Enzymes modulation by dried grape pomace from the manufacture of wines and juices

The processing of grapes for the manufacture of juices and wines, generates large quantities of by-products rich in metabolites with antioxidant, antimicrobial, anti-inflammatory and cicatrizing activities. The high homology between human enzymes and snake venoms makes the latter valuable laboratory tools for the study of pathophysiological processes. Proteases and phospholipases A2 act in processes related to hemostasis and inflammatory response. Thus, in this work, dried pomace obtained from grape (Isabel, Niagara, Bordô, BRS Violeta and Blend cultivars) processing were evaluated on phospholipase, proteolytic, hemolytic and thrombolytic activities induced by snakes venoms and the content of phenolic compounds and minerals was evaluated. The dried pomace exerted inhibitory and potentiating actions in all analyzed activities. The enzymatic modulators present in the evaluated dried pomace have potential for therapeutic use, although their broad characterization is still necessary, in order to define adequate amounts and formulations to obtain efficacy and safety in their use.

Polymeric micelles containing resveratrol: development, characterization, cytotoxicity on tumor cells and antimicrobial activity

Antimicrobial and antitumor activities of resveratrol, a compound found mainly in grapes, have already been demonstrated. However, its low bioavailability is a limiting factor for therapeutic application. Polymeric micelles can be an approach to solve this problem since they can encapsulate hydrophobic substances. We developed and characterized micellar formulations containing resveratrol and evaluated their cytotoxic and antimicrobial effects. The formulations were prepared by the cold dispersion method with different concentrations of F127 (5 or 10% w/w) and resveratrol (500 or 5000 µM). The formulations were characterized according to size, polydispersity index, pH, encapsulation rate and in vitro release. Cytotoxic effect was evaluated on a bladder cancer cell line and antimicrobial effect was evaluated on E. coli, S. aureus and C. albicans. One of the formulations (10% w/w of F127 and 5000 µM of resveratrol) was a monodispersed solution with high encapsulation rate, thus it was chosen for the cytotoxicity and antimicrobial assays. MS- 10+RES-3 was able to preserve the antimicrobial and cytotoxic activity of resveratrol. This is the first study that evaluated antimicrobial potential and cytotoxicity of micelles containing resveratrol on bladder cancer cells and the results showed that micellar nanostructures could ensure the maintenance of the biological activity of resveratrol.

Sugars, organic acids, and phenolic compounds of ancient grape cultivars (Vitis vinifera L.) from Igdir province of Eastern Turkey

BACKGROUND: The Eurasian grapevine (Vitis vinifera L.) is the most widely cultivated and economically important horticultural crop in the world. As a one of the origin area, Anatolia played an important role in the diversification and spread of the cultivated form V. vinifera ssp. vinifera cultivars and also the wild form V. vinifera ssp. sylvestris ecotypes. Although several biodiversity studies have been conducted with local cultivars in different regions of Anatolia, no information has been reported so far on the biochemical (organic acids, sugars, phenolic acids, vitamin C) and antioxidant diversity of local historical table V. vinifera cultivars grown in Igdir province. In this work, we studied these traits in nine local table grape cultivars viz. 'Beyaz Kismis' (synonym name of Sultanina or Thompson seedless), 'Askeri', 'El Hakki', 'Kirmizi Kismis', 'Inek Emcegi', 'Hacabas', 'Kerim Gandi', 'Yazen Dayi', and 'Miskali' spread in the Igdir province of Eastern part of Turkey. RESULTS: Variability of all studied parameters is strongly influenced by cultivars (P < 0.01). Among the cultivars investigated, 'Miskali' showed the highest citric acid content (0.959 g/l) while 'Kirmizi Kismis' produced predominant contents in tartaric acid (12.71 g/l). The highest glucose (16.47 g/100 g) and fructose (15.55 g/100 g) contents were provided with 'Beyaz Kismis'. 'Kirmizi Kismis' cultivar had also the highest quercetin (0.55 mg/l), o-coumaric acid (1.90 mg/l), and caffeic acid (2.73 mg/l) content. The highest ferulic acid (0.94 mg/l), and syringic acid (2.00 mg/l) contents were observed with 'Beyaz Kismis' cultivar. The highest antioxidant capacity was obtained as 9.09 μmol TE g-1 from 'Inek Emcegi' in TEAC (Trolox equivalent Antioxidant Capacity) assay. 'Hacabas' cultivar had the highest vitamin C content of 35.74 mg/100 g. CONCLUSIONS: Present results illustrated that the historical table grape cultivars grown in Igdir province of Eastern part of Turkey contained diverse and valuable sugars, organic acids, phenolic acids, Vitamin C values and demonstrated important antioxidant capacity for human health benefits. Further preservation and use of this gene pool will be helpful to avoid genetic erosion and to promote continued agriculture in the region.

The main potentialities of resveratrol for drug delivery systems

Resveratrol (RSV), a natural polyphenol found in grapes, was found to be effective in the prevention and therapy of several diseases, however, it does have unfavourable physicochemical properties. In this context, an increasing number of studies have aimed at developing novel therapeutic systems for its delivery to overcome these disadvantages. This review focuses on the mechanisms of action and therapeutic applications. Finally, it also describes some tested formulations for RSV administration, controlled release and targeting, developed with the purpose of increasing RSV bioavailability.

