Wine Extracts Research Articles

The effect of wine age and tannin composition on tannin activity across consecutive Pinotage red wine vintages

The effect of wine age on tannin chemistry and tannin activity values was investigated in red wine extracts according to a chemosensory approach. Sixteen Pinotage red wines of multiple vintages (2003-2018) were each isolated into four distinct polymeric fractions (F1-F4) on Sephadex LH-20 by flash-column chromatography. Tannin activity increased with molecular weight, where F1 was associated with positive values, reported for the first time, suggesting a different interaction mechanism than the usual exothermic value obtained in more polymerised samples such as F2 and F3. Weakly positive correlations were observed between tannin activity and tannin concentration by RPLC. Moderately positive correlations were obtained between either tannin estimation techniques, yet this was highly dependent on wine age and molecular size. Overall, tannin activity decreased across all vintages as a function of wine age, indicative of age-related reactions such as tannin oxidation, cleavage and precipitation. Chemosensory studies showed that while activity values across all fractions explained little variation, lowly positive correlations existed between larger polymeric fractions (F3 and F4) and mouthfeel attributes, namely astringency and bitterness, suggesting that highly polymerised tannins with higher activity values play a significant role in mouthfeel modification. More research is required to understand the actual sensory perception of proanthocyanidin size in red wine proanthocyanidin extracts and tannin-derived pigments (as opposed to wine) and to what extent it is influenced by parameters such as tannin activity across long-term ageing.

Development of gelatin/PVA based colorimetric films with a wide pH sensing range winery solid by-product (Vinasse) for monitor shrimp freshness

Anthocyanins were extracted from a winery solid by-product (Vinasse) and added to fish gelatin (FG) and polyvinyl alcohol (PVA) matrices to create freshness monitoring labels. Three different colorimetric indicator smart films [PWE = polyvinyl alcohol with wine extract (WE), FWE = fish gelatin with WE, and PFWE = polyvinyl alcohol and FG blended film with WE] were generated and examined for their suitability to monitor the freshness of shrimp. The mechanical and optical properties, ammonia sensitivity, and colorimetric analysis of smart films were determined. Fourier transform-infrared spectroscopy (FTIR) was used to evaluate the interaction of anthocyanins with FG and PVA and changes in the film's chemical composition with storage. The film surfaces were characterized with atomic force microscopy (AFM). The incorporation of WE enhanced the films' flexibility by providing plasticizer and surfactant properties. The PWE film showed the best color stability. The FWE film showed the least amount of total color change with exposure to ammonia gas and was deemed suitable for refrigerated food packaging. The color of all indicator films showed significant changes suggesting that PWE, FWE, and PFWE films can be utilized in the intelligent packaging application for protein-rich foods to detect spoilage.

Flavor and Rapid Prediction of Red Wine by the Chemometrics Algorithm Based on Multidimensional Spectral Data.

Since its birth, red wine has been loved by people of all walks of life. The taste of red wine has changed and the pursuit of quality has always been the most sought-after goal by sommeliers, winemakers, and the public. However, due to the rich taste of red wine, any link is willing to produce different flavors. At present, there is no quantitative control study on the flavor of red wine. The purpose of this paper is to analyze the flavor of red wine through the chemometric algorithm and establish a reasonable model to predict the flavor of red wine. Aiming at the research of red wine flavor, this paper designs a red wine flavor extraction experiment and extracts the substances that produce an aroma and flavor in red wine to the greatest extent through strict selection of extraction head and reaction time. For the rapid analysis of red wine flavor, this paper quantitatively describes the chemical category, volatilization time, molecular weight, etc., of flavor substances by analyzing the multidimensional spectral data of red wine, so that flavor substances can be quickly located. The experimental results of this paper prove that, for different red wines, the algorithm in this paper can accurately identify the flavor substances in red wine. Also, for red wine multidimensional spectral data, the algorithm in this paper can improve the accuracy by 30% and save the running time by 30%. This shows that the research in this paper can analyze and quickly predict the flavor of red wine.

