Effects Of Grape Pomace Extract Research Articles

Characterization of Poly(vinyl alcohol)/gelatin films made with winery solid by-product (vinasse) extract

The aim of this study is to examine the effect of grape pomace extract (GP) on the technological, functional and structural properties of Poly (vinyl alcohol) (PVA)/fish gelatin (FG) blend films. The addition of different ratios of GP (0 %, 0.5 %, 1 %, 1.5 % and 2 %) to PVA/FG edible films improved their rheological properties. The complex viscosity value increased exponentially when 2 % GP was added to the composite films compared to samples without any added GP. FTIR results showed that PVA and FG were able to interact with GP. The surface morphology indicated that addition of GP enhanced the intermolecular polymer interactions of the PVA-FG-GP combination. Atomic force microscopy (AFM) revealed that the films with GP had homogenous and smoother surfaces. X-ray diffraction (XRD) results confirmed that the FG and PVA chains interacted with GP, causing structural repositioning. Further confirmation of the effective interaction between PVA, FG and GP came from the decrease in crystallinity as the concentration of GP was increased. The melting temperature (Tm) was enhanced with the addition of GP. The combination of GP with PVA/FG films improved the plasticizer and surfactant properties thereby enhancing the flexibility of the films. The water solubility parameter was improved with the addition of GP without compromising the barrier properties. The antioxidant activity of the films increased significantly with the addition of GP. A GP-enriched PVA/FG film can be used as an edible film for food packaging purposes.

Evaluation of physicochemical properties of dried Damavand’s apple slices under the effect of grape pomace extract

Evaluation of physicochemical properties of dried Damavand’s apple slices under the effect of grape pomace extract

Paradoxical Effect of Grape Pomace Extract on Cisplatin-Induced Acute Kidney Injury in Rats.

Cisplatin is one of the most used drugs in the therapy of different types of cancer. However, its use is limited by nephrotoxicity. This study investigated the effects of a commercially available grape pomace extract (GE) from Vitis vinifera on cisplatin-induced kidney toxicity in rats. Sixty-four male Wistar albino rats were randomly divided into eight groups. Groups 1–3 were controls, receiving 0.9% saline and doses 1 and 2 of GE respectively. Cisplatin was given to groups 4–8. Two groups received pretreatment with GE, while another two groups received pre- and post-treatment with GE. Blood samples were collected and all animals sacrificed. Kidneys were harvested for histopathological analysis. GE significantly increased blood creatinine and urea levels, the severity of kidney histopathological damage, and mortality in all cisplatin groups, except for group 7 which received pre- and post-treatment with a low dose of GE. Renal toxicity was determined by mortality and severe histopathological renal lesions. Additionally, the serum total antioxidant capacity (TAC) was not significantly modified in the treated groups compared to the control. These results indicate that the GE did not have a protective effect on cisplatin-induced nephrotoxicity; on the contrary, GE accentuated the toxic effect of cisplatin.

Effect of Grape Pomace Polyphenols With or Without Pectin on TMAO Serum Levels Assessed by LC/MS-Based Assay: A Preliminary Clinical Study on Overweight/Obese Subjects.

