Monitoring trans-Resveratrol in Grape Berry Skins During Ripening and in Corresponding Wines by HPLC

Natural Products: A Dependable Source of Therapeutic Alternatives for Inflammatory Bowel Disease through Regulation of Tight Junctions

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), can affect the entire gastrointestinal tract and mucosal layer and lead to intestinal damage and intestinal dysfunction. IBD is an inflammatory disease of the gastrointestinal tract that significantly impacts public health development. Monoclonal antibodies and other synthetic medications are currently used to treat IBD, but they are suspected of producing serious side effects and causing a number of other problems with long-term use. Numerous in vitro and in vivo studies have shown that organic macromolecules from plants and animals have an alleviating effect on IBD-related problems, and many of them are also capable of altering enzymatic function, reducing oxidative stress, and inhibiting the production of cytokines and release of proinflammatory transcriptional factors. Thus, in this paper, the natural products with potential anti-IBD activities and their mechanism of action were reviewed, with a focus on the protective effects of natural products on intestinal barrier integrity and the regulation of tight junction protein expression and remodeling. In conclusion, the insights provided in the present review will be useful for further exploration and development of natural products for the treatment of IBD.

Study of the impact of vine cultivation technology on the Feteasca Neagra wine phenolic composition and antioxidant properties

In this work a comparative assessment was performed on individual and total polyphenols and biochemical properties of some Feteasca Neagra red wines obtained from grapes cultivated with different farming technologies (organic vs. conventional). The effect of a 30% cluster thinning treatment in both organic and conventional vineyard, compared to control plots with no thinning, was also monitored. The wines were obtained during two vintages, one with more favourable climatic conditions and one less favourable, in the period 2010-2019. Our results indicate that by applying a 30% cluster thinning treatment in the vineyard it is possible to increase the concentration of total and individual polyphenols of the resulted Feteasca Neagra wines. Furthermore, the differences observed between the phenolic profiles of wines from conventionally and organically produced grapes showed that organic Feteasca Neagra wines have higher phenolic compounds concentrations and antioxidant properties, with some important individual phenols accumulating in larger quantities than in the case of conventional wines. The beneficial effect of the organic cultivation is more evident in years characterised by less favourable climatic conditions. The statistical analysis tools applied to the analytical data allowed a good discrimination of experimental wine variants according to the vine cultivation technology (organic vs. conventional, with and without cluster thinning) and vintage. Thus, the results indicated that the applied cultivation technologies, especially when both organic cultivation and cluster thinning are combined, can greatly improve the polyphenolic content of Feteasca Neagra wines. The absolute value of the increase in polyphenol concentration was higher in favourable years, but the relative increase, in percentages, as compared to control wines, was higher in less favourable years. The combination of both viticultural practices may be thus exploited in order to obtain wines with higher polyphenolic content, which leads to better structure, better ageing potential, enhanced nutritional and antioxidant properties.

Simultaneous Determination of Fifteen Polyphenols in Fruit Juice Using Ultrahigh-Performance Liquid Chromatography-Tandem Mass Spectrometry Combining Dispersive Liquid-Liquid Microextraction

Polyphenols are secondary metabolites of plants and used as effective antioxidants in dietary supplements, whose main sources are fruits, vegetables, and grains. To clarify the content and distribution of polyphenols in different fruit species samples accurately, a rapid and sensitive ultrahigh-pressure liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method combining dispersive liquid-liquid microextraction (DLLME) was developed for quantitative determination of fifteen polyphenol compounds in fruit juice. In this method, the targets were first extracted from 1 g of fruit juice sample using 10 mL of 80% ethanol solution by ultrasonic-assisted extraction (UAE). Then, 1.0 mL of UAE extracted solution, 60 μL of n-octanol and 2.0 mL of H₂O were performed in the following DLLME procedure. A C₁₈ reversed-phase column, ZORBAX SB (100 × 4.6 mm, 3.5 μm), was proposed under gradient elution with 0.1% formic acid aqueous solution and methanol mobile phases for the determination of 15 polyphenols, allowing us to obtain polyphenolic profiles in less than 23.0 min. Under the optimum conditions, the enrichment factors ranged from 162 to 194. The results showed that the 15 polyphenols had linear correlation coefficients (R²) more than 0.99. The limits of detection (LODs) were between 18.3 and 103.5 ng/g, and the average recoveries were between 96.9 and 116.3% with interday relative standard deviations (RSDs) ranging from 4.4 to 8.2% in all cases. The method was successfully applied to the analysis of real fruit juice samples and presented itself as a simple, rapid, practical, and environment-friendly technique.

