Anthocyanins and antioxidant activity of red wines made from endemic grape varieties

Effect of Vinegar on the Oxidative Stability of Mayonnaise During its Storage

Mayonnaise is an emulsion of oil that is susceptible to lipid oxidation, which can cause spoilage and the formation of harmful compounds. This study aims to evaluate the impact of Syrian apple and grape vinegar on the oxidative stability of mayonnaise and compare the use of natural antioxidants to synthetic ones such as butylated hydroxyanisole and butylated hydroxytoluene. The study measured total phenol content, radical scavenging activity, and identified some phenolic compounds by High Performance Liquid Chromatography (HPLC). The rancidity of mayonnaise was examined using peroxide value and thiobarbituric acid number. The fatty acids content in the mayonnaise samples was examined using gas chromatography. Vinegar samples containing high concentrations of phenolic antioxidants showed high ability to scavenge free radicals. The antioxidants in vinegar protected the mayonnaise samples from primary and secondary oxidation, and there was no statistically significant difference between the ratio of unsaturated fatty acids in the samples containing vinegar at the beginning and at the end of the storage period. The study shows the significance of using vinegar to protect mayonnaise from deterioration and increase its shelf life, in addition to its role as a dressing.

Optimization of the method of ultrasonic extraction of lycopene with a green extract from the fruit of Elaeagnus umbellata, common in Western Georgia

The study determined the content of lycopene in the fruits of the Elaeagnus umbellata (35.25-60.21 mg/100 g), common at different heights above sea level in Western Georgia. For the effective extraction of lycopene as a biologically active substance, the optimal conditions for ultrasonic extraction were selected: sunflower oil was used as a "green solvent"; the ratio of solid mass and solvent was 1:50; temperature 30°C; ultrasound amplitude 40%; power 85 W; and extraction time 10 min. FTIR spectra revealed the characteristic functional groups of lycopene exhibiting two characteristic peaks at 2920 and 2950 cm-1. To explore the effect of lycopene on oil quality, the acid value, peroxide value, and p-anisidine were determined in each oil sample. The antioxidant determination by inhibition of DPPH radicals showed significant differences in native oils and oils with lycopene.

PANI sensor for monitoring the oxidative degradation of wine using cyclic voltammetry

Redox species in wine are altered by pH and some wines are easily degraded due to oxidation and sulfur dioxide (SO₂) reduction. There is a need for quick, easy, simple, and economical methodologies for pH and wine-oxidized products (acetaldehyde) analysis. This study aimed to measure pH and degradation of wines that were electrochemically analyzed using polyaniline (PANI) sensor. Gas chromatography (GC) and fourier transform infrared spectrometer (FT-IR) were also used. Electrochemical analysis showed that oxidation was accelerated and peak currents (I_p,a) and potentials (E_p,a) shifted to negative direction due to acetaldehyde formation. PANI sensor achieved a limit of detection (LOD) of 7 × 10^-1 ppm and a sensitivity of 5.20 µA ppm^-1 cm^-2. Acetaldehyde formation was confirmed by GC (30%) and FT-IR spectra at 1647 cm^-1 to the CO vibration of aldehyde. These results suggested that acetaldehyde degraded the taste of wine after remaining open.

Food Anthocyanins: Malvidin and Its Glycosides as Promising Antioxidant and Anti-Inflammatory Agents with Potential Health Benefits

Anthocyanins are flavonoid compounds that are abundantly present in fruits and vegetables. These compounds contribute to the color of these foods and offer various health benefits to consumers due to their biological properties. There are more than 1000 types of anthocyanins in nature, all derived from 27 anthocyanidin aglycones that have different glycosylations and acylations. Malvidin is one of the most well-known anthocyanidins. Several studies, including those conducted on cell lines, animals, and humans, have suggested that malvidin and its glycosides possess anti-carcinogenic, diabetes-control, cardiovascular-disease-prevention, and brain-function-improvement properties. These health benefits are primarily attributed to their antioxidant and anti-inflammatory effects, which are influenced by the molecular mechanisms related to the expression and modulation of critical genes. In this article, we review the available information on the biological activity of malvidin and its glycosides concerning their health-promoting effects.

