Valuable Polyphenolic Antioxidants from Wine Vinasses

The phenolic compounds from white wine vinasses were concentrated following a patent pending process. From 1?L of wine vinasses up to 42?g of a dry product, containing 45% d.w. phenolics, could be obtained. The antioxidant activity of wine vinasse product was characterized for the reducing ability and for the scavenging capacity on non-biological radicals (DPPH^· and ABTS^·+), on the reactive oxygen species superoxide radical, peroxyl radical, H₂O₂, singlet oxygen, hypochlorous acid and on the reactive nitrogen species, nitric oxide, and peroxynitrite. The ability of the product to protect biological systems was preliminary evaluated through the protection against the ??-carotene oxidation in emulsion and the lysis and lipid peroxidation induced by APPH in erythrocytes. The product showed activity comparable to that of standard compounds (ascorbic acid, butylhydroxyanisol, butylhydroxytoluene, lipoic acid, rutin, quercetin, Tiron, Trolox) and could be proposed as a food antioxidant. The absence of skin-irritant effects on reconstructed human tissues (Episkin?) showed that this product at 1% appear to be safe for topical use in cosmetic applications.     

Free radical scavenging effect of anthocyanins in red wines

Free radicals are extremely harmful to living organisms in that, they attack different constituents of the cell, leading to acceleration of the ageing process and sometimes even its destruction, or if the DNA is affected, irreversible malfunctions. It is now widely recognised that the phenolic compounds of wine have very high free radical scavenging potential. The aim of this paper is to determine which of these phenolic compounds are responsible for the strong free radical scavenging potential of red wines. In order to do so, a red wine was fractionated into phenolic fractions. After extraction and purification of these compounds from the wine, we have measured their free radical scavenging activities using an enzymatic method. The anthocyanic fraction showed a high free radical scavenging power in relation to the other tannic fractions. In order to explain this phenomenon, some pure anthocyanins were studied and a relationship between their free radical scavenging activity and their molecular structure was suggested.     

Electron spin resonance spectroscopy studies on the free radical scavenging activity of wine anthocyanins and pyranoanthocyanins

Anthocyanins are a group of natural occurring pigments responsible for the red-blue color of grapes and many fruits and vegetables. Anthocyanins and derived pigments are of double interest, one technological, as they can be used as natural colorants, and another one due to their implication on human health through their antioxidant activity. Although there are numerous studies regarding the antioxidant activity of grape extracts as well as red wine, the free radical scavenging activity of purified anthocyanins and pyranoanthocyanins is largely unknown. In the present study, the hydroxyl and superoxide anion scavenging activities of anthocyanins and their pyruvic acid adducts were systematically investigated by electron spin resonance spectroscopy and spin trapping. The 3-glucosides of delphinidin, cyanidin, petunidin, pelargonidin and malvidin, and the pyruvic adduct of the 3-glucoside of delphinidin exhibited a potent superoxide anion radical scavenging and, to a lesser extent hydroxyl anion radical scavenging activity. The pyranoanthocyanins of cyanidin, petunidin, malvidin and pelargonidin showed a high capacity to scavenge superoxide anion radicals but did not scavenge hydroxyl radicals. Current data indicate that formation of anthocyanin adducts with pyruvic acid, which may occur during wine ageing or fruit juice processing, decreases the hydroxyl and superoxide anion scavenging and thus could decrease the antioxidant potential of these compounds.     

Singlet Oxygen Detection Using Red Wine Extracts as Photosensitizers

Moderate consumption of red wine provides beneficial effects to health. This is attributed to polyphenol compounds present in wine such as resveratrol, quercetin, gallic acid, rutin, and vanillic acid. The amount of these antioxidants is variable; nevertheless, the main beneficial effects of red wine are attributed to resveratrol. However, it has been found that resveratrol and quercetin are able to photosensitize singlet oxygen generation and conversely, gallic acid acts as quencher. Therefore, and since resveratrol and quercetin are some of the most important antioxidants reported in red wines, the aim of this research was to evaluate the photosensitizing ability of 12 red wine extracts through photo‐oxidation of ergosterol. The presence of ¹O₂ was detected by ergosterol conversion into peroxide of ergosterol through ¹H NMR analysis. Our results showed that 10 wine extracts were able to act as photosensitizers in the generation of singlet oxygen. The presence of ¹O₂ can damage other compounds of red wine and cause possible organoleptic alterations. Finally, although the reaction conditions employed in this research do not resemble the inherent conditions in wine making processing or storing, or even during its consumption, this knowledge could be useful to prevent possible pro‐oxidant effects and avoid detrimental effects in red wines.     

