Holistic understanding of the response of grapevines to foliar application of seaweed extracts.

Viticulture is highly dependent on phytochemicals to maintain good vineyard health. However, to reduce their accumulation in the environment, green regulations are driving the development of eco-friendly strategies. In this respect, seaweeds have proven to be one of the marine resources with the highest potential as plant protective agents, representing an environmentally-friendly alternative approach for sustainable wine production. The current work follows an interdisciplinary framework to evaluate the capacity of Ulva ohnoi and Rugulopteryx okamurae seaweeds to induce defense mechanisms in grapevine plants. To our knowledge, this is the first study to evaluate Rugulopteryx okamurae as a biostimulator . This macroalgae is relevant since it is an invasive species on the Atlantic and Mediterranean coast causing incalculable economic and environmental burdens. Four extracts (UL1, UL2, RU1 and RU2 developed from Ulva and Rugulopteryx, respectively) were foliar applied to Tempranillo plants cultivated under greenhouse conditions. UL1 and RU2 stood out for their capacity to induce defense genes, such as a PR10, PAL, STS48 and GST1, mainly 24 hours after the first application. The increased expression level of these genes agreed with i) an increase in trans-piceid and trans-resveratrol content, mainly in the RU2 treated leaves, and, ii) an increase in jasmonic acid and decrease in salicylic acid. Moreover, an induction of the activity of the antioxidant enzymes was observed at the end of the experiment, with an increase in superoxide dismutase and catalase in the RU2-treated leaves in particular. Interestingly, while foliar fungal diversity was not influenced by the treatments, alga extract amendment modified fungal composition, RU2 application enriching the content of various groups known for their biocontrol activity. Overall, the results evidenced the capacity of Rugulopteryx okamurae for grapevine biostimulation, inducing the activation of several secondary metabolite pathways and promoting the abundance of beneficial microbiota involved in grapevine protection. While further studies are needed to unravel the bioactive compound(s) involved, including conducting field experiments etc., the current findings are the first steps towards the inclusion of Rugulopteryx okamurae in a circular scheme that would reduce its accumulation on the coast and benefit the viticulture sector at the same time.

Sulfur dioxide-free Verdejo wines through the use of a pure stilbene extract: exploring possible synergistic effect with glutathione.

BACKGROUND: The search for alternatives to sulfur dioxide (SO2 ) in white wine production is a tough challenge for the oenological industry. The current article investigates the effectiveness of several preservatives in protecting Verdejo white wines. The following wines were elaborated: without preservative (CT wines), with SO2 (SO2 wines), with stilbene-enriched extract (ST99 wines), with glutathione (GSH wines) and finally with the combination stilbene extract plus glutathione (ST99-GSH wines). RESULTS: ST99 extract preserved the wines from malolactic fermentation (MLF), maintained the quality parameters of the wines, but affected their color from the beginning of the process. Synergistic effects between ST99 and GSH were found for oxygen consumption rates, related to oxidation processes. The content of amino acids and biogenic amines was slightly affected by the treatments, but the quality or safety of the wines was not compromised. However, after 12 months of ageing in bottle, the SO2 wines showed the highest score in the sensory analysis. The reasons for the evolution of treated wines and the implications of this study for maintaining the quality of free SO2 white wines are discussed. CONCLUSION: ST99 may be proposed as an alternative to SO2 in wines to be consumed in the short term. Its combination with GSH does not prolong its shelf-life. © 2022 Society of Chemical Industry.

Cytotoxicity studies of a stilbene extract and its main components intended to be used as preservative in the wine industry.