Behind the Scenes of Anthocyanins-From the Health Benefits to Potential Applications in Food, Pharmaceutical and Cosmetic Fields

Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains. The pigments' stability and colours are influenced mainly by pH but also by structure, temperature, and light. The colour-stabilizing mechanisms of plants are determined by inter- and intramolecular co-pigmentation and metal complexation, driven by van der Waals, π-π stacking, hydrogen bonding, and metal-ligand interactions. This group of flavonoids is well-known to have potent anti-inflammatory and antioxidant effects, which explains the biological effects associated with them. Therefore, this review provides an overview of the role of anthocyanins as natural colorants, showing they are less harmful than conventional colorants, with several technological potential applications in different industrial fields, namely in the textile and food industries, as well as in the development of photosensitizers for dye-sensitized solar cells, as new photosensitizers in photodynamic therapy, pharmaceuticals, and in the cosmetic industry, mainly on the formulation of skin care formulations, sunscreen filters, nail colorants, skin & hair cleansing products, amongst others. In addition, we will unveil some of the latest studies about the health benefits of anthocyanins, mainly focusing on the protection against the most prevalent human diseases mediated by oxidative stress, namely cardiovascular and neurodegenerative diseases, cancer, and diabetes. The contribution of anthocyanins to visual health is also very relevant and will be briefly explored.

Employ of Anthocyanins in Nanocarriers for Nano Delivery: In Vitro and In Vivo Experimental Approaches for Chronic Diseases

Anthocyanins are among the best-known phenolic compounds and possess remarkable biological activities, including antioxidant, anti-inflammatory, anticancer, and antidiabetic effects. Despite their therapeutic benefits, they are not widely used as health-promoting agents due to their instability, low absorption, and, thus, low bioavailability and rapid metabolism in the human body. Recent research suggests that the application of nanotechnology could increase their solubility and/or bioavailability, and thus their biological potential. Therefore, in this review, we have provided, for the first time, a comprehensive overview of in vitro and in vivo studies on nanocarriers used as delivery systems of anthocyanins, and their aglycones, i.e., anthocyanidins alone or combined with conventional drugs in the treatment or management of chronic diseases.

Value-Added White Beer: Influence of Red Grape Skin Extract on the Chemical Composition, Sensory and Antioxidant Properties

This work aimed to improve the functionality of beer by increasing the level of antioxidant activity through the addition, up to acceptable sensory amounts, of red grape skin extract. A commercial hefeweizen beer was supplemented with different concentrations (1, 5, and 10 mg/mL) of grape skin extract (GSE). The phytochemical characterization of GSE and supplemented beer samples was achieved in terms of the total phenolic content (TPC), total flavonoid content (TFC), and total monomeric anthocyanin content (TMA). Additionally, the antioxidant activity of the samples was assessed using a variety of radical scavenging tests. The addition of various concentrations of GSE significantly increased the TPC and TFC content of beer samples, from 3.167 to 4.477 mg GAE/mL and from 0.841 to 1.226 mg CE/mL, respectively. The TMA content of the GSE-supplemented white beer samples ranged from 0.005 to 0.027 mg C3G/ mL. Consequently, the antioxidant capacity of the beer samples increased with the level of GSE addition. The obtained results suggest the potential of using GSE as a functional ingredient for beer production.

Development of a New Strategy for Studying the Oxygen Consumption Potential of Wine through the Grape Extract Evaluation

The development of a method to determine the aging potential of wine at the time of harvest, through the evaluation of its oxygen avidity, is a potential tool for the winemaking sector. To this end, it is necessary to formulate a potential wine with this grape prior to alcoholic fermentation. The main objective of this method was to optimize a formulation of the potential wine, based on the grape extracts (GEs), to subsequently evaluate its oxygen consumption kinetics, guaranteeing maximum differentiation between the different GEs. The optimization was carried out with a Taguchi orthogonal matrix design, which optimized the variables to be used in the GE reconstitution. The variables studied were pH, Fe2+, Cu2+, Mn2+, alcohol content and acetaldehyde. The evaluation of the characteristic parameters of the consumption kinetics of each of the GEs allowed us to know the different reconstitution conditions that most influence the differentiation of the oxygen consumption kinetics of very similar GEs. The reconstitution conditions chosen were pH 3.3; 1 mg/L Fe2+; 0.1 mg/L Cu2+; 1 mg/L Mn2+; 12% (v/v) alcoholic strength and 10 mg/L acetaldehyde, with pH, Fe2+ and Mn2+ being the significant conditions. The kinetics of reconstituted GE could be a tool for the classification and evaluation of grapes according to their aging potential or shelf life of the wine made.