Sulphite-binding power of wines and ciders. II. Theoretical consideration and calculation of sulphite-binding equilibria

The Law of Mass Action is used to explain the SO₂-binding behaviour of carbonyl compounds in wines and ciders and to calculate the contribution of each carbonyl compound to the SO₂-binding power of the system. On a model wine the calculated graph of bound SO₂ with increasing concentration of free SO₂ agreed closely with experimental determinations. Fractionation of the model wine on a column of Dowex 1 (bisulphite) gave good recoveries (95 to 103.5%) of the individual components.     

Phenolics,Aroma Profile,and In Vitro Antioxidant Activity of Italian Dessert Passito Wine from Saracena (Italy)

A traditional sweet dessert wine from Saracena (Italy), made with nonmacerated local white grapes (Guarnaccia, Malvasia and Moscato), was analyzed for phenolics and aroma profile and antioxidant activities. The most abundant classes of phenols identified by high‐performance liquid chromatography were hydroxybenzoic acids and flavan‐3‐ols, where gallic acid showed the highest content (376.5 mg/L). The analysis by solid phase microextraction‐gas chromatography‐mass spectrometry revealed the presence of superior alcohols (from iso‐butanol and iso‐amyl alcohol up to 2‐phenylethanol) and their ethyl esters, terpenes (such as linalool), furfuryl compounds, and free fatty acids (up to palmitic acid) as the key odorants of this wine. The antioxidant activity, evaluated by different in vitro assays 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid (ABTS), and β‐carotene bleaching test), showed that passito wine had a radical scavenging activity (IC₅₀ value of 0.03 v/v against DPPH·) and inhibited linoleic acid oxidation with an IC₅₀ value of 0.4 v/v after 30 min of incubation.     

HPLC-DAD–MS/MS characterization of phenolic compounds in white wine stored without added sulfite

The oxidation of dihydroxybenzene and hydroxycinnamate compounds generates unstable quinones which undergo further reactions to combine nucleophilic compounds. These reactions are limited when sulfur dioxide (SO₂) is used as wine preservative, as SO₂ plays an important role in reducing quinones back to their phenol form. In no sulfite-added wine, oxidation chemistry undoubtedly results changed. Therefore, in this work, the phenolic profile of a white wine without adding sulfites, after twelve-month storage, was investigated by HPLC-DAD-MS/MS and compared to a control stored with sulfur dioxide. A total of twenty-six phenolics were detected including hydroxycinnamate derivatives and minor compounds resulting from oxidation processes, i.e. oxidized caffeic acid dimers, whose structures were tentatively proposed on the basis of their UV, MS, and MS/MS typical fragmentation. The experimental evidence of these latter is described for the first time in wine stored without added sulfites, and it may contribute to get new insight in the field of wine oxidation processes.     

On-line characterization of phenolic antioxidants in fruit wines from family myrtaceae by liquid chromatography combined with electrospray ionization tandem mass spectrometry and radical scavenging detection

A screening method based on high-performance liquid chromatography (HPLC) coupled on-line to a radical scavenging detection system and mass spectrometry (MS) was used to identify and characterize antioxidant compounds in two fruit wines from the family of the Myrtaceae, Syzygium cumini and Cleistocalyx nervosum var. paniala. The active compounds were identified by comparison of retention time and mass data with the authentic standards and with the published mass spectra assisted by multi-dimension information from a liquid chromatography combined with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and a radical scavenging detection. Major antioxidants found in S. cumini wine were complicated mixture of hydrolysable tannins and the fruit acids. A trace amount of an anthocyanin, malvidin -3-o-p-coumaroyl glucoside was also found. In C. nervosum var. paniala wine, the active compounds were identified as hydrolysable tannins and their derivative i.e. caffeoylquinic acid, gallic acid, ellagic acid and methoxymethylgallate.     

