68 research outputs found

    Synergism Effect between Phenolic Metabolites and Endogenous Antioxidants in Terms of Antioxidant Activity

    Get PDF
    Polyphenolic compounds, widely distributed in plant kingdom, have been exhaustively studied for their bioactive properties specially antioxidant activity. However, they are extensively metabolized by human organism and the resulting metabolites are largely responsible for their effects. Furthermore, they may interact with the endogenous antioxidant network being this possibility scarcely studied. Plasma antioxidant network encompasses antioxidant enzymes and other substances such as uric acid. In addition, ascorbic acid is the major compound representing water soluble compartment both in foods and human body. The interaction of this vitamin with phenolic compound is largely unexplored. This work aims to study if there is a synergic effect between phenolic metabolites and main antioxidants (uric and ascorbic acid). For this purpose, the antioxidant activity was evaluated in terms of ORAC (oxygen radical absorbance capac ity) and FRAP (ferricreducing antioxidant power) as these tests involved either HAT (Hydrogen Atom Transfer) or SET (Single Electron Transfer) mechanisms. Additionally, a kinetic studied was developed to test if the rate constant presented a synergic effect. Protocatechuic acid, 3, 4 -dihydroxyphenylacetic acid, 3,4 -dihydroxyphenylpropionic acid and 3 -hydroxyphenylacetic acid were selected as they were metabolites of polyphenol compounds such as anthocyanins, quercetin, neohesperidin, chlorogenic acid and hesperetin present in wines, orange and strawberries. A synergic effect was proved for the combination of ascorbic acid with 3,4 -dihydroxyphenylacetic acid, both in terms of antioxidant activity and potent increase of velocity of the antioxidant reaction that took place.Ministerio de Economía y Competitividad AGL-2010-22152-C03-0

    Acetic Acid Bacteria and the Production and Quality of Wine Vinegar

    Get PDF
    The production of vinegar depends on an oxidation process that is mainly performed by acetic acid bacteria. Despite the different methods of vinegar production (more or less designated as either “fast” or “traditional”), the use of pure starter cultures remains far from being a reality. Uncontrolled mixed cultures are normally used, but this review proposes the use of controlled mixed cultures. The acetic acid bacteria species determine the quality of vinegar, although the final quality is a combined result of technological process, wood contact, and aging. This discussion centers on wine vinegar and evaluates the effects of these different processes on its chemical and sensory properties

    Key odorants of the typical aroma of Sherry vinegar

    Get PDF
    A representative Sherry vinegar was analysed by gas chromatography-olfactometry (GC-O). Two GC-O techniques were used targeting compounds with impact on the perceived quality of Sherry vinegar, i.e. detection frequency and aroma extract dilution analysis. A total of 108 aromatic notes were detected and 64 of them were identified. Diacetyl, isoamyl acetate, acetic acid, and sotolon reached the highest frequency and flavour dilution (FD) factors. Ethyl acetate accounted for the maximum frequency but had only a FD factor of 4. Similarity tests were performed between the Sherry vinegar and model solutions of all possible combinations of these compounds. The highest value from the similarity test was observed when diacetyl, ethyl acetate and sotolon were added simultaneously. The profile of this model solution and the representative Sherry vinegar showed a good similarity in the general aroma description, which emphasises the important contribution of these 3 compounds to the global aroma of this vinegar

    Chemical and pharmacological properties of the fruit guaraná (Paullinia cupana)

    Get PDF
    Esta revisión tiene por objeto presentar una descripción general del Guaraná, abarcando tanto sus propiedades químicas y farmacológicas como su aspecto económico, producción y consumo. Se han seleccionado un total de 82 artículos de los que se recogen las características botánicas y químicas, la actividad farmacológica y las propiedades medicinales del Guaraná, en el período comprendido entre 1931 y 2005.This review involves a general description of Guaraná, including its chemical and pharmacological properties as well as its production, consumption and economical importance. The revision covers the period between 1931 and 2005, in which 82 papers are considered concerning the botanic and chemical characteristics, the pharmacological activity and the medicinal properties of Guaraná

