Grapevine-shoot Extract Research Articles

In vivo predictive dissolution of the lipophilic phytochemicals trans-resveratrol, coenzyme Q10 and quercetin

Biphasic dissolution consisting of an aqueous dissolution and an overlaying organic distribution compartment, is an innovative screening approach for the oral bioavailability of pharmacologically active compounds. As in vivo-relevant dissolution methods predicting the in vivo bioavailability of compounds from natural extracts are lacking, we sought to establish and validate an in vivo predictive in vitro biphasic dissolution method (BiPHa+) using human pharmacokinetic data from oral formulations of trans-resveratrol, coenzyme Q10 (CoQ10) and quercetin (including a grapevine-shoot extract, micellar formulations, a water-dispersible formulation with reduced recrystallization, an oily dispersion and phytosomes). The formulations were characterized using the BiPHa+ and compared to conventional monophasic dissolution methods. The comparison emphasized the advantages of the BiPHa+ in terms of powerful correlation. In case of resveratrol and CoQ10, only the combination of aqueous non-sink dissolution with an organic absorption sink enabled the differentiation of formulations and their in vivo-relevant characterization. In particular, the expected bioavailability of micellar formulations cannot be estimated solely based on their water solubility. Concerning the quercetin formulations biphasic dissolution was not essential, but advantageous. Based on the obtained results, the BiPHa + can be applied not only for characterization of different formulations but also to natural products with different physicochemical properties, such as water solubility and lipophilicity.

Grapevine Shoot Extract Rich in Trans-Resveratrol and Trans-ε-Viniferin: Evaluation of Their Potential Use for Cardiac Health.

A grapevine shoot extract (GSE) was obtained using ultrasound-assisted extraction and characterized. The main phenolic constituents were identified as stilbenoids. Among them, trans-resveratrol and trans-ε-viniferin stood out. The GSE was administered to an isoproterenol-induced myocardial injury animal model. The extract alleviated the associated symptoms of the administration of the drug, i.e., the plasma lipid profile was improved, while the disturbed plasma ion concentration, the cardiac dysfunction markers, the DNA laddering, and the necrosis of myocardial tissue were diminished. This effect could be related to the anti-oxidative potential of GSE associated with its antioxidant properties, the increased levels of endogenous antioxidants (glutathione and enzymatic antioxidants), and the diminished lipid peroxidative markers in the heart. The results also revealed angiotensin-converting enzyme (ACE)-inhibitory activity, which indicated the potential of GSE to deal with cardiovascular disease events. This work suggests that not only trans-resveratrol has a protective role in heart function but also GSE containing this biomolecule and derivatives. Therefore, GSE has the potential to be utilized in the creation of innovative functional ingredients.

Protection and reversion role of a pure stilbene extract from grapevine shoot and its major compounds against an induced oxidative stress

Sulfur dioxide is a controversial preservative used in winemaking. Given its potential toxicity, it is of great interest to find alternatives aimed at replacing or reducing sulfur dioxide. The objective was to assess the antioxidant effects of a grapevine-shoot extract with 99% of stilbenes (ST-99), its major compounds (trans-resveratrol and trans-ε-viniferin) and their mixture (1:3.9) by measuring reactive oxygen species (ROS) and glutathione (GSH) levels in vitro. Their ability to protect against or reverse the effects of H2O2 on cells were also studied. The results showed that ST-99, followed by trans-ε-viniferin and the mixture, were able to reduce ROS levels, increased GSH content and exhibited antioxidant ability against an induced oxidative stress. Trans-resveratrol significantly reduced ROS content only at the highest concentrations. ST-99 at non-cytotoxic concentrations is more effective than the other compounds, which might be attributed to increased levels of GSH. The results suggest a promising use of ST-99.

Stilbenes Can Impair Malolactic Fermentation with Strains ofOenococcus oeniandLactobacillus plantarum

Malolactic fermentation (MLF) is an important step in winemaking to improve wine quality by deacidification, increased microbial stability, and modified wine flavor. The phenolic composition of the wine influences the growth and metabolism of the lactic acid bacteria (LAB) used for MLF. Due to increased cultivation of fungus-resistant grape cultivars, the present study aimed to analyze the influence of stilbenes on MLF because stilbenes play an important role as phytoalexins in plants to counteract fungal pathogens. The analysis showed that the grapevine-shoot extract Vineatrol and the stilbenes e-viniferin, ampelopsin A, r2-viniferin, and r-viniferin, as well as mixtures of the five stilbenes, decelerated malic acid degradation. This can be partially attributed to a reduced number of viable cells. However, the direct impact of stilbenes on the malolactic enzyme must also play a role, as shown by the finding that the viability of LAB stabilized, while at the same time, malic acid degradation was reduced. These results show that wines made from stilbene-rich grapes, such as fungus-resistant cultivars, might have a higher risk for a sluggish or incomplete MLF.