Metabolism of SO₂ binding compounds by Oenococcus oeni during and after malolactic fermentation in white wine

Sulfur dioxide SO? is the key additive for the preservation of wines. Carbonyl and keto compounds in wine can bind to SO? and decrease its efficacy, resulting in higher total SO? requirements. Increased consumer demand for low sulfite and organic wines pose production challenges if SO? binders have not been properly managed during vinification. Malolactic fermentation (MLF) has been known to reduce bound SO? levels but detailed time course studies are not available. In this work, the kinetics of major SO? binding compounds and malic acid were followed during MLF in wine with 12 commercially available strains of Oenococcus oeni. Pyruvic acid, acetaldehyde and α-ketoglutaric acid were degraded to various degrees by O. oeni, but galacturonic acid was not. At the time of malic acid depletion, percent degradation of pyruvate, α-ketoglutaric acid and acetaldehyde was 49%, 14% and 30%, respectively. During MLF, the decrease in average bound SO? levels, as calculated from carbonyl metabolism, was 22%. The largest reduction in wine carbonyl content occurred in the week after completion of MLF and was 53% (107 mg/L to 34 mg/L) calculated as bound SO?. Prolonged activity of bacteria in the wines (up to 3 weeks post malic acid depletion) resulted only in reduced additional reductions in bound SO? levels. The results suggest that microbiological wine stabilization one week after malic acid depletion is an effective strategy for maximum removal of SO? binders while reducing the risk of possible post-ML spoilage by O. oeni leading to the production acetic acid and biogenic amines.     

Fermentation temperature and the phenolic and aroma profile of persimmon wine

Persimmon wine may offer nutritional and medicinal value as it contains compounds that may be beneficial to health. Product quality is impacted by fermentation and this study investigated the influence of different fermentation temperatures on the phenolic content, aroma profile and antioxidant activity of persimmon wine. Low ethanol concentration and high residual sugar content were found in wine fermented at low temperature (15°C) leading to sluggish fermentation. The majority of phenolic compounds determined by spectrophotometric and HPLC methods increased as temperature increased from 15 to 25°C, and then decreased at 30°C. However, total tannins, total flavonids and antioxidant activity, including reducing power and radical scavenging with DPPH, hydroxyl and ABTS, were enhanced by elevated temperature. For wine aroma, GC–MS demonstrated increased isoamyl alcohol, phenylethyl alcohol, acetic acid 2‐phenylethyl ester, decanoic acid ethylester and 1‐butanol‐3‐methyl‐acetate. These results provided some basic insights for the quality control and commercial development of persimmon wine. © 2018 The Institute of Brewing & Distilling     

Inhibition ofIn VitroHuman LDL Oxidation by Phenolic Antioxidants from Grapes and Wines

Current research suggests that wine contains substances that may reduce the mortality rate from coronary diseases. The oxidation of low-density lipoprotein (LDL) is thought to be a key step in the development of atherosclerosis. Phenolic fractions of a Petite Syrah wine were evaluated for their antioxidant activity in inhibiting LDL oxidation in vitro . The more active fractions contained components of the catechin family. The catechin oligomers and the procyanidin dimers (B₂, B₃, B₄, B₆, B₈) and trimers (C₁, C₂) were extracted, isolated and purified from grapes seeds. These compounds were tested for their inhibition of LDL oxidation, along with other monomeric wine phenolics. The procyanidin dimers B₂ and B₈, and trimer C₁, and the monomers catechin, epicatechin and myricetin had the highest antioxidant activity. The procyanidin dimers B₃, B₄ and C₂ and the monomers gallic acid, quercetin, caffeic acid, and rutin, and a group of compounds that included the dimer B₆, ellagic acid, sinapic acid, cyanidin had lower antioxidant activity and α-tocopherol had the least activity. Thus, the numerous phenolic compounds found in wine are potent antioxidants in inhibiting LDL oxidation in vitro .     