    Antioxidant capacity (ORAC FL) of frozen fruits’ pulps

    Get PDF
    The production of fruits’ pulps has reached growing regional and international market. This is basically due to the fact that they are easily available to the consumers together with the benefits of a rich diet with substantial antioxidant activity. Even more, the properties of phenolic compounds and powerful antioxidant potential of fruits are associated to the human health. This work aimed to determine the antioxidant activity of the pulps from commercial fruits (mulberry, grape, açaí, guava, strawberry, acerola, pineapple, mango, graviola, cupuaçu and passion fruit) applying the method: ORACFL. The total polyphenol content (PT), the total flavanol content (TF) and the total anthocyanin (TA) were evaluated with the object of assessing the contribution for the antioxidant capacity. The acerola and mango pulps contained a high amount of total polyphenols (580.1 and 544.9mg/100g respectively) while mulberry and grape were the pulps which presented the highest amount of anthocyanins (41.8 and 30.9 mg/100g); strawberry and acerola were the pulps that presented higher amount of flavanol (83.4 and 75.8mg/100g). In addition, higher values of flavanoles corresponded to the strawberry and acerola pulps. The antioxidant activity determined by ORAC FL in pulps of frozen fruits is presented in the following order: acerola> strawberry> mango> grape> açaí >graviola> guava> cupuaçu> passion fruit> pineapple> mulberry.La producción de pulpa de frutas en Brasil está ganando mercado tanto a nivel regional como internacional. Esto se debe a la facilidad que representa para los consumidores la adquisición del producto, unido a los beneficios de una dieta rica en compuestos antioxidantes. Las evidencias cuanto a la capacidad antioxidante de las frutas estar determinada por la presencia de los fenoles son cada vez más aceptadas, así como también, los beneficios que representan para la salud. El objetivo del trabajo fue determinar la capacidad antioxidante de pulpa de frutas comerciales congeladas. Fueron analizadas pulpas de mora, uva, asaí, guayaba, frutilla, acerola, piña, mango, graviola, cupuassu y maracuyá. La actividad antioxidante fue determinada por un método in vitro ampliamente utilizado: ORACFL (capacidad de absorbancia del radical oxígeno), la concentración de poli fenoles totales (PT), flavonoles totales (FT) y de pigmentos antocianinas (AT). Los resultados obtenidos muestran que las pulpas de acerola y mango presentan mayor concentración de fenoles totales (580,1 y 544,9mg/100g respectivamente) mientras que las pulpas de mora y uva una mayor cantidad de antocianinas (41,8 y 30,9mg/100g respectivamente) y las pulpas de frutilla y acerola mayores valores para flavonoles (83,4 y 75,8mg/100g respectivamente). En relación a la capacidad antioxidante, en orden decreciente de actividad están: acerola > frutilla > mango > uva> asaí > graviola > guayaba > cupuassu >maracuyá > piña > mora.A produção de polpas de frutas no Brasil ganha mercado tanto em nível regional, como internacional. Este fato se deve à facilidade de aquisição pelos consumidores somados aos efeitos benéficos de uma dieta rica em compostos antioxidantes. Cada vez mais, se atribui, aos compostos fenólicos o potencial antioxidante das frutas e suas possíveis implicações benéficas à saúde humana. O objetivo deste trabalho foi determinar a capacidade antioxidante de polpas de frutos comerciais congeladas. Em polpas de amora, uva, açaí, goiaba, morango, acerola, abacaxi, manga, graviola, cupuaçu e maracujá determinou-se a atividade antioxidante aplicando um método in vitro ampliamente utilizado: ORAC FL (capacidade de absorbância do radical oxigênio), a concentração de polifenóis totais (PT), flavanóis totais (FT) e de pigmentos antociânicos (AT). Os resultados encontrados demonstram que as polpas de acerola e manga apresentaram maior concentração de fenólicos totais (580,1 e 544,9mg/100g, respectivamente), enquanto que, as polpas de amora e uva uma maior quantidade de antocianinas (41,8 e 30,9mg/100g), e as polpas de morango e acerola maiores valores de flavanóis (83,4 e 75,8mg/100g). Com respeito à capacidade antioxidante, em ordem decrescente as polpas que demonstraram maior atividade foram: acerola> morango> manga> uva> açaí>graviola> goiaba> cupuaçu> maracujá>abacaxi> amora