Bisexual lures and their comparison with synthetic sex attractants for trapping Orthosia species (Lepidoptera: Noctuidae)

AbstractTwo bisexual lures have been developed using iso‐amyl alcohol plus acetic acid combined with red wine extract (semisynthetic bisexual lure, SBL), or synthetic floral compounds (FLO) for trapping of noctuid moths with early spring activity of adults. Orthosia species were attracted by the tested semi‐synthetic and synthetic lures indicating the possible role of the fermenting liquids and floral compounds in the feeding of these species. Bisexual lures attracted generally a lower number of individuals than the synthetic sex attractants of the given species, except for O. cerasi where FLO lures were more attractive than the sex attractant. Bisexual lures caught both sexes and females composed a sizable percentage of the catch. Since traps baited with different types of bisexual lures provided similar data on sex ratios, thus these presumably reflected the actual sex ratio of the given population. The use of these bisexual lures, especially of FLO in case of Orthosia spp., can be useful in surveys in which the capture of females and data on sex ratios are indispensable, for example in population dynamic and polyandry surveys. In contrast, in case of low population densities, the use of sex attractant lures seem to be still more efficient.

Fluorescent enzymatic assay for direct total polyphenol determination in food-related samples

A direct and simple fluorescent assay for the total polyphenol determination based on the bioconjugate formed between the laccase enzyme (TvL from Trametes versicolor) and carbon nanodots (CD) is developed. One of the most used reactions for the determination of phenols is based on the enzymatic reaction of their oxidation to quinones. In this work, CD has been biofunctionalized with TvL (TvL-CD) and employed as a fluorescent label to follow the enzymatic reaction. The bioconjugate was formed and characterized by spectroscopy and microscopy. The optimal TvL-CD ratio was established. The reaction between the bioconjugate and a phenolic compound such as gallic acid (GA) was followed by monitoring the fluorescence bioconjugate decrease due to the quenching effect of the quinones generated in the enzymatic reaction. These studies confirm that bioconjugation does not inhibit the enzymatic activity and the fluorescence decrease during the enzymatic reaction is mainly due to an electron transfer processes. Based on these results, a new method for the quantitative determination of polyphenols measured as GA concentration is developed. The detection and quantification limit was found to be 7.4 and 25 μM, respectively. Subsequently, the method has been applied to the direct determination of GA in wine, juice, and rice leaf extracts.

Activation of platelet-adherent basophils in chronic rhinosinusitis with alcohol hypersensitivity

BackgroundAlcohol hypersensitivity (AH), an exacerbation of respiratory symptoms in response to alcohol consumption, is common in aspirin-exacerbated respiratory disease and other forms of chronic rhinosinusitis (CRS). We speculated that these reactions relate to the activation of innate immune cells including basophils and, in particular, platelet-adherent basophils by polyphenolic compounds contained within eliciting alcoholic beverages. ObjectiveWe investigated the absolute numbers of these cells in patients with AH and the ability of relevant polyphenolic compounds to cause cellular activation. MethodsData were collected from 412 consecutive adults presenting to a tertiary care sinonasal clinic in whom the presence of AH was elicited. The CRS phenotype was determined and results from complete blood cell count and differential were analyzed. A subset of patients was invited to donate blood samples that were used to explore the ability of relevant compounds associated with alcohol consumption to activate platelet-nonadherent and platelet-adherent basophils. Activation was quantified by flow cytometry as up-regulated expression of CD63 and as secretion of lipid metabolites. ResultsOf the 412 patients enrolled, 69 (16.7%) endorsed having AH. Significantly higher platelet counts were seen in patients reporting AH. Red wine extract and several polyphenolic compounds produced basophil activation and this was primarily observed among platelet-adherent basophils. Platelet activation was further established as the release of thromboxane B2. ConclusionThe presence of AH is associated with significantly higher platelet levels and compounds present in alcoholic beverages can directly mediate both their activation and the activation of platelet-adherent basophils.