Effect of a grapevine-shoot waste extract on red wine aromatic properties.

The use of a grapevine-shoot extract (VIN) is being studied as an alternative to sulfur dioxide (SO2 ). VIN stabilizes anthocyanins and preserves polyphenolic compounds, and thus improves chromatic wine properties. In this study, selected aroma compounds (esters, C13 -norisoprenoids, oxidation and vine-shoot-related compounds), sensory analysis and the olfactometric profile were determined in the wines treated with VIN at two concentrations. Treatment with VIN hardly modified the content of esters and oxidation-related compounds in the wines. However, the high β-damascenone and isoeugenol contents and the increase in astringency at tasting in VIN wines were noteworthy, as were some odorant zones. All these were established as VIN markers after the chemometric data analysis. These data revealed that only the lowest dose tested may be recommended as a suitable alternative to SO2 . Although some aromatic properties of these wines may change, these changes are not considered to affect the quality of the wines negatively. These results are useful for wineries, which face having to discover the aroma-related processes in the challenge of producing SO2 -free wines without detriment to their sensory properties. © 2018 Society of Chemical Industry.

Front cover: Effects of a Grapevine Shoot Extract Containing Resveratrol and Resveratrol Oligomers on Intestinal Adenoma Development in Mice: In Vitro and In Vivo Studies

Front cover: Effects of a Grapevine Shoot Extract Containing Resveratrol and Resveratrol Oligomers on Intestinal Adenoma Development in Mice: In Vitro and In Vivo Studies

Sulfur free red wines through the use of grapevine shoots: Impact on the wine quality

Following a preliminary study to determine the possibility of using a grapevine shoot extract (VIN) as a sustainable alternative to sulfur dioxide (SO2), in this study, the chromatic features, phenolic composition, and sensory analysis of wines treated with VIN at two concentrations were studied during storage in bottle for the first time. The highest differences were found in phenolic compounds after 12months of storage in bottle. The VIN wines had a low content of free anthocyanins and were high in vinyl-pyranoanthocyanins, and B-type vitisins. Consequently, they showed better chromatic characteristics. Moreover VIN, especially at high dose, preserved non-anthocyanin phenolic compounds better than SO2. However, at this high dose some organoleptic properties were affected. VIN, when used at a low dose, is able to preserve wine composition without loss of quality.

Comparative analysis of biotransformation of trans‐resveratrol in worms, flies, mice and humans

BackgroundTrans‐resveratrol (RES) has received considerable interest in biomedical research in the last decade for its attributed health benefits and as a putative “energy restriction mimetic”. However, findings are mainly derived from model organisms including worms, fruit flies, and mice and usually do no take into account that biotransformation of RES may be species‐specific. Knowledge on the biotransformation processes may also explain better the inconsistency of biological data collected on RES.AimTo study the metabolism of RES in the different species in a comparative mannerMethodCaenorhabditis elegans (wild‐type N2, variety Bristol), grown for 48 h on NGM agar containing 100 μM RES and heat‐killed bacteria as food, were washed, homogenized and extracted with methanol. Fruit flies (Drosophila melanogaster) of the line w1118 (Bloomington Drosophila Stock Center, #5905) were raised on standard cornmeal‐agar medium supplemented with RES (200 and 500 μM). Flies were kept at a density of 50 animals per vial for at least one week. Male C57BL/6N mice (n=6) were fed a RES supplemented diet for 14 days, killed and blood was collected (German Animal Ethics Committee; ref. no: 55.2‐1‐54‐2532‐22‐11). 6 male healthy men ingested a single dose of a RES containing grapevine shoot extract (0.5 mg RES/mg KG). Blood and urine samples were collected (German Clinical Trials Register as DRKS00004311, Universal Trial Number (WHO) UTN: U1111‐1133–4621). All samples were analyzed under standardised conditions with LC‐DAD‐QToF‐MS/MS. Metabolites were characterized using fragmentation pattern, accurate masses and in part by reference substances.ResultsRES was extensively metabolized in C. elegans as well as in mice, but the metabolite profiles were highly diverse. In C. elegans at least 9 different sugar conjugates with RES‐phosphoglucoside and RES‐3‐glucoside as the predominant metabolites were found. In mice, at least 8 sulfate and glucuronide conjugates of RES and dihydro‐RES, a metabolite formed by the gut microbiota, were detected with dihydro‐RES‐glucuronide and ‐disulfate as the major entities. Only 18% of RES was found as the parent compound in worms and <1% in mice. In Drosophila, essentially the same phosphoglucoside and 3‐O‐glucoside conjugates were found like in C. elegans although the extent of conjugation appeared much lower with the RES aglycone dominating the spectrum. In humans, RES‐3‐sulfate was the main metabolite in plasma 1 h after ingestion whereas in the urine 12–24 h after ingestion dihydro‐RES and lunularin conjugates predominated but with huge interindividual variation.ConclusionSignificant differences in the biotransformation of RES between the species were observed. In mice and humans the metabolism of RES by the gut microflora is of major importance whereas these processes do not seem to play a role in worms and flies. Mice and humans differ regarding the phase‐II metabolism with huge interindividual differences in humans. Little is known about the biological activities of the various RES metabolites identified which warrants further investigations.