    Inhibition of VEGF-Induced VEGFR-2 Activation and HUVEC Migration by Melatonin and Other Bioactive Indolic Compounds

    Get PDF
    Excessive concentrations of vascular endothelial growth factor (VEGF) trigger angiogenesis, which causes complications such as the destabilization of atherosclerotic plaques and increased growth of tumors. This work focuses on the determination of the inhibitory activity of melatonin and other indolic related compounds on VEGF-induced VEGF receptor-2 (VEGFR-2) activation and an approximation to the molecular mechanism underlying the inhibition. Quantification of phosphorylated VEGFR-2 was measured by ELISA. Migration wound-healing assay was used to determine cell migration of human umbilical vein endothelial cells (HUVECs). This is the first time that melatonin, 3-indolacetic acid, 5-hydroxytryptophol, and serotonin are proved to significantly inhibit VEGF-induced VEGFR-2 activation in human umbilical vein endothelial cells and subsequent angiogenesis. 3-Indolacetic acid showed the highest inhibitory effect (IC50 value of 0.9704 mM), followed by 5-hydroxytryptophol (35% of inhibition at 0.1 mM), melatonin (30% of inhibition at 1 mM), and serotonin (24% of inhibition at 1 mM). An approximation to the molecular mechanism of the inhibition has been proposed, suggesting that indolic compounds might interact with the cell surface components of the endothelial membrane in a way that prevents VEGF from activating the receptor. Additionally, wound-healing assay revealed that exposure of HUVECs to melatonin and 3-indolacetic acid in the presence of VEGF significantly inhibited cell migration by 87% and 99%, respectively, after 24 h. These data demonstrate that melatonin, 3-indolacetic acid, 5-hydroxytryptophol, and serotonin would be good molecules for future exploitation as anti-VEGF signaling agents.España, Ministerio de Ciencia e Innovación AGL2013-47300-C3-2-

    Time course of l-tryptophan metabolites when fermenting natural grape musts: effect of inoculation treatments and cultivar on the occurrence of melatonin and related indolic compounds

    Get PDF
    Background and Aims:Tryptophan is involved in the formation of bioactive compounds, such as melatonin (MEL) and3-indoleacetic acid (3-IAA), by yeast. Melatonin is a neurohormone whose occurrence in wine has been widely reported inrecent years. The occurrence, however, of MEL and other indolic compounds related to tryptophan metabolism by wineyeast strains has been scarcely reported in grape musts. This work examined the occurrence of these compounds during thealcoholic fermentation (AF) of musts from seven grape cultivars, Corredera, Chardonnay, Moscatel, Palomino Fino, Sau-vignon Blanc, Tempranillo and Vijiriega.Methods and Results:Must was fermented with threeSaccharomyces cerevisiaestrains and then in two cases an additionalsequential inoculation with the non-SaccharomycesyeastTorulaspora delbrueckiiwas carried out. Fermented must samples wereanalysed by UHPLC/HRMS to determine the concentration of:L-tryptophan, 5-hydroxytryptophan, 5-hydroxytryptamine,N-acetyl-5-hydroxytryptamine, MEL, 3-IAA, tryptamine, tryptophol andL-tryptophan ethyl ester. The profile of indoliccompounds during AF with the Aroma White strain depended on the cultivar. The yeast strain did not influence the profile ofindolic compounds; instead, fermentation time was found to be a more influential factor.Conclusions:The production of indolic compounds during the AF depends largely on the cultivar used and the day of fer-mentation on natural grape musts.Significance of the Study:This is thefirst study that quantifies 5-hydroxytryptophan andN-acetyl-5-hydroxytryptamineduring the AF of grape must. The occurrence of compounds with bioactive potential, for example 3-IAA and ML, during fer-mentation with commercial yeast strains is also described.Ministerio de Economía y Competitividad de España - AGL2013-47300-C3-2-R, 2014–16 y AGL2016-77505-C3-2-R, 2017–1

