New Insights into the Exploitation of Vitis vinifera L. cv. Aglianico Leaf Extracts for Nutraceutical Purposes.

The leaves of Vitis vinifera L. have been used for a long time in traditional medicine for the treatment of many ailments. Grape polyphenols, indeed, have been demonstrated to be able to defend against oxidative stress, responsible for various disorders such as cancer, diabetes and neurodegenerative diseases. The effects of different extraction techniques, Soxhlet (SOX), Accelerated Solvent (ASE 40, ASE 50) and Ultrasound Assisted Extraction (UAE) were studied in this work to evaluate their impact on the chemical profile and bioactive potential of Vitis vinifera L. (cv. Aglianico) leaf extracts. The phytochemical profile was investigated by HPLC-DAD and 9 phenolic compounds were identified and quantified in the extract. Moreover, the antioxidant, anticholinesterase and antityrosinase activities were evaluated. In detail, the total polyphenol content and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl, Oxygen Radical Absorbance Capacities and ß-Carotene Bleaching assays) were evaluated and compared to assess the Relative Antioxidant Capacity Index (RACI). To test the inhibitory activity of extracts towards cholinesterases, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition assays were performed. SOX and ASE 50 have shown the highest value of RACI, 0.76 and 0.65, respectively. Regarding enzymatic inhibitory activity, ASE 50 (IC50 = 107.16 ± 8.12 µg/mL) and SOX (IC50 = 171.34 ± 12.12 µg/mL) extracts exhibited the highest AChE and BChE inhibitory activity, respectively, while UAE (IC50 = 293.2 ± 25.6 µg/mL, followed by SOX (IC50 = 302.5 ± 38.3 µg/mL) showed the highest tyrosinase inhibition value. Our results demonstrated for the first time that Aglianico leaves are important sources of phenols that could be used to prevent oxidative stress and be potentially helpful in diseases treatable with tyrosinase and cholinesterase inhibitors, like myasthenia gravis or Alzheimer's.

Preharvest methyl jasmonate and postharvest UVC treatments: increasing stilbenes in wine.

UNLABELLED: Stilbene-enriched wine is considered to be an interesting new food product with added value due to its potential health-promoting properties. Stilbene concentration in grape is highly variable and rather scarce. However, it can be increased by stress treatments. For this reason, numerous pre- and postharvest grape treatments, and some combinations of them, have been tested to maximize stilbene content in grapes. In the present manuscript, Syrah grapes were treated with (i) methyl jasmonate (MEJA), (ii) ultraviolet light (UVC), and (iii) methyl jasmonate and ultraviolet light (MEJA-UVC) and compared with untreated grapes. Afterward, winemaking was developed. Wine achieved by combination of both treatments (MEJA-UVC) contained significantly higher stilbene concentration (trans-resveratrol and piceatannol) than its respective control (2.5-fold). Wine quality was improved in color-related parameters (color intensity, L*, a*, b*, ΔE*, anthocyanins, and tannin). Moreover, MEJA-UVC wines obtained the highest score in sensorial analysis. To the best of our knowledge, this is the first time that pre- and postharvest treatments are combined to increase stilbenes in wine. PRACTICAL APPLICATION: The effect of treatment combination (methyl jasmonate and UVC light) on grape and wine was evaluated. Our results highlight the positive effect of the treatments in stilbene content, color parameters, and sensorial analysis. Moreover, added-value by-products were achieved.

Isorhapontigenin: a novel bioactive stilbene from wine grapes.

Stilbenes are a family of bioactive compounds found in plants. However, only a few stilbenes are present in the human diet. Grape and wine are the main dietary source of stilbenes, resveratrol and piceid being the most common ones. Ultraviolet C light (UVC) postharvest treatment was used to obtain significantly increased stilbene concentration in grapes. A new, previously undescribed-in-grapes stilbene was found after UVC treatment. The process followed to isolate and identify this unknown stilbene is described in the present work. This isolation involved several fractionation steps including counter current chromatography and semi-preparative HPLC due to its low concentration and the presence of structurally related compounds. The structure of the compound was unequivocally identified by NMR spectroscopy analyses including (1)H-NMR; COSY; ROESY; HSQC and HMBC. The compound was identified as isorhapontigenin (ISOR), a stilbene found in traditional Asian medicinal plants. To the best of our knowledge this is the first report of its occurrence in grapes.

Simulated digestion and antioxidant activity of red wine fractions separated by high speed countercurrent chromatography.

