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2014

Displaying 41 - 45 of 45

Quantification by UHPLC of total individual polyphenols in fruit juices.

Posted: 
February 15, 2014
Authors: 
Diaz-Garcia MC, Obon JM, Castellar MR, Collado J, Alacid M
Journal: 
Food Chem 138(2-3):938-49
Abstract: 

The present work proposes a new UHPLC-PDA-fluorescence method able to identify and quantify the main polyphenols present in commercial fruit juices in a 28-min chromatogram. The proposed method improve the IFU method No. 71 used to evaluate anthocyanins profiles of fruit juices. Fruit juices of strawberry, American cranberry, bilberry, sour cherry, black grape, orange, and apple, were analysed identifying 70 of their main polyphenols (23 anthocyanins, 15 flavonols, 6 hydroxybenzoic acids, 14 hydroxycinnamic acids, 4 flavanones, 2 dihydrochalcones, 4 flavan-3-ols and 2 stilbenes). One standard polyphenol of each group was used to calculate individual polyphenol concentration presents in a juice. Total amount of polyphenols in a fruit juice was estimated as total individual polyphenols (TIP). A good correlation (r(2)=0.966) was observed between calculated TIP, and total polyphenols (TP) determined by the well-known colorimetric Folin-Ciocalteu method. In this work, the higher TIP value corresponded to bilberry juice (607.324 mg/100mL fruit juice) and the lower to orange juice (32.638 mg/100mL fruit juice). This method is useful for authentication analyses and for labelling total polyphenols contents of commercial fruit juices. Copyright 2012 Elsevier Ltd. All rights reserved.

Quantifying and characterizing proanthocyanidins in cranberries in relation to urinary tract health. [Review]

Posted: 
February 15, 2014
Authors: 
Krueger CG, Reed JD, Feliciano RP Howell AB
Journal: 
Anal Bioanal Chem 405(13):4385-95
Abstract: 

The "A-type" proanthocyanidins in cranberry fruit (Vaccinium macrocarpon Ait.) are bioactive components associated with prevention of urinary tract infections (UTI). Cranberry juice, fruit (fresh and dried), functional foods, and cranberry dietary supplements are promoted for prevention of UTI and for maintenance of urinary tract health (UTH), on the basis of their content of cranberry proanthocyanidins (c-PAC) with "A-type" interflavan bonds. With increasing consumer use of cranberries for maintenance of UTH and an expanding number of commercial cranberry products of different types, the availability of unified methods for measuring levels of c-PAC is important. This review discusses quantitative and qualitative analysis of c-PAC with "A-type" interflavan bonds in relation to their biological activity for UTI prevention. The integrity (including authenticity, standardization, efficacy, and safety) of cranberry fruit, juices, and dietary supplements may now be measured by using recent advances in mass spectrometry, liquid chromatography, production of c-PAC standards, and improved simple quantitative techniques.

Relationship between polyphenol content and anti-influenza viral effects of berries.

Posted: 
February 15, 2014
Authors: 
Sekizawa H, Ikuta K, Mizuta K, Takechi S, Suzutani T
Journal: 
J Sci Food Agric 93(9):2239-41
Abstract: 

BACKGROUND: Berries are known to have many kinds of biological activities. We focused on their antiviral effect, which has not yet been well evaluated.

RESULTS: We compared the anti-influenza viral effects of berries belonging to the genus Vaccinium - 35 species of blueberry (Vaccinium cyanococcus), the Natsuhaze (Vaccinium oldhamii), bilberry (Vaccinium myrtillus) and cranberry (Vaccinium oxycoccos)- with those belonging to the genus Ribes, i.e. blackcurrant (Ribes nigrum). Only Elliott and Legacy among Northern Highbush varieties but many Rabbiteye varieties such as Austin, Baldwin, Brightblue, Festival, T-100 and Tifblue showed anti-influenza viral activity. Natsuhaze, bilberry, cranberry and blackcurrant had high antiviral effects. A relationship was observed between the antiviral effect and total polyphenol content.

CONCLUSIONS: Antiviral effects were found to differ markedly between berry species. Rabbiteye varieties tended to have higher antiviral effects than Northern, Southern and Half Highbush blueberry varieties. We also found that Natsuhaze, which has recently been harvested in Japan as a potential functional food, had an antiviral effect comparable to that of bilberry, cranberry and blackcurrant. There was a positive relationship between antiviral activity and polyphenol content, indicating the possibility that polyphenol is one of the key factors in the antiviral effects of berries. 2012 Society of Chemical Industry.

The longevity effect of cranberry extract in Caenorhabditis elegans is modulated by daf-16 and osr-1.

Posted: 
February 15, 2014
Authors: 
Guha S, Cao M, Kane RM, Savino AM, Zou S, Dong Y
Journal: 
Age 35(5):1559-74
Abstract: 

Nutraceuticals are known to have numerous health and disease preventing properties. Recent studies suggest that extracts containing cranberry may have anti-aging benefits. However, little is known about whether and how cranberry by itself promotes longevity and healthspan in any organism. Here we examined the effect of a cranberry only extract on lifespan and healthspan in Caenorhabditis elegans. Supplementation of the diet with cranberry extract (CBE) increased the lifespan in C. elegans in a concentration-dependent manner. Cranberry also increased tolerance of C. elegans to heat shock, but not to oxidative stress or ultraviolet irradiation. In addition, we tested the effect of cranberry on brood size and motility and found that cranberry did not influence these behaviors. Our mechanistic studies indicated that lifespan extension induced by CBE requires the insulin/IGF signaling pathway and DAF-16. We also found that cranberry promotes longevity through osmotic stress resistant-1 (OSR-1) and one of its downstream effectors, UNC-43, but not through SEK-1, a component of the p38 MAP kinase pathway. However, SIR-2.1 and JNK signaling pathways are not required for cranberry to promote longevity. Our findings suggest that cranberry supplementation confers increased longevity and stress resistance in C. elegans through pathways modulated by daf-16 and osr-1. This study reveals the anti-aging property of widely consumed cranberry and elucidates the underpinning mechanisms.

Urine post equivalent daily cranberry juice consumption may opsonize uropathogenicity of Escherichia coli.

Posted: 
February 15, 2014
Authors: 
Chen CS, Ho DR, Chang PJ, Lin WY, Huang YC
Journal: 
J Infect Chemother 19(5):812-7
Abstract: 

Basic studies have proven that cranberries may prevent urinary tract infections through changing the adhesiveness of Escherichia coli (E. coli) to urothelial cells. Various cranberry preparations, including extract powder, capsules, and juice, have been shown to be effective in clinical and epidemiological research. Because cranberries are most commonly consumed as juice in a diluted concentration, the aim of this study was to investigate whether the equivalent daily dose of cranberry juice is sufficient to modify host urine to change the uropathogenicity of E. coli. Urine from rats taking an equivalent daily dose of cranberry juice has been shown to decrease the capability of E. coli in hemagglutination, urothelium adhesion, nematode killing, and biofilm formation. All these changes occurred after E. coli was incubated in cranberry metabolite-containing urine, defined as urine opsonization. Urine opsonization of E. coli resulted in 40.9% (p = 0.0038) decrease in hemagglutination ability, 66.7% (p = 0.0181) decrease in urothelium adhesiveness, 16.7% (p = 0.0004) increase in the 50% lethal time in killing nematodes, and 53.9% (p = 5.9 x 10(-4)) decrease in biofilm formation. Thus, an equivalent daily dose of cranberry juice should be considered sufficiently potent to demonstrate urine opsonization in E. coli.

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