OP16 - Investigations on the oral bioavailability of trans-resveratrol and trans-ε-viniferin from native and micellar Vineatrol®30 grapevine-shoot extract in healthy volunteers

Vineatrol ® 30 grapevine-shoot extract contains the stilbenes trans-resveratrol as well as considerable amounts of the resveratrol dimer trans-e-viniferin. Resveratrol is a potent antioxidant, anti-inflammatory, and chemopreventive agent in vitro and in vivo, and is thought to be cardio- and neuroprotective. The bioavailability of these stilbene compounds in humans is low (ca. 1-2%). The aim of our project was therefore to enhance the oral bioavailability and thus potentially the biological activity of trans-resveratrol and trans-e-viniferin from Vineatrol ® 30, and to assess its safety in humans. We performed a single-blind crossover trial with twelve healthy volunteers, with the two study arms separated by ≥1-week washout periods. All participants orally ingested in random order capsules with a single dose of 500 mg Vineatrol ® 30 as native powder or liquid micelles. Blood samples were collected before (0 h) and after (0.5, 1, 2, 4, 6, 8 and 24 h) Vineatrol ® 30 intake. Urine samples were collected before (0 h) and 1-6, 6-12 and 12-24 h after intervention. Liver and kidney function parameters were quantified in serum samples before as well as 4 and 24 h after intake of Vineatrol ® 30. Blood and urine samples are currently being analysed for total trans-resveratrol and trans-e-viniferin by HPLC and serum samples for the activity of liver enzymes and further safety parameters. The pharmacokinetics of native and micellar stilbenes as well as the tolerability and safety of the native and micellar formulations will be presented.

Topoisomerase II-Targeting Properties of a Grapevine-Shoot Extract and Resveratrol Oligomers

Grapevine-shoot extracts (GSE), containing trans-resveratrol and resveratrol oligomers, are commercially available as food supplements. Considering the topoisomerase-targeting properties of trans-resveratrol, the question of whether GSE affect these enzymes, thereby potentially causing DNA damage, was addressed. In a decatenation assay, GSE potently suppressed the catalytic activity of topoisomerase IIα (≥5 μg/mL). The resveratrol oligomers ε-viniferin, r2-viniferin, and hopeaphenol, isolated from GSE, were also identified as topoisomerase IIα inhibitors. In the in vivo complexes of enzyme to DNA (ICE) bioassay, neither GSE, r2-viniferin, nor hopeaphenol affected the level of enzyme-DNA intermediates in A431 cells, thus representing catalytic inhibitors rather than topoisomerase poisons. GSE caused moderate DNA strand breaks (≥25 μg/mL) in the comet assay. Taken together, GSE presumably acts as a catalytic inhibitor of topoisomerase II with r2-viniferin and hopeaphenol as potentially contributing constituents. However, the increase of FPG-sensitive sites points to an additional mechanism that may contribute to the DNA-damaging properties of GSE constituents.

