. Docking scores also supported the observation. We therefore hypothesize that PAF-CIP combination, having improved anti-virulence property; can be exploited as a potent drug pairing against P. aeruginosa.

Antibacterial activity of isolated phenolic compounds from cranberry (Vaccinium macrocarpon) against Escherichia coli.

Posted: 
August 22, 2016
Authors: 
Rodriguez-Perez, C. Quirantes-Pine, R. Uberos, J. Jimenez-Sanchez, C. Pena, A. Segura-Carretero, A.
Journal: 
Food and Function; 2016. 7(3):1564-1573.
Abstract: 

Phenolic compounds from a cranberry extract were isolated in order to assess their contribution to the antibacterial activity against uropathogenic strains of Escherichia coli (UPEC). With this purpose, a total of 25 fractions from a cranberry extract were isolated using semipreparative high performance liquid chromatography (HPLC) and characterized based on the results obtained by reversed-phase HPLC coupled to mass spectrometry detection. Then, the effects on UPEC surface hydrophobicity and biofilm formation of the cranberry extract as well as the purest fractions (a total of 13) were tested. As expected, the whole extract presented a powerful antibacterial activity against UPEC while the selected fractions presented a different behavior. Myricetin and quercitrin significantly decreased (p <0.05) E. coli biofilm formation compared with the control, while dihydroferulic acid glucuronide, procyanidin A dimer, quercetin glucoside, myricetin and prodelphinidin B led to a significant decrease of the surface hydrophobicity compared with the control. The results suggest that apart from proanthocyanidins, other compounds, mainly flavonoids, can act against E. coli biofilm formation and also modify UPEC surface hydrophobicity in vitro, one of the first steps of adhesion.

Beneficial effects of cranberry in the prevention of obesity and related complications: metabolic syndrome and diabetes - a review.

Posted: 
August 22, 2016
Authors: 
Kowalska, K. Olejnik, A.
Journal: 
Journal of Functional Foods; 2016. 20:171-181
Abstract: 

In recent years, obesity, metabolic syndrome and diabetes are becoming epidemic both in developed and developing countries. Recent experimental and clinical studies have raised interest in the potential health benefits of cranberry consumption in obesity and metabolic syndrome, which appear to be associated with the phytochemical composition of this fruit. Interestingly, cranberry administration has been reported to ameliorate dyslipidemia, hyperglycaemia and oxidative stress in individuals with the metabolic syndrome. This review focuses on the recent findings regarding beneficial effects of cranberry on obesity and metabolic syndrome, and discusses its potential mechanisms of action. The results of studies presented in this review have demonstrated that cranberry ameliorates insulin resistance and plasma lipid profile, decreases diet-induced weight gain and visceral obesity, and diminishes blood markers of oxidative stress. Thus, cranberry could be an effective and safe component of functional foods addressed for individuals with metabolic complications.

Cranberries (Oxycoccus quadripetalus) inhibit pro-inflammatory cytokine and chemokine expression in 3T3-L1 adipocytes.

Posted: 
August 22, 2016
Authors: 
Kowalska K., Olejnik A
Journal: 
Food chemistry. 196 (pp 1137-1143), 2016
Abstract: 

Oxidative stress and inflammation are involved in the development of obesity, type 2 diabetes and vascular complications. Systemic inflammation, as seen in obesity, is associated with high plasmatic levels of pro-inflammatory, pro-atherogenic and pro-thrombotic adipokines. Here we studied the effects of lyophilized cranberries (LCB) on the secretion and expression of PAI-1, IL-6, MCP-1 and leptin in mature 3T3-L1 adipocytes under baseline conditions and excessive inflammatory response elicitation by stimulation with H2O2. Our data demonstrated that LCB significantly reduced the expression and secretion of IL-6, MCP-1 and leptin, as well as suppressed the overexpression of PAI-1 induced by H2O2. Our findings suggested that LCB counteracted the stimulatory effect of H2O2 on secretion and expression of pro-inflammatory adipokines, implying a potential anti-inflammatory effect during the inflammatory process induced via oxidative stress in adipose tissue.