"Good Wine Makes Good Blood": An Integrated Approach to Characterize Autochthonous Apulian Grapevines as Promising Candidates for Healthy Wines.

Wine production represents an ancient human activity and one of the most economically important markets in Europe. Moreover, the health effects of grapes and related products have been largely demonstrated, and mostly depend on their richness in bioactive molecules such as flavonoid and non-flavonoid phenolic compounds. Italy has the highest global wine production and provides one of the richest grapevine germplasm in the Mediterranean area. In this paper, our attention was focused on the evaluation of the total phenol and anthocyanin content in five autochthonous Apulian grapevine cultivars, in both wines and their non-alcoholic extracts. Moreover, the potential antioxidant effects of the non-alcoholic wine extracts on the cell viability of Caco-2 and HeLa carcinoma cell lines were tested. Finally, for the most promising autochthonous selected cultivars (Negramaro, Nero di Troia and Susumaniello), comparative transcriptomic analysis in berries was performed using high-throughput sequencing technology.

Specificity of Saliva Esterases by Wine Carboxylic Esters and Inhibition by Wine Phenolic Compounds Under Simulated Oral Conditions.

The specificity of human esterase activity (EA) from the stimulated (SS) and non-stimulated (NSS) saliva toward different typical wine odorant carboxylic esters and its inhibition by the wine phenolic compounds has been evaluated. For the specificity, six p-nitrophenyl linked esters with different carbon chain lengths (from 2 to 12 carbons) were employed. The five single phenolic compounds (catechin, quercetin, kaempferol, myricetin, and resveratrol) at typical wine concentrations were assayed in the salivary EA inhibition study. Additionally, the inhibition exerted by the mixtures of wine polyphenols was evaluated using four commercial phenolic extracts [a grape seed extract (GSE), the monomers and oligomer fraction of the GSE, and a red wine extract (RWE)]. Finally, the saliva EA under the wine consumption conditions (pH = 5 and 11.3% ethanol) was evaluated. The results showed a higher EA in SS than NSS. It was also shown that the EA was higher toward the smaller than bigger esters regardless of the saliva types (SS or NSS). However, the inhibition exerted on saliva EA by the individual and mixtures of phenolic compounds was proven. Catechin was the phenolic compound that mostly inhibited saliva EA, while resveratrol showed the lowest EA inhibition. This inhibition was mainly related to the concentration of the phenolic compounds, but also with its structure. Finally, under simulated wine consumption, a decrease in EA was produced, which was mainly provoked by the decrease in the salivary pH. Nonetheless, since salivary pH recovers a few seconds after wine consumption, saliva EA might be relevant for the long-lasting perception of wine esters.

Phenolic Analysis and In Vitro Biological Activity of Red Wine, Pomace and Grape Seeds Oil Derived from Vitis vinifera L. cv. Montepulciano d'Abruzzo.

Grape pomace is commonly considered a waste product of monovarietal red wine production. Methods: HPLC-DAD analysis was performed to determine the polyphenol and flavonoid contents of all the extracts obtained from Montepulciano d’Abruzzo red wine and grape skins whereas, GC-MS was applied to the determination of fatty acid composition in grape seeds oil. Biological characterization involves antioxidant and antimicrobial assays for all the extracts and seeds oil; Their ability to inhibit α-glucosidase, α-amylase, α-tyrosinase, and ChE enzymes was also detected, together with anti-inflammatory activity on wine, grape skin extracts, and seeds oil by lipoxygenase (5-LOX) and LPS-stimulated macrophage release assays. Data indicate significative polyphenols content (199.31 ± 7.21 mgGAE/g), antioxidant (CUPRAC assay (1036.98 mgTE/g)), enzymatic inhibition (α-tyrosinase: 151.30 ± 1.20 mgKAE/g) and anti-inflammatory activities for wine-organic extract 2, while the antimicrobial activity of grape skin decoction is higher than those reported by wine extracts on three bacterial strains. Interestingly only dealcoholized wine and wine-aqueous extract exerts inhibitory effects on α-glucosidase (20.62 ± 0.23 mmolACAE/g and 19.81 ± 0.03 mmolACAE/g, respectively), while seeds oil is rich in oleic and linoleic acids. These results confirm the strong antioxidant properties of Montepulciano d’Abruzzo grape pomace, suggesting the potential use of this waste product as functional food supplements in the human diet and in cosmeceutics.

