First evidence of epicatechin vanillate in grape seed and red wine

A Review on Wine Flavour Profiles Altered by Bottle Aging

The wine flavour profile directly determines the overall quality of wine and changes significantly during bottle aging. Understanding the mechanism of flavour evolution during wine bottle aging is important for controlling wine quality through cellar management. This literature review summarises the changes in volatile compounds and non-volatile compounds that occur during wine bottle aging, discusses chemical reaction mechanisms, and outlines the factors that may affect this evolution. This review aims to provide a deeper understanding of bottle aging management and to identify the current literature gaps for future research.

Biological and pharmacological aspects of tannins and potential biotechnological applications

Secondary metabolites are divided into three classes: phenolic, terpenoid, and nitrogenous compounds. Phenolic compounds are also known as polyphenols and include tannins, classified as hydrolysable or condensed. Herein, we explored tannins for their ROS reduction characteristics and role in homeostasis. These activities are associated with the numbers and degree of polymerisation of reactive hydroxyl groups present in the phenolic rings of tannins. These characteristics are associated with anti-inflammatory, anti-aging, and anti-proliferative health benefits. Tannins can reduce the risk of cancer and neurodegenerative diseases, such as cardiovascular diseases and Alzheimer's, respectively. These biomolecules may be used as nutraceuticals to maintain good gut microbiota. Industrial applications include providing durability to leather, anti-corrosive properties to metals, and substrates for 3D printing and in bio-based foam manufacture. This review updates regarding tannin-based research and highlights its biological and pharmacological relevance and potential applications.

Vitis vinifera (Vine Grape) as a Valuable Cosmetic Raw Material

This review refers to botanical, ecological and phytochemical characteristics of Vitis vinifera L. (vine grape)-a species, the valuable properties of which are widely exploited in the food industry and in recent times in medicine as well as in phytocosmetology. The general characteristic of V. vinifera, followed by the chemical composition and biological activities of different extracts obtained from the plant (fruit, skin, pomace, seed, leaf and stem extracts), are provided. A concise review of the extraction conditions of grape metabolites and the methods of their analysis are also presented. The biological activity of V. vinifera is determined by the presence of high contents of polyphenols, mainly flavonoids (e.g., quercetin, kaempferol), catechin derivatives, anthocyanins and stilbenoids (e.g., trans-resveratrol, trans-ε-viniferin). The review pays particular attention to the application of V. vinifera in cosmetology. It has been proven that V. vinifera possesses strong cosmetological-related properties, such as anti-ageing properties, anti-inflammatory properties and skin-whitening properties. Moreover, a review of studies on V. vinifera biological activities, which are of particular interest for dermatologic problems, are disclosed. Furthermore, the work also emphasises the importance of biotechnological studies on V. vinifera. The last part of the review is addressed to the safety of the use of V. vinifera.

Accelerated Solvent Extraction of Phenols from Lyophilised Ground Grape Skins and Seeds

The efficient extraction of phenols from grapes is an important step for their reliable quantification. The aim was to optimise the lyophilisation process and the extraction of phenols from grape skins and seeds. The phenol extraction yield from lyophilised tissues was investigated with different accelerated solvent extraction (ASE) operating conditions. Skins and seeds were separated from frozen berries and lyophilised without being ground. The weight loss during lyophilisation was followed daily. Phenols were extracted from lyophilised, cryo-ground seeds and skins with ASE at room temperature and 10.3 MPa using 80% aqueous acetone and 60% aqueous methanol. The effects of ASE operational parameters (the number of extraction cycles (ECs) and static time (ST) duration) were investigated. The yield of extracted phenols was evaluated spectrophotometrically by determining total phenolic index at 280 nm (TPI). The weight of skins and seeds significantly dropped after 24 h of lyophilisation and continued to decrease, although not significantly, up until the 9th day. The optimal lyophilisation time was estimated to be 3 days and 5 days for skins and seeds, respectively. The phenol extraction yield was significantly affected after changes of ASE conditions. Based on TPI, the optimal ASE conditions were as follows: (i) lyophilised seeds—eight ECs with 10 min ST using aqueous acetone and then four ECs with 20 min ST using aqueous methanol; (ii) lyophilised skins—eight ECs with 1 min ST using aqueous acetone and then one EC with 20 min ST using aqueous methanol.