The use of stilbenes has been proposed as an alternative to sulfur dioxide in wine. Provided the feasibility from a technological approach, the cytotoxicity of an extract from grapevine shoots containing a stilbene richness of 99% (ST-99 extract) was assessed in the human cell lines HepG2 and Caco-2. In addition, the effects of the main stilbenes found in ST-99, trans-resveratrol and trans-ε-viniferin were studied, as well as its mixture. Similar cytotoxic effects were obtained in the exposures to trans-ε-viniferin, ST-99 and the mixture; however, trans-resveratrol alone exerted less toxicity. When HepG2 cells were exposed to trans-ε-viniferin, ST-99 and the mixture, the mean effective concentration (EC50) were 28.28 ± 2.15, 31.91 ± 1.55 and 29.47 ± 3.54 µg/mL, respectively. However, in the exposure to trans-resveratrol, the EC50 was higher 50 µg/mL. The morphological study evidenced damage at ultrastructural level in HepG2 cells, highlighting the inhibition of cell proliferation and the induction of apoptosis. The type of interaction produced by trans-ε-viniferin and trans-resveratrol mixtures was assessed by an isobologram analysis using the CalcuSyn software, evidencing an antagonist effect. These data comprise a starting point in the toxicological assessment; further studies are needed in this field to assure the safety of the extract ST-99.

Grapevine Cane Extracts: Raw Plant Material, Extraction Methods, Quantification, and Applications.

Grapevine canes are viticulture waste that is usually discarded without any further use. However, recent studies have shown that they contain significant concentrations of health-promoting compounds, such as stilbenes, secondary metabolites of plants produced as a response to biotic and abiotic stress from fungal disease or dryness. Stilbenes have been associated with antioxidant, anti-inflammatory, and anti-microbial properties and they have been tested as potential treatments of cardiovascular and neurological diseases, and even cancer, with promising results. Stilbenes have been described in the different genus of the Vitaceae family, the Vitis genera being one of the most widely studied due to its important applications and economic impact around the world. This review presents an in-depth study of the composition and concentration of stilbenes in grapevine canes. The results show that the concentration of stilbenes in grapevine canes is highly influenced by the Vitis genus and cultivar aspects (growing conditions, ultraviolet radiation, fungal attack, etc.). Different methods for extracting stilbenes from grapevine canes have been reviewed, and the extraction conditions have also been studied, underlining the advantages and disadvantages of each technique. After the stilbenes were extracted, they were analyzed to determine the stilbene composition and concentration. Analytical techniques have been employed with this aim, in most cases using liquid chromatography, coupled with others such as mass spectrometry and/or nuclear magnetic resonance to achieve the individual quantification. Finally, stilbene extracts may be applied in multiple fields based on their properties. The five most relevant are preservative, antifungal, insecticide, and biostimulant applications. The current state-of-the-art of the above applications and their prospects are discussed.

Red Wine Extract Disrupts Th17 Lymphocyte Differentiation in a Colorectal Cancer Context.

SCOPE: Scope: It is well established that immune response and inflammation promote tumoral progression. Immune cells communicate through direct contact or through cytokine secretion, and it is the pro-inflammatory status that will tip the balance toward tumor progression or anti-tumor immunity. It is demonstrated here that a red wine extract (RWE) can decrease inflammation through its action on the inflammasome complex. This study determines whether an RWE could impact other key actors of inflammation, including T helper 17 (Th17) immune cells in particular. METHODS AND RESULTS: Methods and results: Using an RWE containing 4.16 g of polyphenols/liter of wine, it is shown that RWE decreases colorectal cancer cells in vitro and induces a reduction in colorectal tumor growth associated with a decrease in tumor-infiltrating lymphocytes in vivo. The process of T-lymphocyte differentiation in Th17 cells is altered by RWE, as revealed by the decrease in the expression of key actors controlling this process, such as signal transducer and activator of transcription 3 and retinoid acid-related orphan receptor γt. This disruption is associated with an inhibition of inflammatory interleukin 17 secretion. CONCLUSION: The data highlights the major involvement of Th17 immune cells in the biological effects of an RWE.

Inhibition of VEGFR-2 Phosphorylation and Effects on Downstream Signaling Pathways in Cultivated Human Endothelial Cells by Stilbenes from Vitis Spp.