黄酒和竹叶青酒抗氧化活性比较

通过采用抗亚油酸过氧化活性、清除DPPH自由基活性、清除超氧阴离子活性、还原力4个指标,分为低、中、高3个剂量组、空白对照和阳性对照,对黄酒和竹叶青酒的抗氧化活性进行比较研究,并用福林-酚法测定其中酚类物质的含量。结果表明,黄酒和竹叶青酒均具有较强的抗亚油酸过氧化活性、清除自由基活性和还原能力,且均存在一定的量效关系。同时,酚类物质的测定结果表明,黄酒和竹叶青酒中酚类物质的含量分别为165.1μg/mL和85.2μg/mL,这在一定程度上解释了黄酒的抗氧化活性高于竹叶青酒。     

Phenolic compounds and antioxidative properties of selected wines from the northeast of Thailand

The phenolic contents and antioxidative properties of selected wines, produced in the northeast of Thailand, were evaluated and compared, particularly those produced at Suranaree University of Technology (SUT) Farm as a case study. Nine wine varieties were used to evaluate their total phenolic content (TPC) by Folin–Ciocalteu method, free radical scavenging efficacy by DPPH method and reducing power by ferric reducing-antioxidant power (FRAP) method. The red wines had significantly higher (p < 0.05) amounts of total phenols, flavonoids and antioxidant activities (AA) compared to white wines. Capillary electrophoresis (CE) was used as a powerful and high performing tool for analysis of principal phenolic compounds in the wines. t-Resveratrol was found in Shiraz, Zinfandel and blended wine varieties. (+)-Catechin was found in all wine varieties, except in Chasselar Dore. (+)-Catechin was present in wines at a higher level than (−)-epicatechin. In red wine, gallic acid was the dominant phenolic acid found.     

Phenolic profile and free radical‐scavenging activity of Cabernet Sauvignon wines of different geographical origins from the Balkan region

BACKGROUND: The phenolic profile, determined by the relative proportions of different phenolic compounds, is characteristic for each grape variety and its corresponding wine. The aim of this study was to determine the phenolic and hydroxycinnamate acid, flavan‐3‐ol and flavonol contents and free radical‐scavenging activity of single‐cultivar (Cabernet Sauvignon) wines from selected Balkan vineyard regions by spectrophotometric methods and high‐performance liquid chromatography with photodiode array and fluorescence detection. RESULTS: The contents of phenolic compounds varied depending on the agroclimatic factors and oenological practices of the vineyard region. The antioxidant activity of wine samples was estimated by their ability to scavenge the stable 2,2′‐diphenyl‐1‐picrylhydrazyl free radical (DPPH). All wines showed high DPPH‐scavenging activity (70.03–83.53%, mean 73.76%). Significant correlations between catechin (R² = 0.8504) and quercetin (R² = 0.8488) concentrations and DPPH‐scavenging ability of the wines were found. CONCLUSION: The concentrations of the main components catechin and quercetin can be used as biochemical markers for the authentication of red grape cultivars and their corresponding single‐cultivar wines. Copyright © 2010 Society of Chemical Industry     

APPLICATION OF MULTIVARIATE STATISTICAL ANALYSES TO THE STUDY OF FACTORS AFFECTING WHITE WINE VOLATILE COMPOSITION

ABSTRACT

The influence of different storage conditions on the volatile composition of young white wine was evaluated during 1 year of storage. The wine was bottled and stored under different conditions of temperature, position and illumination. During storage, a significant increase in total content esters (mainly due to the increase in ethyl butyrate, ethyl acetate and diethyl succinate) and total content acids was detected. Also total content alcohols and carbonyl compounds decreased during storage. Storage time, temperature and illumination have a significant effect on esters content, whereas carbonyl compounds are affected by temperature, and alcohols content is affected by illumination. Stepwise linear discriminant analysis was applied to the experimental data. The results showed that the samples were well classified as a function of storage temperature. On the other hand, a certain trend was observed when the wine samples were classified according to storage time. The samples corresponding to two and four months of storage were well differentiated from the rest.