Comprehensive two-dimensional temperature-responsive × reversed phase liquid chromatography for the analysis of wine phenolics

Phenolic compounds are an interesting class of natural products because of their proposed contribution to health benefits of foods and beverages and as a bio-source of organic (aromatic) building blocks. Phenolic extracts from natural products are often highly complex and contain compounds covering a broad range in molecular properties. While many 1D-LC and mass spectrometric approaches have been proposed for the analysis of phenolics, this complexity inevitably leads to challenging identification and purification. New insights into the composition of phenolic extracts can be obtained through online comprehensive two-dimensional liquid chromatography (LC × LC) coupled to photodiode array and mass spectrometric detection. However, several practical hurdles must be overcome to achieve high peak capacities and to obtain robust methods with this technique. In many LC × LC configurations, refocusing of analytes at the head of the 2D column is hindered by the high eluotropic strength of the solvent transferred from the 1D to the 2D, leading to peak breakthrough or broadening. LC × LC combinations whereby a purely aqueous mobile phase is used in the 1D and RPLC is used in the 2D are unaffected by these phenomena, leading to more robust methods. In this contribution, the combination of temperature-responsive liquid chromatography (TRLC) with RPLC is used for the first time for the analysis of phenolic extracts of natural origin to illustrate the potential of this alternative combination for natural product analyses. The possibilities of the combination are investigated through analysis of wine extracts by TRLC × RPLC-DAD and TRLC × RPLC-ESI-MS.

Potential Benefits of Berry Anthocyanins on Vascular Function.

Cardiovascular disease (CVD), such as hypertension and atherosclerosis, is the leading cause of global death. Endothelial dysfunction (ED) is a strong predictor for most CVD making it a therapeutic target for both drug and nutrition interventions. It has been previously shown that polyphenols from wine and grape extracts possess vasodilator activities, due to the increased expression and phosphorylation of the endothelial nitric oxide synthase (eNOS), and consequent vasodilator nitric oxide (NO) production. This is vital in the prevention of ED, as NO production contributes to the maintenance of endothelial homeostasis. Moreover, polyphenols have the ability to inhibit reactive oxygen species (ROS), which can cause oxidative stress, as well as suppress the upregulation of inflammatory markers within the endothelium. However, while the majority of the research has focused on red wine, this has overshadowed the potential of other nutritional components for targeting ED, such as the use of berries. Berries are high in anthocyanin flavonoids a subtype of polyphenols with studies suggesting improved vascular function as a result of inducing NO production and reducing oxidative stress and inflammation. This review focuses on the protective effects of berries within the vasculature.

Pyranoanthocyanins Interfering with the Quorum Sensing of Pseudomonas aeruginosa and Staphylococcus aureus.