Stilbenes are phenolic compounds present in different higher plant families that have shown different biological activities, such as antioxidant properties and antitumoral and anti-atherosclerotic effects, among others. Angiogenesis is a key process involved in both cancer and cardiovascular diseases, the vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 being the main triggers. Certain polyphenol compounds, such as flavonoids, have shown a potent capacity to inhibit VEGF and, consequently, angiogenesis. The present work, therefore, aims to evaluate the potential effect of stilbenes on inhibiting VEGF and their subsequent effect on the downstream signaling pathway (PLCγ1, Akt, and eNOS). VEGFR-2 activation was studied through an ELISA assay in the HUVEC line, while the phosphorylation of intracellular downstream proteins PLCγ1, Akt, and eNOS was tested by Western blot. Student's t test was used to determine significant differences between samples. On the one hand, astringin, pallidol, and ω-viniferin showed the lowest IC50 values (2.90 ± 0.27, 4.42 ± 0.67, and 6.10 ± 1.29 µM, respectively) against VEGFR-2 activation. Additionally, VEGF-induced PLCγ1 phosphorylation was significantly inhibited by ε-viniferin, astringin, and ω-viniferin. However, ε-viniferin and pallidol simultaneously enhanced eNOS activation, proving to be via Akt activation in the case of ε-viniferin. For the first time, these data suggest that stilbenes such as astringin, pallidol, ω-viniferin, and ε-viniferin have a potential anti-angiogenic effect and they could be further considered as anti-VEGF ingredients in food and beverages. In addition, ε-viniferin and pallidol significantly allowed eNOS activation and could likely prevent the side effects caused by anti-VEGF hypertension drugs.

Study of Potential Anti-Inflammatory Effects of Red Wine Extract and Resveratrol through a Modulation of Interleukin-1-Beta in Macrophages.

Inflammation has been described as an initiator event of major diseases with significant impacts in terms of public health including in cardiovascular disease, autoimmune disorders, eye diseases, age-related diseases, and the occurrence of cancers. A preventive action to reduce the key processes leading to inflammation could be an advantageous approach to reducing these associated pathologies. Many studies have reported the value of polyphenols such as resveratrol in counteracting pro-inflammatory cytokines. We have previously shown the potential of red wine extract (RWE) and the value of its qualitative and quantitative polyphenolic composition to prevent the carcinogenesis process. In this study, we addressed a new effect of RWE in inflammation through a modulation of IL-1ß secretion and the NLRP3 inflammasome pathway. NLRP3 inflammasome requires two signals, priming to increase the synthesis of NLRP3 and pro-IL-1ß proteins and activation, which activates NLRP3. Inflammasome formation is triggered by a range of substances such as lipopolysaccharide (LPS). Using two different macrophages, one of which does not express the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD), which is essential to form active inflammasome complexes that produce IL-1ß, we show that RWE decreases IL-1 ß secretion and gene expression whatever line is used. Moreover, this strong reduction of pro-inflammatory IL-1ß is associated with a decrease of NLRP3 and, in J774A, ASC protein expression, which depends on the choice of activator ATP or nigericin.

Stilbenes from Vitis vinifera L. Waste: A Sustainable Tool for Controlling Plasmopara Viticola.

Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-ε-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.

Daily Preharvest UV-C Light Maintains the High Stilbenoid Concentration in Grapes.

The fact that it is possible to induce stilbenoid synthesis in grapevine (Vitis vinifera) by UV-C light allows the possibility of stimulating grapevine phytoalexin production to increase disease resistance and immunity, and subsequently to limit the use of pesticides in vineyards. UV-C light was applied daily during three days before the harvesting of table grape variety Crimson seedless to study the accumulation of stilbenoid compounds during ripeness. The E-resveratrol concentration was monitored during daily preharvest UV-C light application and compared with that after a single application. Daily periodic preharvest UV-C light treatment showed a cumulative effect on grape stilbenoids. An 86-fold stilbenoid level increase (sum of E-resveratrol, E-piceatannol, ε-viniferin, E-piceid, isorhapontigenin, ω-viniferin, and Z-piceid) in grapes was achieved. The effects of UV-C light on stilbenoid in grape cane was also addressed for the first time. Stilbenoid oligomers such as hopeaphenol, ampelopsin A, and r-viniferin were quantified in cane samples. Quality grape parameters indicated an acceleration of ripening in UV-C samples.