PRACTICAL APPLICATIONS

From a sensory point of view, the aroma influences greatly the quality of wines. The loss of aromatic characteristics in young white wine, as well as browning, take place over a variable period of time which ranges from one month to several years, depending on wine type and storage conditions. Assessment of possible factors affecting the useful lifespan of young white wine is of great interest for the wine making industry. Knowing the chemical composition of wine, specifically aromas, and its evolution relating to different storage and preservation conditions is an important tool in quality control.     

Volatile aroma components of Australian port wines

The volatile aroma compositions of a blended port wine, having an equivalent age of 20 years, and a 100-year-old port wine were examined by gas chromatography and gas chromatography-mass spectrometry. The compounds identified were products of yeast fermentation, acetalisation, esterification and oxidation reactions occurring during storage, carbohydrate degradation (of residual grape sugar and wood hemi-celluloses) and wood extraction. High concentrations of ethyl lactate, diethyl succinate and diethyl malate were found relative to quantities present in young wine. 1-Ethoxy-1-(3-methylbutoxy)ethane, 1-ethoxy-1-(2-methylbutoxy)ethane, 1,1-diethoxypropan-2-one, cis-5-hydroxy-2-methyl-1,3-dioxane and cis-4-hydroxymethyl-2-methyl-1,3-dioxolane were identified. The presence of these and other acetals demonstrated that carbonyl compounds were also present. Carbonyl compounds are likely to contribute to the ‘rancio’ flavour of these port wines. Carbohydrate-derived compounds found included furfural, 2-acetylfuran, 5-methylfurfural, ethyl laevulinate, ethyl furoate and 5-ethoxymethyl furfural. Oak lactone, which is a wood extractive, was also identified and is likely to contribute to the woody aroma distinguishable in these port wines.     

Updated knowledge about the presence of phenolic compounds in wine

Phenolic compounds are partly responsible for the color, astringency, and bitterness of wine, as well as for numerous physiological properties associated with wine consumption. Mass spectrometry has allowed for great progress in the identification and characterization of wine polyphenols. The aim of the present article is to summarize the numerous advances recently achieved in this field. The main type of phenolic compounds found in wine, including hydroxybenzoic and hydroxycinnamic acids, stilbenes, flavones, flavonols, flavanonols, flavanols, and anthocyanins, are firstly described. Chemical reactions and mechanisms involving phenolic compounds during winemaking are also extensively discussed, including enzymatic and chemical oxidation reactions, direct and acetaldehyde-mediated anthocyanin-tannin condensation reactions, acetaldehydemediated and glyoxylic acid-mediated tannin-tannin condensation reactions and, C-4/C-5 anthocyanin cycloaddition reactions with 4-vinylphenols, vinylflavanols and pyruvic acid, among others, leading to the formation of pyranoanthocyanins. Useful mass spectral data of well-known and novel phenolic compounds recently identified in wine, and details related to their fragmentation pathway according to different ionization techniques, are given.     

Antioxidant properties of resveratrol: A structure–activity insight

Resveratrol, a natural product, is known to affect a broad range of intracellular mediators. In the present study, we clarified the antioxidant activity of resveratrol by employing various in vitro antioxidant assays such as DPPH?, ABTS^?+, DMPD^?+, O₂^?? and H₂O₂ scavenging activities, total antioxidant activity, reducing abilities, and Fe²⁺ chelating activities. Resveratrol inhibited 89.1% of the lipid peroxidation of linoleic acid emulsion at 30 µg/mL concentration. On the other hand, BHA, BHT, α-tocopherol, and trolox exhibited inhibitions of 83.3, 82.1, 68.1, and 81.3% against peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, resveratrol had effective DPPH?, ABTS^?+, DMPD^?+, O₂^?? and H₂O₂ scavenging activities, reducing power, and Fe²⁺ chelating activities. The present study found that resveratrol had effective in vitro antioxidant and radical scavenging activity. It can be used in pharmacological and food industry due to its antioxidant properties.Industrial relevanceAntioxidants are often added to foods to prevent the radical chain reactions of oxidation and they act by inhibiting the initiation and propagation step leading to the termination of the reaction and delay the oxidation process. At the present time, the most commonly used antioxidants are BHA, BHT, propylgallate and tert-butyl hydroquinone. Besides that BHA and BHT are restricted by legislative rules because of doubts over their toxic and carcinogenic effects. Therefore, there is a growing interest on natural and safer antioxidants in food applications, and a growing trend in consumer preferences for natural antioxidants, all of which has given more impetus to explore natural sources of antioxidants. A variety of foods and beverages of vegetable origin contain several nonflavonoid classes of phenolic compounds synthesized by plants. Among them, resveratrol has been identified as the major active compound of stilbene phytoalexins and is presumed to be beneficial for human health. Resveratrol is naturally occurring in the fruits and leaves of edible plants, peanuts, mulberries, grapes and red wine. Resveratrol is currently in the limelight all over the world due to their beneficial effects on the human body. Resveratrol can be used for minimizing or preventing lipid oxidation in pharmaceutical products, retarding the formation of toxic oxidation products, maintaining nutritional quality and prolonging the shelf life of food products and pharmaceuticals instead of BHA and BHT and other antioxidant compounds because of their safer usage.     