Content of heavy metals in Slovak varietal wines

Following a preliminary study to determine the possibility of using a grapevine shoot extract (VIN) as a sustainable alternative to sulfur dioxide (SO2), in this study, the chromatic features, phenolic composition, and sensory analysis of wines treated with VIN at two concentrations were studied during storage in bottle for the first time. The highest differences were found in phenolic compounds after 12 months of storage in bottle. The VIN wines had a low content of free anthocyanins and were high in vinyl-pyranoanthocyanins, and B-type vitisins. Consequently, they showed better chromatic characteristics. Moreover VIN, especially at high dose, preserved non-anthocyanin phenolic compounds better than SO2. However, at this high dose some organoleptic properties were affected. VIN, when used at a low dose, is able to preserve wine composition without loss of quality.

Activity-Guided Isolation of Resveratrol Oligomers from a Grapevine-Shoot Extract Using Countercurrent Chromatography

An activity-guided isolation of bioactive stilbenes has been carried out with the grapevine-shoot extract Vineatrol 30. After hexane precipitation of the polymeric constituents, the stilbene mixture was separated on a preparative scale using low-speed rotary countercurrent chromatography (LSRCCC). The antiproliferative activity of the separated LSRCCC fractions was then screened in the human cancer cell line A-431, and trans-resveratrol, trans-ε-viniferin, r-2-viniferin, hopeaphenol, and miyabenol C were identified as active principles. In addition, a new class of stilbene derivatives, which exhibit a γ-lactam ring structure and exert a weak growth-inhibiting activity in A-431 cells, has been identified.

The growth of the canine glioblastoma cell line D‐GBM and the canine histiocytic sarcoma cell line DH82 is inhibited by the resveratrol oligomers hopeaphenol and r2‐viniferin

Vineatrol(®) 30 is a grapevine-shoot extract, which contains resveratrol as well as considerable amounts of so-called resveratrol oligomers such as hopeaphenol and r2-viniferin. In this study, we analysed whether the two above-mentioned resveratrol oligomers were able to inhibit the growth of the canine glioblastoma cell line D-GBM and the canine histiocytic sarcoma cell line DH82, compared their potency to inhibit tumour cell growth with that of resveratrol and determined whether the induction of apoptosis via caspase 9 and 3/7 activation underlies the tumour cell growth-inhibiting effect of hopeaphenol and r2-viniferin. Vineatrol(®) 30, resveratrol, hopeaphenol and r2-viniferin inhibited the growth of D-GBM and DH82 cells in a concentration-dependent manner, whereby hopeaphenol and r2-viniferin were more potent than resveratrol itself in inhibiting the growth of the canine tumour cell lines. Moreover, the anti-proliferative effect of both resveratrol oligomers in D-GBM cells is based on their capacity to induce caspase 9 and 3/7 activation.

The Grapevine-Shoot Extract Vineatrol30 Inhibits the Chemically Induced Malignant Transformation of BALB/c-3T3 Cells

Vineatrol®30 (developed and produced jointly by Breko GmbH [Bremen, Germany] and Actichem [Montauban, France]) is a grapevine-shoot extract that contains resveratrol as well as considerable amounts of resveratrol oligomers. In the present study it is shown that Vineatrol30 at a noncytotoxic concentration of 2.3 μg/mL significantly reduced the number of malignantly transformed foci induced by a sequential treatment of BALB/c-3T3 cells with 3-methylcholanthrene and 12-O-tetradecanoylphorbol 13-acetate in the so-called BALB/c-3T3 cell transformation assay. At a higher concentration Vineatrol30 drastically decreased the relative plating efficiency of the cells. Furthermore, the results suggest that the resveratrol oligomers present in Vineatrol30, independently from resveratrol itself, were indeed able to inhibit the formation of malignantly transformed BALB/c-3T3 foci.

Potent Antioxidative Activity of Vineatrol®30 Grapevine-shoot Extract

The health promoting effects of a grapevine-shoot extract named Vineatrol30, which contains resveratrol (Resv) as well as considerable amounts of Resv oligomers, have recently been investigated. In the present study, we analyzed the free radical scavenging capacity, the ability to inhibit lipid peroxidation, and the capacity to enhance the human glutathione peroxidase 1 (GPx) and the human superoxide dismutase 1 (SOD) gene promoter activities of Vineatrol30. Vineatrol30 was able to scavenge the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical cation and led to concentration-dependent inhibition of lipid peroxidation, Vineatrol30 not being superior to Resv alone in both cases. Vineatrol30 also enhanced the gene promoter activities of human GPx and SOD expressed in V79 cells, whereas this effect could not be demonstrated for Resv. In summary, the results presented in this study show that the Vineatrol30 grapevine-shoot extract is a free radical scavenger and potent antioxidant at non-cytotoxic concentrations.