Ultrasound-assisted extraction of stilbenoids from grape stems.

A new method for fast determination of stilbenoids from grape stems was developed. Ultrasound-assisted extraction was applied prior to chromatographic determination of stilbenoids in the extracts, and the stability of stilbenoids under extraction conditions was checked. A fractional experimental design was developed to analyze the influence on the extraction process of seven different extraction variables: temperature, ultrasound amplitude, ultrasonic cycle duration, ultrasonic probe type, time, sample-solvent ratio, and solvent (mixtures of ethanol and water). The most important variables for the recovery of major stilbenoids were studied and the final conditions optimized. With this new method, the main stilbenoids found in grape stems can be extracted in 15 min, using 75 °C as the extraction temperature and 80% ethanol as the extraction solvent, and no cleaning step with organic solvent is needed. The optimized method allowed for the analysis of stilbenoid content from 22 grape stem samples, many of them analyzed for the first time.

Isorhapontigenin: a novel bioactive stilbene from wine grapes.

Stilbenes are a family of bioactive compounds found in plants. However, only a few stilbenes are present in the human diet. Grape and wine are the main dietary source of stilbenes, resveratrol and piceid being the most common ones. Ultraviolet C light (UVC) postharvest treatment was used to obtain significantly increased stilbene concentration in grapes. A new, previously undescribed-in-grapes stilbene was found after UVC treatment. The process followed to isolate and identify this unknown stilbene is described in the present work. This isolation involved several fractionation steps including counter current chromatography and semi-preparative HPLC due to its low concentration and the presence of structurally related compounds. The structure of the compound was unequivocally identified by NMR spectroscopy analyses including (1)H-NMR; COSY; ROESY; HSQC and HMBC. The compound was identified as isorhapontigenin (ISOR), a stilbene found in traditional Asian medicinal plants. To the best of our knowledge this is the first report of its occurrence in grapes.

Wine, resveratrol and health: a review.

Several studies have cited the Mediterranean diet as an example of healthy eating. In fact, the Mediterranean diet has become the reference diet for the prevention of cardiovascular disease. Red wine seems to be an essential component of the diet, since moderate consumption of wine is associated with lower risk and mortality from cardiovascular disease. Evidence is also accumulating that wine helps prevent the development of certain cancers. Of all the many components of wine, resveratrol, which is a natural component specifically present in wine, has been identified as being mainly responsible for these health-promoting properties. Many valuable properties such as cardioprotective and anticarcinogenic activity have been attributed to resveratrol; however, its bioavailability is quite low. The bioactivity of metabolites derived from resveratrol, and the accumulation of resveratrol in vital organs are still under study, but there are high expectations of positive results. Other stilbene compounds are also considered in this review, despite being present in undetectable or very small quantities in wine. The present paper reviews all aspects of the health properties of wine, bioactive compounds found in wine, and their concentrations, bioavailability and possible synergistic effects.

Ingredients for functional drinks in neurodegenerative diseases: a review.

Several studies have indicated that oxidative stress is a major risk factor for the initiation and progression of neurological disorders like Parkinson's disease (PD) and Alzheimer's (AD). Therefore, reducing oxidative stress appears to be a rational choice for the prevention and reduction in the rate of progression of these neurological disorders. The brain utilizes about 25% of respired oxygen even though it represents only 5% of the body weight. Free radicals are generated during the normal intake of oxygen, during infection, and during normal oxidative metabolism of certain substrates. Although experimental data are consistent in demonstrating the neuroprotective effects of antioxidants in vitro and in animal models, the clinical evidence that antioxidant agents may prevent or slow the course of these diseases is still relatively unsatisfactory, and insufficient to strongly modify clinical practice. In this paper, natural possible substances that could be added to a beverage to prevent or decrease the developing of neurodegenerative diseases are reviewed.