Chemical Diversity of Flavan-3-Ols in Grape Seeds: Modulating Factors and Quality Requirements

Grape seeds are a rich source of flavan-3-ol monomers, oligomers, and polymers. The diverse profile of compounds includes mainly B-type procyanidins (especially C4→C8 linked molecules) and the key monomers, catechin, and epicatechin that are positively implicated in the 'French Paradox'. Today grape seed nutraceuticals have become a multi-million-dollar industry. This has created incentives to elucidate the variations in chemistry across cultivars, to identify signs of adulteration, and to understand the intrinsic and extrinsic factors controlling the expression of metabolites in the seeds' metabolome. This review provides a critical overview of the existing literature on grape seed chemistry. Although the biosynthetic pathways for polymeric procyanidins in seeds have not yet been explained, abiotic factors have been shown to modulate associated genes. Research of extrinsic factors has demonstrated that the control of procyanidin expression is strongly influenced, in order of importance, by genotype (species first, then variety) and environment, as claimed anecdotally. Unfortunately, research outcomes on the effects of abiotic factors have low certainty, because effects can be specific to genotype or variety, and there is limited control over physical metrics in the field. Thus, to gain a fuller understanding of the effects of abiotic factors and biosynthetic pathways, and realise potential for optimisation, a more fundamental research approach is needed. Nevertheless, the current synthesis offers insight into the selection of species or varieties according to the profile of polyphenols, as well as for optimisation of horticultural practices, with a view to produce products that contain the compounds that support health claims.

Metabolomic Analysis Reveals Nutritional Diversity among Three Staple Crops and Three Fruits

More than 2 billion people worldwide are under threat of nutritional deficiency. Thus, an in-depth comprehension of the nutritional composition of staple crops and popular fruits is essential for health. Herein, we performed LC-MS-based non-targeted and targeted metabolome analyses with crops (including wheat, rice, and corn) and fruits (including grape, banana, and mango). We detected a total of 2631 compounds by using non-targeted strategy and identified more than 260 nutrients. Our work discovered species-dependent accumulation of common present nutrients in crops and fruits. Although rice and wheat lack vitamins and amino acids, sweet corn was rich in most amino acids and vitamins. Among the three fruits, mango had more vitamins and amino acids than grape and banana. Grape and banana provided sufficient 5-methyltetrahydrofolate and vitamin B6, respectively. Moreover, rice and grape had a high content of flavonoids. In addition, the three crops contained more lipids than fruits. Furthermore, we also identified species-specific metabolites. The crops yielded 11 specific metabolites, including flavonoids, lipids, and others. Meanwhile, most fruit-specific nutrients were flavonoids. Our work discovered the complementary pattern of essential nutrients in crops and fruits, which provides metabolomic evidence for a healthy diet.

Flavor Chemical Profiles of Cabernet Sauvignon Wines: Six Vintages from 2013 to 2018 from the Eastern Foothills of the Ningxia Helan Mountains in China

The eastern foothills of the Helan Mountains in the Ningxia region (Ningxia), is a Chinese wine-producing region, where Cabernet Sauvignon is the main grape cultivar; however, little compositional or flavor information has been reported on Ningxia wines. Oenological parameters, volatile profiles, and phenolic profiles were determined for 98 Ningxia Cabernet Sauvignon wines from the 2013–2018 vintages, as well as 16 from Bordeaux and California, for comparison. Ningxia wines were characterized by high ethanol, low acidity, and high anthocyanin contents. Multivariate analysis revealed that citronellol and 12 characteristic phenolic compounds distinguish Ningxia wines from Bordeaux and California wines. The concentrations of most phenolic compounds were highest in the 2018 Ningxia vintage and decreased with the age of the vintage. To our knowledge, this is the first extensive regionality study on red wines from the Ningxia region.

The Role of High-Resolution Analytical Techniques in the Development of Functional Foods

The approaches based on high-resolution analytical techniques, such as nuclear magnetic resonance or mass spectrometry coupled to chromatographic techniques, have a determining role in several of the stages necessary for the development of functional foods. The analyses of botanical extracts rich in bioactive compounds is one of the fundamental steps in order to identify and quantify their phytochemical composition. However, the compounds characterized in the extracts are not always responsible for the bioactive properties because they generally undergo metabolic reactions before reaching the therapeutic targets. For this reason, analytical techniques are also applied to analyze biological samples to know the bioavailability, pharmacokinetics and/or metabolism of the compounds ingested by animal or human models in nutritional intervention studies. In addition, these studies have also been applied to determine changes of endogenous metabolites caused by prolonged intake of compounds with bioactive potential. This review aims to describe the main types and modes of application of high-resolution analytical techniques in all these steps for functional food development.