    Palm Oil on the Edge

    Get PDF
    Internationally recognized Spanish experts in the food industry, nutrition, toxicology, sustainability, and veterinary science met in Madrid on July 2018 to develop a consensus about palm oil (PO) as a food ingredient. Their aim was to provide a useful, evidence-based point of reference about PO. Scientific evidence about the role of PO in food safety, nutrition and sustainability was analyzed. Main conclusions were: (1) RSPO foundation responded to the environmental impact of palm crops. The Amsterdam Declaration pursues the use of 100% sustainable PO in Europe by 2020. Awareness about choosing sustainable products will help to maintain local economies and environments in the producing countries; (2) evidence shows that a moderate intake of PO within a healthy diet presents no risks for health. No evidence justifies any change fat intake recommendations; (3) food industry is interested in assuring safe, sustainable and high-quality products. The use of certified sustainable PO is increasing; and (4) there is no evidence associating PO consumption and higher cancer risk, incidence or mortality in humans. Tolerable daily intake (TDI) for toxic contaminants (2-and 3-monochloropropanediols (MCPDs), glycidyl esters (GEs)) have been established by JECFA and EFSA. Consequently, the European Commission has modified the Contaminants Regulation for GEs and it is still working on 3-MCPDs’

    Bioactive compounds derived from the yeast metabolism of aromatic amino acids during alcoholic fermentation

    Get PDF
    Metabolites resulting from nitrogen metabolism in yeast are currently found in some fermented beverages such as wine and beer. Their study has recently attracted the attention of researchers. Some metabolites derived from aromatic amino acids are bioactive compounds that can behave as hormones or even mimic their role in humans and may also act as regulators in yeast. Although the metabolic pathways for their formation are well known, the physiological significance is still far from being understood. The understanding of this relevance will be a key element in managing the production of these compounds under controlled conditions, to offer fermented food with specific enrichment in these compounds or even to use the yeast as nutritional complement

    Results for Greenland halibut, American plaice and Atlantic cod of the Spanish survey in NAFO Div. 3NO for the period 1997-2010.

    Get PDF
    Greenland halibut (Reinhardtius hippoglossoides), American plaice (Hippoglossoides platessoides) and Atlantic cod (Gadus morhua) indices from the bottom trawl survey that Spain carries out in Spring since 1995 in Div. 3NO of the NAFO Regulatory Area are presented. Mean catch per town, biomass, length and age distributions for the three species are presented since 1997, year in which the survey extended the depth strata. In 2001, the R/V Vizconde de Eza replaced the C/V Playa de Menduíña in the execution of the survey. We present the transformed to the R/V Vizconde de Eza series for the period 1997-2000, and the original obtained data for the period 2002-2009. In 2001, there are data from the two vessels. Greenland halibut biomass and abundance estimates present a decreasing trend since 1999, cut in year 2007 with a slight increase and a high increase since 2008, reaching in 2009 the highest value in the series. In last years it can be seen a presence of juveniles, mainly in 2004, but the greatest lengths have failed, altough in 2009 there is a quite good presence of individuals of ages 6-7 and in 2010 between 5-7. For American plaice we can see an increasing trend along the whole period, reaching a maximum of biomass and number in 2006, following by the 2008 indices, cut in 2009 with a decrease in the indices, remains in a lower value than in the year 2003 following with a sligth increase in 2010. The greatest recruitment in the presented series occurred in 2004 and we can follow their mode along the years, reaching its maximum in 2008. For Atlantic cod we can see a general decreasing in the biomass between 2002 and 2005, and an increasing since then, especially in 2006 and, higher, in 2009 and 2010, although this values is mainly due to a few hauls with high catches. In 2007 the biomass decreased, but the level is over the value in the period 2002-2005. For this species, an increase in the recruitment can be seen in 2004 and 2005, and from 2007 the youngest length classes are much over the rest of the length classes. With the 2006 cohort the series reaches the masimum number of its historical values at four years in 2010
    corecore