O resveratrol (RSV) é um polifenol natural encontrado nas uvas, que se mostrou eficaz na prevenção e terapia de várias doenças. No entanto, apresenta propriedades físico-químicas desfavoráveis. Neste contexto, um número cada vez maior de estudos visando ao desenvolvimento de novos sistemas terapêuticos para a sua liberação vem sendo desenvolvido no sentido de ultrapassar estas desvantagens. Esta revisão discorre sobre os mecanismos de ação e aplicações terapêuticas do RSV. Finalmente, são abordadas algumas formulações de liberação controlada e vetorizada, testadas para administração do RSV, desenvolvidas com a finalidade de aumentar a biodisponibilidade do RSV.

Isolation and characterization of lactic acid bacteria and yeasts from the Brazilian grape sourdough

Sourdough is a mixture of flour and water fermented by lactic acid bacteria and yeast, with a large use in bakery products. This study was developed with Brazilian grape (Niagara rosada) sourdough obtained from spontaneous fermentation. The aim of this work was to characterize genotypic and phenotypically lactic acid bacteria and yeasts isolated from sourdough. The phenotypic identification for bacteria and yeasts was performed by using the kit API50CHL and 20CAUX and the genotypic characterization was performed by sequencing method. A total of four isolated strains were analyzed in this study. Two of these strains were phenotypically and genotypic identified as Lactobacillus paracasei and one as Saccharomyces cerevisiae. Another sample phenotypically identified as Candida pelliculosa did not show the same identity by sequencing. It shows the need to use phenotypic and genotypic characterization associated for the correct microorganism identification.

Fermento natural é mistura de farinha e água fermentada por bactérias láticas e leveduras, amplamente utilizada em produtos de panificação. Neste estudo desenvolveu-se um fermento natural de uva brasileira (Niagara rosada), obtido a partir de fermentação espontânea. O objetivo deste trabalho foi caracterizar fenotipicamente e genotipicamente bactérias láticas e leveduras isoladas do fermento natural de uva. A identificação fenotípica para bactéria lática e leveduras foi realizada usando os kits API50CHL e 20CAUX e a caracterização genotípica foi realizada pelo método de sequenciamento. Neste estudo, isolaram-se quatro cepas. Duas cepas foram identificadas fenotipicamente e genotipicamente como Lactobacillus paracasei e outra cepa como Saccharomyces cerevisiae. A outra amostra de levedura, identificada fenotipicamente como Candida pelliculosa, não obteve a mesma identidade com a técnica de sequenciamento. Isso mostra a necessidade do uso da caracterização fenotípica e genotípica em associação para a correta identificação do micro-organismo.

Fate of ochratoxin A content in Argentinean red wine during a pilot scale vinification / Evolución del contenido de ocratoxina A en vinos tintos argentinos durante el proceso de vinificación a escala piloto

The aim of this work was to evaluate the fate of ochratoxin A (OTA) content from must to wine during the red wine making process in a pilot scale vinification. The study was done using musts obtained from two red grape varieties (Bonarda and Tempranillo) artificially contaminated with two OTA levels. A duplicate set of tanks of 100 l each was established for each must (Bonarda and Tempranillo). The fermentations were initiated by inoculation of two Saccharomyces spp. strains having different fermentation performance. The must from the Tempranillo variety was spiked with 6 μg/l of OTA while that from the Bonarda variety with 0.3 μg/l of the toxin. Samples were collected at different stages of the process. Performance of the alcoholic and malolactic fermentations was monitored. Titratable and volatile acidity, pH, ethanol, sugar and SO2 concentrations were determined following standard methods proposed by the Office International de la Vigne et du Vin (OIV). OTA analysis was done by HPLC. Detection and quantification limits were 0.01 and 0.1 ng/ml, respectively. The OTA levels during the vinification trials dropped to an average of about 86.5%. The type of Saccharomyces strains used showed no effect on toxin reduction.

El objetivo del presente trabajo fue evaluar la evolución del contenido de ocratoxina A (OTA) en mostos durante un proceso de vinificación a escala piloto. Se utilizaron mostos de dos variedades de uvas tintas (Bonarda y Tempranillo) contaminados artificialmente con dos niveles distintos de OTA. El ensayo fue llevado a cabo por duplicado en tanques de fermentación de 100 l cada uno. La fermentación se inició mediante la inoculación de dos cepas de Saccharomyces spp. con diferentes características fermentativas. El mosto de la variedad Tempranillo fue contaminado con 6 μg/l de OTA y el mosto de la variedad Bonarda con 0,3 μg/l de la toxina. Se colectaron muestras durante los diferentes estadios del proceso de vinificación. Se estableció el avance de dicho proceso sobre la base de la evolución de las fermentaciones alcohólica y maloláctica. Se determinó la acidez total y volátil, el pH y el contenido de etanol, de azúcar y de SO2 siguiendo los protocolos estándares propuestos por la Oficina Internacional de la Vid y el Vino (OIV). El contenido de OTA se evaluó por HPLC. Los límites de detección y cuantificación fueron 0,01 y 0,1 ng/ml, respectivamente. Los niveles de OTA disminuyeron alrededor del 86,5% al final del proceso de vinificación. El tipo de cepa de Saccharomyces spp. utilizada no tuvo efecto sobre la reducción de OTA.

Microinjerto in vitro de vid (Vitis vinifera) / In vitro micrograft of vine (Vitis viniferous)

Se implementó la técnica de microinjerto in vitro de meristemos apicales de dos variedades productoras de vid, además trata de la importancia del cultivo de la vid en Bolivia tomando en cuenta la calidad de los viñedos.