Growing evidence suggests that trimethylamine N-oxide (TMAO) is recognized as a biomarker of increased cardiovascular risk. So far, the evaluation of TMAO serum levels in the clinical practice is limited due to the lack of developing new facile methods with reduced limitations. However, few approaches were achieved to determine TMAO in serum by using mass spectrometry-based technique, some limitations were reported including the use of internal standards. Therefore, in this work, a liquid chromatography-mass spectrometry (LC/MS) based-assay was developed to evaluate the effect of grape pomace extract (Taurisolo®, group A) or Taurisolo®+pectin (group B) on TMAO serum levels in a cohort of overweight/obese subjects. The serum levels of TMAO have been assessed before and after treatment, through LC/MS analysis. After 8-week treatment, in both intervention groups TMAO serum levels significantly decreased (-78.58% p = 0.006 and -76.76% p = 0.001, group A and group B, respectively). Moreover, we performed several analyses aimed to validate the LC/MS method we used. The method has high precision (% C.V = from 12.12 to 3.92% and from 8.25 to 1.07% for intraday and interday, respectively) and accuracy (% bias = from -5.52 to 0.5% and from -1.42 to 3.08% for intraday and interday, respectively). TMAO recoveries from serum ranged from 99 to 97%; LOD: 2 ng/ml and LOQ: 6 ng/ml. In conclusion, we demonstrated the efficacy of a novel nutraceutical formulation in reducing TMAO serum levels in high cardiovascular risk-subjects, and proposed a useful, versatile and rapid LC/MS method for identification and quantization of TMAO, without the use of marked/isotopic internal standards. It, thus, may represent a novel and practical method with applications in clinical practice and nutraceutical research.Clinical Trial Registration: This study is listed on the ISRCTN registry with ID ISRCTN10794277 (doi: 10.1186/ISRCTN10794277).

Chitosan nanocomposite films incorporating cellulose nanocrystals and grape pomace extracts

Chitosan nanocomposite films incorporating grape pomace extract (GPE), either Cabernet Franc (CF; a red variety) or Viognier (a white variety), and cellulose nanocrystal (CNC) were prepared using a solvent casting method. Mechanical properties, water vapour permeability, color and opacity, crystalline structure, thermal properties, total phenolic content, and antioxidant activity of the films were characterized. Incorporating CNC alone significantly (P < .05) increased tensile strength of the films and decreased their percent elongation at break and water vapour permeability. Grape pomace extract had an opposite effect on mechanical properties by decreasing tensile strength but increasing percent elongation at break. Film color was mainly influenced by the presence and type of GPE. Films containing CF extract exhibited the darkest appearance with increased reddish and bluish hues. Addition of CNC significantly increased film opacity and the alignment of chitosan chains, while the effect of GPE was not significant. Thermal analysis showed that chitosan and CNC were partially miscible and that the addition of CNC did not significantly change decomposition temperature of the films. Incorporation of GPE significantly (P < .05) increase total phenolic content and antioxidant activity. Films containing CF had higher DPPH• radical scavenging capacity than their counterparts with Viognier. Film incorporating both CNC and CF shows greater potential for food packaging application because of a combination of improved physical properties and high antioxidant activity.

P 191 - Grape pomace extract, rich in polyphenols, stimulate the emergence of brown-like cells in white adipose tissue in spontaneously hypertensive rats and in 3T3-L1 adipocytes

This study investigated the effect of grape pomace extract (GPE) on brown-like induction in epididymal white adipose tissue (eWAT) from spontaneously hypertensive rat (SHR) receiving a high-fat diet (HF) and in 3T3-L1 adipocytes. HF increased eWAT adiposity and diameter in Wistar Kyoto (WKY) but not in SHR, while GPE (300 mg/kg/day) supplementation reduced adipocyte diameter in WKY and attenuated adipose inflammation in both strain. In contrast, GPE increase protein levels involved in the “browning” such as PGC-1a, PPARγ and UCP-1 from SHR eWAT. In differentiated adipocytes from SHR eWAT, UCP-1 protein levels significantly decreased in cells pre-treated with SB203580 (p38 inhibitor) or U0126 (ERK inhibitor) but not in cells treated with GPE alone suggesting that GPE enhance UCP-1 in part via p38 and ERK. In 3T3-L1 adipocytes treated with palmitate the pretreatment with GPE (30 mM) enhances the activation of the downstream of β-adrenergic signaling cascade (PKA, AMPK, p38, ERK) in part involved in mitochondrial biogenesis (UCP-1, PPARγ and PGC-1α) and in fatty acid oxidation (ATGL). These effects were comparable when epicatechin or quercetin (1 µM), the main flavonoids found in GPE, was used. Overall, GPE could induce brown-like adipocytes in white adipocytes supporting the utilization of winemaking residues, rich in polyphenols, to treat obesity or related diseases.