Wine is an important source of dietary antioxidants because of its phenolic compound content. The antioxidant activity (AA) of pure monomer substances present in wines, such as phenolic acids, flavanols, and anthocyanins, has already been described, but the AA of polymeric phenols is still unknown. In this study, we have fractionated a red wine by countercurrent chromatography (CCC) into four fractions: fraction 1, made up of polymeric compounds; fraction 2, containing malvidin-3-glucoside; fraction 3, containing peonidin-3-glucoside; and fraction 4, containing vitisin A. The AA of these fractions was determined by oxygen radical absorbance capacity and ferric reducing ability assays. The weight of fraction 1 was the largest, so this was the largest contributor to the AA of the wine. However, the antioxidant powers (muM Trolox/g fraction) of fractions 2-4 were similar and higher than that of fraction 1. We also determined AA before and after in vitro gastric and intestinal digestions. After gastric digestion, the AA was 100-1000 times higher than the original fraction values. Gallic acid was determined in gastric and intestinal digested fractions. After intestinal digestion, the concentrations of simple phenols, such as caffeic acid, p-coumaric acid, and protocatechualdehyde, increased as they were released from the fractions under our conditions. Protocatechuic acid was determined in more intestinal digested fractions than in gastric digested fractions. These results partly explain the increase in AA after the digestion and indicate the relevance of polymeric polyphenolic compounds as precursors of smaller molecules with biological activity.

El fruto de la acerola: composición, características productivas e importancia económica / The acerola fruit: composition and possible alimentary uses

El objetivo de esta revisión es caracterizar el fruto de la acerola, detallando así sus aspectos taxonómicos, vegetativos, de composición y de mercado. También se evalúa su posible utilización como ingrediente alimentario en vistas a la producción de alimentos funcionales. Para la realización de esta revisión bibliográfica se han consultado bases de datos internacionales (Scifinder Scholar y Medline) y artículos originales que han sido localizados y proveídos principalmente por los Recursos Electrónicos de la Biblioteca de la Universidad de Sevilla y la Universidad do Vale do Itajaí (Santa Catarina, Brazil).La acerola (Malpighia emarginata Sessé y Mociño ex DC) es una especie arbustiva que se desarrolla en zonas de climas tropical y subtropical. Su origen se centra en el sur de México, América Central y zona septentrional de Sudamérica. Su denominación se adoptó en 1986 por el Consejo Internacional de Recursos Genéticos Vegetales. Malpighia emarginata presenta un fruto subglobuloso en forma de drupa, el cual posee tres semillas que representan entre el 19 y el 25 por ciento del peso total. El diámetro del fruto varía de 1 a 4 cm y el peso de 2 a 15 g. Presenta una coloración verde cuando está en desarrollo, cambiando a tonos amarillos y rojos cuando está maduro. La maduración ocurre en corto espacio de tiempo. El período de fructificación es de 3 a 4 veces al año. Cada planta produce cerca de 20 a 30 kg de frutos anualmente. La fruta de acerola proporciona macro y micronutrientes: proteínas (0,21 g/100 g), grasas (0,23 g/100 g), carbohidratos (3,57 g/100 g), sales minerales (hierro (0,24 mg/100 g, calcio 11,7 mg/100 g, fósforo 17,1 mg/100g) y vitaminas (tiamina (0,02 mg/100 g, riboflavina 0,07 mg/100 g, piridoxina 8,7 mg/100 g). Hay que destacar su elevado contenido en vitamina C (695 a 4827 mg/100 g), el cual ha inducido un gran consumo de esta fruta en los últimos años, de ahí su importante valor económico. La acerola también presenta carotenoides y...

Revisión de los métodos de evaluación de la actividad antioxidante in vitro del vino y valoración de sus efectos in vivo / Review of the different methods for the evaluation of the in vitro antioxidant activity of wine and study of in vivo effects

El objetivo de esta revisión es el estudio de la actividad antioxidante del vino, analizando los distintos métodos que se han empleado en su evaluación. Esta actividad se relacionará, tanto desde el punto de vista cualitativo como cuantitativo, con el perfil de compuestos polifenólicos presentes en el vino. Los vinos tintos presentan actividades superiores a los blancos y la magnitud de dichos valores varía en función del método de análisis empleado. No existe un único compuesto polifenólico responsable mayoritariamente de la actividad antioxidante del vino, sino que ésta se explica por el conjunto de todos ellos. Para evaluar la influencia del consumo de vino tinto en el organismo humano se ha utilizado como biomarcador más frecuente la capacidad antioxidante del plasma, que incrementa su valor tras la ingesta del vino. Se expone que la evaluación de la actividad antioxidante in vitro del vino requiere el uso de diversos métodos que proporcionen una información diferente y complementaria. Los métodos in vivo tienen la ventaja de valorar las transformaciones metabólicas que sufren los fenoles en el organismo y que modifican su actividad. De los estudios realizados hasta la fecha se concluye que el vino interviene en la capacidad antioxidante del plasma de forma directa a través de sus compuestos polifenólicos e indirecta al aumentar la concentración plasmática de ácido úrico