Quantitative Analysis of Anthocyanins in Grapes by UPLC-Q-TOF MS Combined with QAMS

A method for quantifying the anthocyanins in grapes was firstly developed by ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOFMS) combined with quantitative analysis of multi-components by single marker (QAMS). A total of 10 main anthocyanins were analyzed by using peonidin 3-O-glucoside as the reference standard. The accuracy of this method was evaluated by an established and validated external standard quantification method with 10 reference compounds. The standard method difference (SMDs) of the quantification results between QAMS and the external standard methodwasless than 15%. Furthermore, the QAMS method was used to analyzefour batches of grapes and the data was compared with those obtained using the external standard method. No significant difference wasobtained in the results obtained by both methods. These results indicated that the QAMS method could accurately determine the anthocyanins in grapes. This method can provide a basis to address the absence of reference standards for analyzing anthocyanins in other foods.

Changes in the antioxidant activity of red dry wines depending on the production method

It is found that a production method affects the antioxidant activity of researched red dry wines made grapes produced in Kuban area. According to results of multivariate analysis of variance, grape variety (59% of influence), production method (27%) and usage of antioxidants during must extraction (7%) influenced on antioxidant activity values.

Development and Characterization of Arrowroot Starch Films Incorporated with Grape Pomace Extract

Grape processing residues are a good source of bioactive and nutritional compounds. The incorporation of grape pomace extract (GPE) in starch films can be a strategy for the elaboration of new food packaging products for applications such as edible films or fruit strips. In this context, the objective of this research was to analyze the effect of incorporation and variation of concentration of GPE (0, 20, 30, and 40% mass/mass starch solids) on the physical chemical properties of arrowroot starch edible films created by casting. The GPE was characterized for moisture content, pH, total titratable acidity, total soluble solids, and anthocyanin content. Starch films with and without GPE were evaluated by analyzing their visual appearance, water activity, water content, thickness, water solubility, and water vapor permeability. The GPE had high water content, acidity, and anthocyanins content. The films with GPE showed a noticeable reddish color, similar to observed for the GPE. Increasing the concentration of GPE in the film resulted in significantly increased (p < 0.05) thickness (from 0.060 to 0.106 mm), water content (from 8.17 to 12.48%), solubility in water (from 13.33 to 33.32%), and water vapor permeability (from 3.72 to 6.65 g.mm/m2 day kPa). GPE increased the hydrophilic portion of the film, in addition to acting as a plasticizer, decreasing the molecular interactions of the polymer chain, and favoring its solubilization, which is desirable for applications such as edible films. The elaboration of arrowroot starch films with the incorporation of grape pomace is a good alternative for the reduction of by-products of grape processing.

Thermal Stability and Inhibitory Action of Red Grape Skin Phytochemicals against Enzymes Associated with Metabolic Syndrome

The present study focuses on heat-induced structural changes and the degradation kinetics of phytochemicals and antioxidant activity of red grape skin extract. The thermal degradation of anthocyanins, flavonoids, polyphenols, and antioxidant activity followed a first-order kinetic model, increasing with temperature due to the intensification of the degradation process. The activation energy (Ea) highlighted this phenomenon. Likewise, the kinetic and thermodynamic parameters certified the irreversible degradation of the bioactive compounds from the skin of the Băbească neagră grape variety. Both temperature and duration of heating had a significant impact on the content of bioactive compounds. In addition, the red grape skin extract inhibited certain enzymes such as α-amylase, α-glucosidase, lipase, and lipoxygenase, which are associated with metabolic syndrome and inflammation. Further knowledge on the possible inhibition mechanisms exerted by the major anthocyanins found in red grape skin extract on the metabolic syndrome-associated enzymes was gathered upon running molecular docking tests. Detailed analysis of the resulting molecular models revealed that malvidin 3-O-glucoside binds in the vicinity of the catalytic site of α-amylase and lipase, whereas no direct contact with catalytic amino acids was identified in the case of α-glucosidase and lipoxygenase.