Grape pomace extract exerts antioxidant effects through an increase in GCS levels and GST activity in muscle and endothelial cells.

In a previous study, we demonstrated that a grape pomace extract (GPE) exerted antioxidant activity in endothelial (EA.hy926) and muscle (C2C12) cells through an increase in glutathione (GSH) levels. In the present study, in order to elucidate the mechanisms responsible for the antioxidant activity of GPE, its effects on the expression of critical antioxidant enzymes, such as catalase (CAT), superoxide dismutase (SOD)1, heme oxygenase 1 (HO-1) and gamma-glutamylcysteine synthetase (GCS) were assessed in EA.hy926 and C2C12 cells. Moreover, the effects of GPE on CAT, SOD and glutathione S-transferase (GST) enzymatic activity were evaluated. For this purpose, the C2C12 and EA.hy926 cells were treated with GPE at low and non-cytotoxic concentrations (2.5 and 10 µg/ml for the C2C12 cells; 0.068 and 0.250 µg/ml for the EA.hy926 cells) for 3, 6, 12, 18 and 24 h. Following incubation, enzymatic expression and activity were assessed. The results revealed that treatment with GPE significantly increased GCS levels and GST activity in both the C2C12 and EA.hy926 cells. However, GPE significantly decreased CAT levels and activity, but only in the muscle cells, while it had no effect on CAT levels and activity in the endothelial cells. Moreover, treatment with GPE had no effect on HO-1 and SOD expression and activity in both cell lines. Therefore, the present results provide further evidence of the crucial role of GSH systems in the antioxidant effects exerted by GPE. Thus, GPE may prove to be effective for use as a food supplement for the treatment of oxidative stress-induced pathological conditions of the cardiovascular and skeletal muscle systems, particularly those associated with low GSH levels.

Effects of grape pomace extract on the quality and shelf life of silver carp (Hypophthalmicthys molitrix) fillets during chill storage

The effects of grape pomace extract (0, 2 and 4%) on quality and shelf life of silver carp ( Hypophthalmicthys molitrix ) fillets during chill storage (4°C) were investigated. The control and the treated fillets were analyzed periodically for microbiological (TVC and PTC), chemical (TVB-N), and sensory characteristics. The results showed that grape pomace-treated samples have lower TVB-N (24.2 and 21.2 mg N/100 g, respectively), TVC (7.33 and 7.09 log cfu/g, respectively) and PTC (7.26 and 7.03 log cfu/g, respectively) at the end of the storage period. The results revealed that the addition of grape pomace extract has a positive effect on the sensory quality of silver carp fillets by retaining proper quality characteristics for a longer time and extends their shelf life during chill storage.

Antioxidant Effects of Grape Pomace on the Quality of Silver Carp (Hypophthalmichthys molitrix) Fillets During Refrigerated Storage

This study aimed to determine the phenolic content and antioxidant effect of grape pomace extract on silver carp fillets during refrigerated storage. Total phenolic content of grape pomace extract was quantified by colorimetric methods. Silver carp samples were treated with 0, 2, and 4% of grape pomace extract (g extract/100 g flesh) and stored 15 days in a refrigerator (4°C). Changes in pH, peroxide value, thiobarbituric acid, and heme iron at 0, 3, 6, 9, 12, and 15 days of storage were investigated. Results showed that the values of pH, peroxide value, and thiobarbituric acid increased and iron levels decreased in all treatments during storage (p < 0.05). The phenolic contents were generally much more influenced by the quality parameters treated compared to the control. The addition of grape pomace extract delayed lipid oxidation in silver carp fillet considerably during refrigerated storage. These results suggested that grape pomace extract has the potential to be used as a natural antioxidant.