Antioxidant Activities of Polyphenolic Compounds Isolated from Antidesma thwaitesianum Müll. Arg. Seeds and Marcs

ABSTRACT: Antidesma thwaitesianum Müll. Arg. or mao is widely used as commercial products of juice and wine in Thailand. As a result, waste products from the mao plant, such as mao seeds (MS) and mao marcs (MM), are plentiful. We aimed to purify and analyze polyphenolic content in both MS and MM and to investigate the radical scavenging activities of these polyphenolics against 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) and 2,2′‐Azinobis (3‐ethylbenzothiazoline 6‐sulphonate) (ABTS) radicals and thiobarbituric acid reactive products (TBARP). The results showed MS and MM to be an abundant source of polyphenols (97.32 to 130 mg gallic acid equivalents [GAE]/g) and proanthocyanidins. The radical scavenging activities of MS/MM against DPPH and ABTS radicals (IC₅₀ of 0.85 to 1.21 μg/mL) were significantly higher (P < 0.05) than that of standard trolox (IC₅₀ of 5.05 μg/mL). Activity of MS/MM extracts were 3.74 and 3.80 μg/mL trolox eq/g f.w. for the DPPH and ABTS assays, respectively. The oxidation of erythrocyte membranes using 2‐thiobarbituric acid demonstrated that the protective effect of MS/MM on lipid peroxidation is as strong as grape seed proanthocyanidin extract. These findings suggest that polyphenolic compounds and proanthocyanidins isolated from these mao extracts had much higher antioxidant activities than those of standard trolox and exhibited similar antioxidant potential to grape seed proanthocyanidin extract. These findings may also increase value of mao waste products and allow development of commercial health products.     

Chemical composition and in vitro antimicrobial and cytotoxic activities of plum (Prunus domestica L.) wine

A moderate intake of wine is associated with a positive impact on human health owing to the effects of important biologically active components present in the wine in large amounts. The aim of this study was to examine the chemical composition and to assess antimicrobial and cytotoxic activities of fruit wines produced from three plum varieties (?a?anska rana, ?a?anska lepotica and Po?ega?a) commonly grown in Serbia as an approach to assess the quality and acceptability of these wines as a functional food. Furthermore, the activity of a series of control samples was assessed in order to determine components from the wine that are responsible for its functional properties. The plum wines produced showed considerable antimicrobial activity against six bacterial and two yeast strains used in this study. In addition to antimicrobial activity, the plum wines showed a significant cytotoxic effect (IC₅₀ < 50 µg mL^?1) on the growth of three tested cancer cell lines (Hep2c, RD and L2OB). Regarding the determined activities, ?a?anska rana plum wine achieved the best results. The results indicated that the antimicrobial activity of the plum wines was, in large part, based on the effects of the total acids and the pH value, while the contribution of ethanol and the content of the phenolic compounds were not significant. Similar conclusions were drawn regarding the cytotoxic activity of this fruit wine. The results can be seen as a contribution to the global acceptance of fruit wines as a functional food, with the accent placed on moderate consumption. An important advantage of fruit wines (in particular plum wine), compared with traditional grape wine, is their lower alcohol content. Copyright © 2016 The Institute of Brewing & Distilling