Bacterial quorum sensing (QS) is a cell-cell communication system that regulates several bacterial mechanisms, including the production of virulence factors and biofilm formation. Thus, targeting microbial QS is seen as a plausible alternative strategy to antibiotics, with potentiality to combat multidrug-resistant pathogens. Many phytochemicals with QS interference activity are currently being explored. Herein, an extract and a compound of bioinspired origin were tested for their ability to inhibit biofilm formation and interfere with the expression of QS-related genes in Pseudomonas aeruginosa and Staphylococcus aureus. The extract, a carboxypyranoanthocyanins red wine extract (carboxypyrano-ant extract), and the pure compound, carboxypyranocyanidin-3-O-glucoside (carboxypyCy-3-glc), did not cause a visible effect on the biofilm formation of the P. aeruginosa biofilms; however, both significantly affected the formation of biofilms by the S. aureus strains, as attested by the crystal violet assay and fluorescence microscopy. Both the extract and the pure compound significantly interfered with the expression of several QS-related genes in the P. aeruginosa and S. aureus biofilms, as per reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results. Indeed, it was possible to conclude that these molecules interfere with QS at distinct stages and in a strain-specific manner. An extract with anti-QS properties could be advantageous because it is easily obtained and could have broad, antimicrobial therapeutic applications if included in topical formulations.

Assessment of Antioxidant and Antimutagenic Properties of Red and White Wine Extracts In Vitro.

Wine is an alcoholic beverage of complex composition obtained through the fermentation of grape must. The consumption of wine has already been associated with a multitude of beneficial effects due to its high polyphenolic content. In this study, four Greek emblematic wines from two red (i.e., Xinomavro and Agiorgitiko) and two white (i.e., Assyrtiko and Malagouzia) varieties were analyzed for the estimation of their antioxidant profiles. To address this question, we assessed their ability to scavenge both synthetic and endogenous free radicals, such as DPPH•, ABTS+•, OH•, O2−, their potential reducing power, and their antimutagenic and antigenotoxic properties. All varieties exhibited potent antioxidant activity, as indicated by the results of methods above, with the red wines appearing more effective than the white ones regarding antioxidant capacity. Our small-scale study is the first to reveal that these wine varieties may have the ability to scavenge the most reactive endogenous radicals. In the future, this finding must be accompanied by larger studies to fill a knowledge gap in the scientific literature concerning a holistic approach of the in vitro antioxidant action of plant polyphenolic compounds. Conclusively, we believe that wines possess high bioactivity that allow them to settle in the industry of food additives and medicinal products.

Insights on the role of acetaldehyde and other aldehydes in the odour and tactile nasal perception of red wine

Wine models with or without a dearomatised and lyophilized red wine extract containing a young red aroma base (control) plus one vector with one or several aroma compounds (unsaturated-aldehydes, saturated-aldehydes, benzaldehyde, isoamyl-alcohol, methoxypyrazines and (Z)-1,5-octadien-3-one) were prepared. Models were spiked with increasing amounts of acetaldehyde whose headspace concentrations were controlled. Odour and nasal chemesthesic properties were assessed by a trained sensory panel.Results confirm the contribution of the different players, notably isoamyl-alcohol, (Z)-1,5-octadien-3-one, benzaldehyde and methoxypyrazines, to wine aroma and tactile nasal characteristics and demonstrate that acetaldehyde levels play an outstanding role in their modulation. At low levels, it can play positive roles in some specific aromatic contexts, while at higher levels, enhance the negative effects associated to the generic presence of other aldehydes (saturated, unsaturated and Strecker aldehydes) by enhancing “green vegetable” notes and “itching” character and the “burning” effects linked to high levels of isoamyl alcohol.

Characterization of the medium infrared spectra of polyphenols of red and white wines by integrating FT IR and UV–Vis spectral data

Infrared spectroscopy is widely applied in the wine sector. The medium infrared (MIR) spectral region between 1800 and 900 cm-1 is very informative for polyphenols. Aim of this work was to perform an in-depth analysis of this spectral region of polyphenolic wine extracts. To this goal evolution of the polyphenolic fractions of white (Vermentino) and red (Cannonau) typical Sardinian wines was studied during wine-making. Wine polyphenolic extracts, obtained by solid phase extraction, were analyzed by Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) and UV–Vis spectroscopy. Spectral data from the two techniques were integrated and results depicted as Heat Map of the correlation coefficient values allowing a more accurate characterization of the MIR fingerprint region. For Cannonau, correlations between absorptions in the 420–650 and 380 nm visible spectral ranges allowed assignment of MIR peaks to anthocyanins (1016 and 1198 cm-1) and flavonols (1159 and 1277 cm-1), respectively. In Vermentino we identified MIR bands due to non-flavonols and others arising from flavonols (1376 and 1407 cm-1), present in this white wine where vinification allows short time contact with grape skins. During time, intensities of MIR bands at lower frequencies assigned to the sugar moiety of glycosylated phenols decreased in both wines.