Flavan-3-ols in Vitis seeds: Their extraction and analysis by HPLC-ESI-MS/MS

An orthogonal L₁₆4³ × 2² test design was applied to select the optimum conditions for extracting flavan-3-ols in grape seeds. Highest yield of flavan-3-ols was achieved with 80% methanol, a ratio [1:30 (g/mL)] of sample-to-solvent, sonication for 20 min, and extraction at 25 °C for 12 h in darkness. The optimized analytical method for HPLC separation was a multistep gradient elution using 1% formic acid (A) and acetonitrile containing 1% formic acid (B), at a flow rate of 0.6 mL/min in 36 min. Moreover, fourteen flavan-3-ols were separated and identified using HPLC-ESI-MS/MS, including four monomers ((+)-catechin, (-)-epicatechin, epigallocatechin gallate and epicatechin gallate) and ten oligomers (three dimers, four trimers, two tetramers and one pentamer). The optimized method was used to determine flavan-3-ols content and compositions among ten representative cultivars. The new wine grape - Beihong, had higher flavan-3-ols content and polymerization than classic wine grapes - Cabernet Sauvignon, Merlot, Semillon and Riesling.

NMR spectroscopy in wine authentication: An official control perspective

Wine authentication is vital in identifying malpractice and fraud, and various physical and chemical analytical techniques have been employed for this purpose. Besides wet chemistry, these include chromatography, isotopic ratio mass spectrometry, optical spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy, which have been applied in recent years in combination with chemometric approaches. For many years, ² H NMR spectroscopy was the method of choice and achieved official recognition in the detection of sugar addition to grape products. Recently, ¹ H NMR spectroscopy, a simpler and faster method (in terms of sample preparation), has gathered more and more attention in wine analysis, even if it still lacks official recognition. This technique makes targeted quantitative determination of wine ingredients and nontargeted detection of the metabolomic fingerprint of a wine sample possible. This review summarizes the possibilities and limitations of ¹ H NMR spectroscopy in analytical wine authentication, by reviewing its applications as reported in the literature. Examples of commercial and open-source solutions combining NMR spectroscopy and chemometrics are also examined herein, together with its opportunities of becoming an official method.

Impact of grapevine red blotch disease on primary and secondary metabolites in 'Cabernet Sauvignon' grape tissues

The grapevine red blotch disease (GRBD) was first noticed in 2008, impacting grape ripening. In general, GRBD reduces grape and wine quality resulting in significant economic losses. The purpose of the present study was to evaluate the effect of GRBD on agronomical parameters of 'Cabernet Sauvignon' vines at harvest. Using a metabolomics approach, the influence on primary and secondary metabolite profiling in skin + pulp/flesh and seeds were also determined. GRBD influenced °Brix and berry weight, as well as primary and secondary metabolites in both tissues. 1D ¹H NMR was effective in quantifying the main primary and secondary metabolites affected by GRBD. RP-HPLC was similarly able to quantify the main phenolics affected. Multivariate analysis showed the influence of the virus on grape metabolites using both tools in two berry tissues. The effectiveness of both tools to describe sample variability was compared and the most affected metabolites in each tissue could be identified.

Impact of Epicatechin on the Procoagulant Activities of Microparticles

Microparticles play a role in cardiovascular disease pathology. The flavanol-like epicatechin is increasingly considered due to its cardioprotective effects. The aim of this study was to investigate the impact of epicatechin on microparticle generation, phenotype and procoagulant properties. Plasma samples from 15 healthy subjects were incubated with increasing concentrations of epicatechin (1 to 100 μM). Then, the expression of glycoprotein IIb, phosphatidylserine (PS), glycoprotein Ib (GPIb) and P-selectin was assessed by flow cytometry analysis after (or not) platelet stimulation. Microparticle procoagulant activity was determined using Zymuphen^TM MP and Zymuphen^TM MP-TF for phospholipid and tissue factor content, and with thrombin generation (TG) assays for procoagulant function. Platelet microparticles that express GPIb (/µL) decreased from 20,743 ± 24,985 (vehicle) to 14,939 ± 14,333 (p = 0.6), 21,366 ± 16,949 (p = 0.9) and 15,425 ± 9953 (p < 0.05) in samples incubated with 1, 10 and 100 µM epicatechin, respectively. Microparticle concentration (nM PS) decreased from 5.6 ± 2.0 (vehicle) to 5.1 ± 2.2 (p = 0.5), 4.5 ± 1.5 (p < 0.05) and 4.7 ± 2.0 (p < 0.05) in samples incubated with 1, 10 and 100µM epicatechin, respectively. Epicatechin had no impact on tissue factor-positive microparticle concentration. Epicatechin decreased TG (endogenous thrombin potential, nM.min) from 586 ± 302 to 509 ± 226 (p = 0.3), 512 ± 270 (p = 0.3) and 445 ± 283 (p < 0.05). These findings indicate that epicatechin affects microparticle release, phenotype and procoagulant properties.