Chemical Composition and Polyphenolic Compounds of Red Wines: Their Antioxidant Activities and Effects on Human Health—A Review

Red wine, an alcoholic beverage is composed of a spectrum of complex compounds such as water, alcohol, glycerol, organic acid, carbohydrates, polyphenols, and minerals as well as volatile compounds. Major factors that affect the levels of phenolic compounds in red wines are the variety of grapes and the storage of the wines. Among the constituents of red wine, phenolic compounds play a crucial role in attributes including color and mouthfeel and confer beneficial properties on health. Most importantly, phenolic compounds such as flavanols, flavonols, flavanones, flavones, tannins, anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and resveratrol can prevent the development of cardiovascular diseases, cancers, diabetes, inflammation, and some other chronic diseases.

Analysis of aroma and polyphenolic compounds in Saperavi red wine vinified in Qvevri

The purpose of this study is to analyze and characterize a Georgian red wine from Saperavi grape, obtained in Qvevri (Georgian traditional winemaking method), by using innovative techniques for the determination of the polyphenolic content, aroma, and its correlation to the sensory characteristics. This peculiar red wine, after high-performance liquid chromatography with diode-array detection and mass spectrometry (HPLC-DAD-MS), headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and HS-SPME-GCxGC-MS/TOF (two-dimensional gas chromatography) chemical characterization showed a high polyphenol content (19.6 × 102 mg/L, 38.4% anthocyanins) and a wide range of volatile compounds, among which terpenes were associated with the aroma of flowers, lemongrass, and wood. Analyses were also conducted to determine the total polyphenol content correlated to antioxidant activity with the Folin-Ciocalteu spectrophotometric in vitro method (4.650 g GAE/L). In conclusion, for the first time on Saperavi wine, innovative techniques such as HPLC-DAD-MS, GC-MS, and GCxGC-MS/TOF were simultaneously applied in association with the traditional analytic techniques to perform a complete chemical characterization. These activities are part of a project about circular viticulture in the Georgian territory that will lead the production of traced quality wines and the valorization of the Georgian wine sector.

Dietary Effects of Anthocyanins in Human Health: A Comprehensive Review

In recent years, the consumption of natural-based foods, including beans, fruits, legumes, nuts, oils, vegetables, spices, and whole grains, has been encouraged. This fact is essentially due to their content in bioactive phytochemicals, with the phenolic compounds standing out. Among them, anthocyanins have been a target of many studies due to the presence of catechol, pyrogallol, and methoxy groups in their chemical structure, which confer notable scavenging, anti-apoptotic, and anti-inflammatory activities, being already recommended as supplementation to mitigate or even attenuate certain disorders, such as diabetes, cancer, and cardiovascular and neurological pathologies. The most well-known anthocyanins are cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside. They are widespread in nature, being present in considerable amounts in red fruits and red vegetables. Overall, the present review intends to discuss the most recent findings on the potential health benefits from the daily intake of anthocyanin-rich foods, as well as their possible pharmacological mechanisms of action. However, before that, some emphasis regarding their chemical structure, dietary sources, and bioavailability was done.

A review of the interaction between anthocyanins and proteins

Anthocyanins have good physiological functions, but they are unstable. The interaction between anthocyanins and proteins can improve the stability, nutritional and functional properties of the complex. This paper reviews the structural changes of complex of anthocyanins interacting with proteins from different sources. By circular dichroism (CD) spectroscopy, it was found that the contents of α-helix (from 15.90%-42.40% to 17.60%-52.80%) or β-sheet (from 29.00%-50.00% to 29.40%-57.00%) of the anthocyanins-proteins complex increased. Fourier transform infrared spectroscopy showed that the regions of amide I (from 1627.87-1641.41 cm^-1 to 1643.34-1651.02 cm^-1) and amide II (from 1537.00-1540.25 cm^-1 to 1539.00-1543.75 cm^-1) of anthocyanins-proteins complex were shifted. Fluorescence spectroscopy showed that the fluorescence intensity of the complex decreased from 150-5100 to 40-3900 a.u. The thermodynamic analysis showed that there were hydrophobic interactions, electrostatic and hydrogen bonding interactions between anthocyanins and proteins. The kinetic analysis showed that the half-life and activation energy of the complex increased. The stability, antioxidant, digestion, absorption, and emulsification of the complex were improved. This provides a reference for the study and application of anthocyanins and proteins interactions.