Cranberry derivatives enhance biofilm formation and transiently impair swarming motility of the uropathogen Proteus mirabilis HI4320.

Posted: 
August 22, 2016
Authors: 
O'May, C. Amzallag, O. Bechir, K. Tufenkji, N.
Journal: 
Can J Microbiol; 2016. 62(6):464-474.
Abstract: 

Proteus mirabilis is a major cause of catheter-associated urinary tract infection (CAUTI), emphasizing that novel strategies for targeting this bacterium are needed. Potential targets are P. mirabilis surface-associated swarming motility and the propensity of these bacteria to form biofilms that may lead to catheter blockage. We previously showed that the addition of cranberry powder (CP) to lysogeny broth (LB) medium resulted in impaired P. mirabilis swarming motility over short time periods (up to 16 h). Herein, we significantly expanded on those findings by exploring (i) the effects of cranberry derivatives on biofilm formation of P. mirabilis, (ii) whether swarming inhibition occurred transiently or over longer periods more relevant to real infections (~3 days), (iii) whether swarming was also blocked by commercially available cranberry juices, (iv) whether CP or cranberry juices exhibited effects under natural urine conditions, and (v) the effects of cranberry on medium pH, which is an indirect indicator of urease activity. At short time scales (24 h), CP and commercially available pure cranberry juice impaired swarming motility and repelled actively swarming bacteria in LB medium. Over longer time periods more representative of infections (~3 days), the capacity of the cranberry material to impair swarming diminished and bacteria would start to migrate across the surface, albeit by exhibiting a different motility phenotype to the regular "bull's-eye" swarming phenotype of P. mirabilis. This bacterium did not swarm on urine agar or LB agar supplemented with urea, suggesting that any potential application of anti-swarming compounds may be better suited to settings external to the urine environment. Anti-swarming effects were confounded by the ability of cranberry products to enhance biofilm formation in both LB and urine conditions. These findings provide key insights into the long-term strategy of targeting P. mirabilis CAUTIs.

Cranberry proanthocyanidins modulate reactive oxygen species in Barrett's and esophageal adenocarcinoma cell lines.

Posted: 
August 22, 2016
Authors: 
Weh, K. M. Aiyer, H. S. Howell, A. B. Kresty, L. A.
Journal: 
Journal of Berry Research; 2016. 6(2):125-136.
Abstract: 

BACKGROUND: We recently reported that a cranberry proanthocyanidin rich extract (C-PAC) induces autophagic cell death in apoptotic resistant esophageal adenocarcinoma (EAC) cells and necrosis in autophagy resistant cells. EAC is characterized by high morbidity and mortality rates supporting development of improved preventive interventions. OBJECTIVE: The current investigation sought to investigate the role of reactive oxygen species (ROS) in the context of C-PAC induced cell death. METHODS: Apanel of human esophageal cell lines of EAC or BE (Barrett's esophagus) origin were treated with C-PAC and assessed for ROS modulation using CellROXReg. Green reagent and the Amplex Red assay to specifically measure hydrogen peroxide levels. RESULTS: C-PAC significantly increased ROS levels in EAC cells, but significantly reduced ROS levels in CP-C BE cells. Increased hydrogen peroxide levels were also detected in C-PAC treated EAC cells and supernatant; however, hydrogen peroxide levels were significantly increased in medium alone, without cells, suggesting that C-PAC interferes or directly acts on the substrate. Hydrogen peroxide levels did not change in C-PAC treated CP-C BE cells. CONCLUSION: These experiments provide additional mechanistic insight regarding C-PAC induced cancer cell death through modulation of ROS. Additional research is warranted to identify specific ROS species associated with C-PAC exposure.

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