Effect of Structural Transformations on Precipitability and Polarity of Red Wine Phenolic Polymers

Condensed tannins and polymeric pigments are essential red wine components that contribute to color stability, taste, and mouthfeel. Phenolic polymers in red wine consist of flavan-3-ol monomers and anthocyanins and cause the perception of astringency. Due to the chemical heterogeneity of proanthocyanidin polymers, analytical tools to determine the polymers’ structural features are limited. Incorporation of anthocyanins increases the structural complexity even more and makes it almost impossible to assess the influence of structure on the perceived astringency. To better understand the structural diversity of red wine polymers, this study combines forced aging and FLASH-fractionation of polyphenolic wine extracts to reveal the relationship between phenolic polymers and two physicochemical properties: polarity and hydrophilicity. Red wine fractions were characterized using polarity, the octanol-water partitioning coefficient, protein precipitation assay, ultra high-performance liquid chromatography-mass spectrometry, and color. Tannin concentrations in wine decreased during forced aging and were constant in the corresponding extracts, suggesting alteration of the precipitation behavior. A simultaneous increase in precipitable polymeric pigments leads to the assumption that incorporating anthocyanins into tannin molecules alters their interactions with red wine polysaccharides and proteins, lowering tannin readings. Finding tannins and polymeric pigments in different FLASH-fractions indicates that precipitability of polymers is affected by their physicochemical properties, which in turn depend on the degree of polymerization as well as degree of pigmentation. The results of this study show that red wine astringency and its sub-qualities may be related to the increase in precipitable polymeric pigments during forced red wine aging and their putative enhanced interaction with wine polysaccharides, increasing understanding of astringency mechanisms.

Identifying a Role of Red and White Wine Extracts in Counteracting Skin Aging: Effects of Antioxidants on Fibroblast Behavior.

Dermal fibroblasts are the main actor in many proteins’ secretion, including collagen, preserving skin function. Free radicals are involved in skin aging and damages involving different cellular components. The imbalance between reactive oxygen species (ROS) amount and natural antioxidant enzymes negatively affects skin homeostasis. Natural compounds have recently emerged as a potential anti-aging tool in tissue regeneration. In the present paper we evaluated the antioxidant activity of white and red wines, considering their probable use, as raw materials, for the formulation of cosmetic products with anti-aging properties. We studied a method that would allow the removal of the alcoholic fraction of wines and determined their composition by LC-MS analysis. We then tested the possible cytotoxic effects of red and white wines on fibroblasts by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, and their antioxidant activity by the catalase activity test in stressing conditions. Finally, we evaluated their anti-aging potential through the β-galactosidase colorimetric assay. Our results showed that wine extracts exhibit a remarkable antioxidant and anti-aging activity, especially on cells exposed to a marked stressful event. These properties could suggest their possible application as cosmetical products for skin regeneration.

