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1.
Phytother Res ; 28(3): 465-70, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23922238

ABSTRACT

Cranberries exert a dose-dependent inhibition of the adherence of E. coli fimbriae to uroepithelial cells. This was demonstrated in vitro but also ex vivo in vitro with urine from cranberry consumers. The active principle has not been identified in detail but type-A proanthocyanidins (PAC) play an important role in the mechanism of action. Since the three species, American cranberry (Vaccinium macrocarpon), European cranberry (Vaccinium oxycoccus) and/or lingonberry (Vaccinium vitis-idaea), have different patterns of type-A PACs, results from one species cannot be transferred to the others. It seems likely that most of the studies with monopreparations from V. macrocarpon were underdosed. Whereas photometric PAC quantification may overestimate the true content on co-active compounds, reversed phase high-performance liquid chromatograpy may underestimate them. Recent studies with PAC doses in the upper range (DMAC method) or declared type-A PAC content in the daily dose reveal a dose-dependent trend of clinical effectiveness, however, with a possible ceiling effect. In order to clarify this, future three-arm studies should investigate Vaccinium preparations with higher type-A PAC doses than previously used. We analysed two popular European vitis-idaea products, a mother juice and a proprietary extract. Both preparations may be appropriate to confirm the Vaccinium urinary tract infection-preventive effect beyond doubt.


Subject(s)
Plant Extracts/pharmacology , Proanthocyanidins/pharmacology , Urinary Tract Infections/prevention & control , Vaccinium/chemistry , Escherichia coli/drug effects , Fruit/chemistry , Humans , Urinary Tract Infections/drug therapy , Vaccinium macrocarpon/chemistry , Vaccinium vitis-idaea/chemistry
2.
J Agric Food Chem ; 60(45): 11292-300, 2012 Nov 14.
Article in English | MEDLINE | ID: mdl-23072538

ABSTRACT

Exotic fruits such as açai, camu-camu, and blackberries rich in natural antioxidants (ascorbic acid, anthocyanins) are marketed as "functional" foods supporting a pro-/antioxidant balance. Confirming data from human studies are lacking. Within a randomized controlled crossover trial, 12 healthy nonsmokers ingested 400 mL of a blended juice of these fruits or a sugar solution (control). Blood was drawn before and afterward to determine antioxidants in plasma, markers of antioxidant capacity [trolox equivalent antioxidant capacity, Folin-Ciocalteu reducing capacity, total oxidant scavenging capacity (TOSC)] and oxidative stress [isoprostane, DNA strand breaks in leukocytes in vivo], and their resistance versus H2O2-induced strand breaks. Compared with sugar solution, juice consumption increased plasma ascorbic acid and maintained TOSC and partly Folin-Ciocalteu reducing capacity (both P values < 0.05). Strand breaks in vivo increased after ingestion of both beverages (P < 0.001), probably due to postprandial and/or circadian effects. This anthocyanin-rich fruit juice may stabilize the pro-/antioxidant balance in healthy nonsmokers without affecting markers of oxidative stress.


Subject(s)
Anthocyanins/metabolism , Antioxidants/metabolism , Ascorbic Acid/metabolism , Beverages/analysis , Biomarkers/analysis , Fruit/chemistry , Functional Food/analysis , Plant Extracts/metabolism , Adolescent , Adult , Anthocyanins/analysis , Antioxidants/analysis , Ascorbic Acid/analysis , Biomarkers/metabolism , Female , Fruit/metabolism , Humans , Male , Middle Aged , Oxidative Stress , Plant Extracts/analysis , Young Adult
3.
J Agric Food Chem ; 60(38): 9688-96, 2012 Sep 26.
Article in English | MEDLINE | ID: mdl-22931094

ABSTRACT

Cranberry procyanidins have been associated with an effect against urinary tract infections (UTI) for decades, and European health claims are requested. This study compares the procyanidin profiles and concentrations of American cranberry ( Vaccinium macrocarpon Ait.), European cranberry ( Vaccinium oxycoccus L.), and lingonberry ( Vaccinium vitis-idaea L.) analyzed using ultrahigh-performance liquid chromatoraphy coupled to a triple-quadrupole mass spectrometer with electrospray interface (UHPLC-MS(2)). Concentrations of A-type trimers, procyanidin A2, catechin, epicatechin, and B-type dimers and trimers have been evaluated and compared for the first time in the three berries. The data clearly show remarkable differences in the procyanidin profiles and concentrations, especially the lack of A-type trimers in V. oxycoccus; thus, the effectiveness against UTI may vary among the Vaccinium species. These differences can be used to prove authenticity.


Subject(s)
Proanthocyanidins/analysis , Vaccinium/chemistry , Catechin/analysis , Chromatography, High Pressure Liquid/methods , Dimerization , Flavonoids/analysis , Food Analysis/methods , Fruit/chemistry , Humans , Mass Spectrometry/instrumentation , Mass Spectrometry/methods , Species Specificity , Urinary Tract Infections/diet therapy , Vaccinium macrocarpon/chemistry , Vaccinium vitis-idaea/chemistry
4.
J Agric Food Chem ; 59(14): 7688-99, 2011 Jul 27.
Article in English | MEDLINE | ID: mdl-21662239

ABSTRACT

The Amazon region comprises a plethora of fruit-bearing species of which a large number are still agriculturally unimportant. Because fruit consumption has been attributed to an enhanced physical well-being, interest in the knowledge of the chemical composition of underexplored exotic fruits has increased during recent years. This paper provides a comprehensive identification of the polyphenolic constituents of four underutilized fruits from the Amazon region by HPLC/DAD-ESI-MS(n). Araçá ( Psidium guineense ), jambolão ( Syzygium cumini ), muruci ( Byrsonima crassifolia ), and cutite ( Pouteria macrophylla ) turned out to be primarily good sources of hydrolyzable tannins and/or flavonols. Additionally, different flavanonols and proanthocyanidins were identified in some fruits. The antioxidant capacity was determined by using the total oxidant scavenging capacity (TOSC) assay. Cutite showed the highest antioxidant capacity followed by jambolão, araçá, and muruci.


Subject(s)
Antioxidants/analysis , Flavonoids/analysis , Fruit/chemistry , Magnoliopsida/chemistry , Phenols/analysis , Plant Extracts/analysis , Brazil , Polyphenols , Spectrometry, Mass, Electrospray Ionization
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