Advances in physiological functions and mechanisms of (-)-epicatechin

(-)-Epicatechin (EC) is a flavanol easily obtained through the diet and is present in tea, cocoa, vegetables, fruits, and cereals. Recent studies have shown that EC protects human health and exhibits prominent anti-oxidant and anti-inflammatory activities, enhances muscle performance, improves symptoms of cardiovascular and cerebrovascular diseases, prevents diabetes, and protects the nervous system. With the development of modern medical and biotechnology research, the mechanisms of action associated with EC toward various chronic diseases are becoming more apparent, and the pharmacological development and utilization of EC has been increasingly clarified. Currently, there is no comprehensive systematic introduction to the effects of EC and its mechanisms of action. This review presents the latest research progress and the role of EC in the prevention and treatment of various chronic diseases and its protective health effects and provides a theoretical basis for future research on EC.

Phenolic Profiles of Leaves, Grapes and Wine of Grapevine Variety Vranac (Vitis vinifera L.) from Montenegro

Vranac, an old autochthonous red grapevine variety of Montenegro, was first mentioned in a historical document published in the 15th century. As currently the study of indigenous varieties is of particular importance, the subject of this work was detailed characterization of phenolic compounds in the autochthonous grapevine variety Vranac, from the Montenegrin Podgorica subregion. Phenolic profiles of leaves, berries (skin, seeds, and pulp were examined separately) and young monovarietal wine were determined using ultra-high performance liquid chromatography (UHPLC) with linear trap quadrupole (LTQ)—Orbitrap XL mass spectrometry (MS). Total phenolic content (TPC) and radical scavenging activity (RSA) were higher for the grape seeds extracts, followed by extracts of grape skins and pulps. As expected, the total anthocyanin content (TAC) was higher in grape skin than in wine. A total of one hundred twenty nine compounds (forty two phenolic acids and their derivatives, twenty three flavan-3-ols, twenty one flavanols, five stilbenes and thirty eight anthocyanins) were identified in the investigated extracts. To our best knowledge, this is the first report of tentative identification of (epi)catechin 3-O-coumarate in grape seed and chalcan-flavan 3-ol dimers in wine and grape seed.

Optimizing Nucleophilic Depolymerization of Proanthocyanidins in Grape Seeds to Dimeric Proanthocyanidin B1 or B2

Depolymerization of polymeric proanthocyanidins (PPCs) in grape seeds into oligomeric proanthocyanidins (OPCs), especially the dimers, has important academic significance and practical value. Reaction conditions including nucleophilic reagent/PPC mass ratio, HCl concentration, reaction time, and temperature were systematically optimized by central composite design to maximize the yield of the dimeric product B2 or B1. The yield of B2 reached 3.35 mg mL^-1 under the conditions of (-)-epicatechin/PPC mass ratio 2.8, HCl concentration 0.06 mol, reaction time 16 min and temperature 36 °C, and that of B1 reached 3.64 mg mL^-1 under the conditions of (+)-catechin/PPC mass ratio 2.8, HCl concentration 0.07 mol, reaction time 17 min, and temperature 34 °C. Overall, this study has provided theoretical guidance and a practical approach to improvethe reaction process and economic value of proanthocyanidins in grape seed proanthocyanidin extract.

Relative abundances of novel cyclic prodelphinidins in wine depending on the grape variety

The identification of cyclic B-type procyanidins in grape and wine was recently disclosed. Some of these were also found in berries of totally different vegetal species (eg, Vaccinium sp.). However, presence of a wider class of these cyclic condensed tannin compounds with variably substituted monomers has never been addressed so far. Here, an extended list of oligomeric cyclic proanthocyanidins (PAC) bearing variable substitution patterns on the main flavan-3-ol unit has been searched in wines. Nearly 7600 theoretical structures were calculated and searched in red and white wine samples made from different grape varieties. Moreover, a hydrogen/deuterium exchange approach (already applied to a cyclic tetrameric procyanidin) coupled to high-resolution mass spectrometry was applied to confirm their cyclic B-type structure rather than a non cyclic A-type structure, otherwise isomeric and undistinguishable by LC-MS alone. The main group of novel cyclic PAC observed is shown to contain (epi)gallocatechin beside (epi)catechin as the constituent monomers.