Kinetics of Formation of Flavano‐C‐Glycosidic Ellagitannins (Acutissimin A and B) in Model Solutions Containing Medium Toasted Oak Chips and Catechin for Wine Aging

AbstractThe aging process of wine goes beyond conservation and involves the use of wood, which is capable of containing and protecting, and allows a limited passage of oxygen, sufficient to promote slow maturation of the wine, thanks to which it reaches the maximum of its organoleptic qualities. The most used wood is oak and during aging, the wine extracts from the wood of the barrels an abundant quantity of aromatic substances, due to the contact between the wine and the matrix of the wood. Among the newly formed compounds, the flavano‐ellagitannins, namely the acutissimin A and B, are the minor compounds found in wood aged wine. They are formed during the aging process through the condensation of tannins, such as vescalagin, extracted from the wood matrix and flavonoids, such as catechins contained in wine. The aim of the study is to verify the formation of acutissimins after 28 days in model solutions that simulated aged wine in the presence of 1%, 5%, and 10% w/v percentages of wood chips obtained from Quercus alba and with variable concentrations of catechin (100 and 500 mg L−1). The formation of compounds, including acutissimin A and B, and the disappearance of catechin are identified by high‐performance liquid chromatography/electrospray ionization/mass spectrometry. Acutissimins A and B are validated by comparison with the characteristic m/z reported in the literature. Based on the results obtained, the model system prepared with 500 mg L−1 of catechin and 10% w/v oak chips showed the highest content of acutissimin A and B.

HPLC-DAD-MS and Antioxidant Profile of Fractions from Amontillado Sherry Wine Obtained Using High-Speed Counter-Current Chromatography.

In the present work, the polyphenolic profile of a complex matrix such as Amontillado sherry has been processed by means of high-speed counter-current chromatography (HSCCC) and characterized by HPLC-DAD-MS. An Amberlite XAD-7 column was used to obtain the wine extract, and three different biphasic solvent systems were applied for HSCCC separation: MTBE (methyl tert-butyl ether)/n-butanol/acetonitrile/water (1.1/3/1.1/5+0.1% trifluoroacetic acid), MTBE/n-butanol/acetonitrile/water (2/2/1/5), and hexane/ethyl acetate/ethanol/water (1/5/1/5). As a result, 42 phenolic compounds and furanic derivatives have been identified by means of HPLC-DAD-MS, with 11 of them being identified for the first time in Sherry wines: 3-feruloylquinic acid, isovanillin, ethyl vanillate, furoic acid, dihydro-p-coumaric acid, 6-O-feruloylglucose, ethyl gallate, hydroxytyrosol, methyl protocatechuate, homoveratric acid and veratraldehyde. In addition, the antioxidant capacity (ABTS) of the obtained fractions was determined, revealing higher values in those fractions in which compounds such as gallic acid, protocatechuic acid, protocatechualdehyde, trans-caftaric acid, syringic acid, isovanillin or tyrosol, among others, were present. This is the first time that HSCCC has been used to characterize the phenolic composition of Sherry wines.

Značaj polifenola u prevenciji hroničnih nezaraznih bolesti

Polyphenols are compounds that contain in their structure one or more hydroxyl groups attached directly to one or more aromatic hydrocarbons. They represent one of the most numerous and widespread groups of secondary plant metabolites with more than 8000 polyphenolic structures. Polyphenols are antioxidants that reduce endothelial dysfunction and blood pressure, improve the immune defense, alleviate the inflammatory response, block platelet aggregation and oxidation of low-density lipoproteins. Some studies suggest that there is an indirect link between flavonoid intake and myocardial infarction and coronary heart disease. Dark chocolate, nuts, grapes, red wine and the Mediterranean diet (based on fruits and vegetables, fish and olive oil) are rich in polyphenols and are key in preventing cardiovascular disease. Polyphenols prevent neurodegenerative changes associated with cerebral ischemia. Blueberry anthocyanins have antiatherogenic and anti-inflammatory properties so they have a neuroprotective effect. Red wine extract, rich in anthocyanin, reduces injuries caused by cerebral ischemia. Food intake of polyphenols can reduce hypertension, anti-inflammatory and antioxidant effects, as well as increased production of nitric oxide. The importance of black and green tea in lowering blood pressure is especially pointed out. Further research on polyphenols is needed in order to make as clear recommendations as possible for their general preventive use.