Effect of cranberry juice concentrate on chemically-induced urinary bladder cancers.

The chemopreventive efficacy of cranberry juice concentrate in an experimental model of urinary bladder cancer was evaluated using female Fischer-344 rats. The animals received N-butyl-N-(4-hydroxybutyl)-nitrosamine (OH-BBN) for a period of eight weeks. Cranberry juice concentrate was administered at doses of 1.0 or 0.5 ml/rat/day beginning one week after the final OH-BBN treatment and continuing until the end of the study. The urinary bladders of all the rats were weighed and examined grossly for lesions, and all masses were submitted for pathological evaluation. A dose-dependent preventive effect of cranberry treatment was observed, with a reduced number of urinary bladder cancers (38%) in the 1.0 ml/rat/day group versus the control group. The cranberry extract neither affected body weight gain nor caused other signs of toxicity. For the metabolic studies, serum and urine were collected at 4 and 12 h after the administration of the cranberry juice concentrate and were analyzed by LC-MS/MS. Quercetin and its methylated derivative were detected in the urine samples. However, no quercetin was detected in the serum samples, indicating its poor bioavailability. These data suggest that components of cranberries may be effective in preventing urinary bladder carcinogenesis.

Constituyentes fitoquímicos del arándano americano (Vaccinium macrocarpon) y sus beneficios para la salud / No disponible

While cranberries (fruit of Vaccinium macrocarpon Ait.) and fruits in general provide many nutritional and health promoting qualities, due to their unique proanthocyanidin (PAC) composition, cranberries al so provide an additional benefit in the form of bacterial anti-adhesion activity. This activity is being seen to have an important impact on urinary tract health, and may impact other health states where bacterial adhesion is part of the disease mechanism. Continued research on the nutritional and healthful components of cranberries will be challenging. Analytically, lack of standards makes it difficult to quantify some of these components for determining how they vary and how they may be affected by processing. Improved methods are also needed to analyze the complex fractions derived from bioassay directed fractionation. Biologically, there is a need to better understand how these components are absorbed and metabolized for determining the mechanisms involved and so markers can be identified that allow for improved monitoring of clinical study compliance

Las frutas en general tienen un valor nutricional y un efecto potenciador de la salud. El arándano americano (fruto de Vaccinium macrocarpon Ait.), debido a su composición en proantocianidinas (PAC), proporciona un beneficio adicional gracias a su actividad inhibidora de la adherencia bacteriana, por lo que puede tener un efecto beneficioso en determinadas afecciones bacterianas. Desde el punto de vista analítico, la falta de sustancias de referencia dificulta la cuantificación de algunos de los componentes del arándano americano para determinar su variabilidad y cómo se pueden ver afectados por el procesamiento. Asimismo, se necesitan métodos mejorados para analizar las complejas fracciones derivadas del fraccionamiento biodirigido. Desde el punto de vista biológico, existe la necesidad de comprender mejor la forma en que estos componentes se absorben y se metabolizan para determinar los mecanismos implicados y poder identificar los marcadores que permitan una mejor supervisión del seguimiento de los estudios clínicos

An LC-MS method for analyzing total resveratrol in grape juice, cranberry juice, and in wine.

Resveratrol is an antioxidant found in grapes, grape products, and some other botanical sources with antiinflammatory and anticancer properties. In grapes and wine, it occurs both as free resveratrol and piceid, the 3beta-glucoside of resveratrol. Here we report a liquid chromatography-mass spectrometry method to analyze total resveratrol (including free resveratrol and resveratrol from piceid) in fruit products and wine. Samples were extracted using methanol, enzymatically hydrolyzed, and analyzed using reversed phase HPLC with positive ion atmospheric pressure chemical ionization (APCI) mass spectrometric detection. Following APCI, the abundance of protonated molecules was recorded using selected ion monitoring (SIM) of m/z 229. An external standard curve was used for quantitation, which showed a linear range of 0.52-2260 pmol of trans-resveratrol injected on-column with a correlation coefficient 0.9999. The coefficient of variance of the response factor over the same concentration range was determined to be 5.8%, and the intra-assay coefficient of variance was determined to be 4.2% (n = 7). The limit of quantitation, defined as signal-to-noise 10:1, was determined to be 0.31 pmol injected on-column. The extraction efficiency of the method was determined to be 92%. The stability of resveratrol under different conditions was also examined. For example, resveratrol was stable for up to 5 days at 4 degrees C in the dark but was not stable at room temperature without protection from light. Resveratrol was detected in grape, cranberry, and wine samples. Concentrations ranged from 1.56 to 1042 nmol/g in Concord grape products, and from 8.63 to 24.84 micromol/L in Italian red wine. The concentrations of resveratrol were silmilar in cranberry and grape juice at 1.07 and 1.56 nmol/g, respectively.