Different approaches to enhance resveratrol content in wine

Resveratrol is a polyphenol with antioxidant properties and possible beneficial effects on human health. Grapes, peanuts, berries, cacao beans and red wine contain resveratrol. Resveratrol attracts attention due to its bioactive properties, however, the concentration of this compound is not high in grape and wine. Therefore, different studies have been carried out to increase resveratrol level in these products. Several factors such as the grapevine variety, the climatic conditions and the viticultural practices used to create stress on the vine affect the level of resveratrol. Winemaking technologies applied during pre-fermentation, fermentation and post–fermentation stages could also have an effect on the concentration of this stilbene. In addition, recent studies have evaluated biotechnological approaches through the use of different bacteria and yeast strains to produce wine with increased resveratrol content. In this review, the most important factors contributing to increase the resveratrol concentration in grapes and wines are examined. Besides, analytical methods to determine resveratrol content in wine are addressed.

α-Glucosidase Inhibitory Activity of Tannat Grape Phenolic Extracts in Relation to Their Ripening Stages

The present study aimed to screen grape extracts as novel α-glucosidase inhibitors to prevent type-2 diabetes and hyperglycemia. The total polyphenol content (TPC) was measured by Folin-Ciocalteu assay and the stilbene, anthocyanin and flavan-3-ol compounds were measured by Ultra High-Performance Liquid Chromatography coupled to Mass Spectrometry (UHPLC-MS). The α-glucosidase inhibitory of seed and skin Tannat grape extracts at four ripening stages were investigated. The highest TPC values were measured in seeds at the “veraison stage” (65.29 ± 5.33 g of Gallic Acid Equivalent (GAE) per kilogram of Fresh Weight (FW)). This was in accordance with the high flavan-3-ol contents measured for these two extracts (43.22 ± 2.59 and 45.45 ± 6.48 g/kg of seeds FW, respectively). The skin and seed extracts at the first stage of ripening exerted strong α-glucosidase inhibition, exceeding 95% (p < 0.05). A high linear correlation (R = 0.723, p ≤ 0.05) was observed between flavan-3-ol contents and the α-glucosidase inhibitory activity. The stilbene contents and this activity were moderately to strongly anti-correlated (R = –0.828, p ≤ 0.05 for trans-resveratrol). The enzyme kinetic studies revealed a mixed type of inhibition. This study brings promising results for the therapeutic potential of seed and skin Tannat grape extracts as a functional food product with anti-diabetic activity.

Evaluation of the quality of local butters: A new approach based on Raman spectroscopy and supported by the classical pycnometer method

In this study, the quality of the local Romanian butters was investigated using the classical pycnometer and optic microscopy methods, combined with Raman spectroscopy. We used a pool of 10 samples with different characteristics, and analyzed them by the three aforementioned methods. Pycnometric measurements showed a direct correlation between the fat content and the density values of the samples. Raman spectroscopy validated the results from the pycnometric measurements and the optical microscopy and indicated several other properties, such as protein content, hydration, saturation level of the polycarbonate chains, as well as the total cis isomer content and the type of arrangement preferred by the aliphatic chains (polymorphic transition). The methods employed in the present study have a strong potential to become analytical tools for the food industry and food safety agencies in order to assess the quality of butters and margarines, in a fast and cost-effective manner.

Polyphenolic Compounds, Antioxidant, and Cardioprotective Effects of Pomace Extracts from Fetească Neagră Cultivar

Grape pomace is a potential source of natural antioxidant agents. Phenolic compounds and antioxidant and cardioprotective properties of fresh and fermented pomace extracts obtained from Vitis vinifera L. red variety Fetească neagră grown in Romania in 2015 were investigated. Grape pomace extracts total phenolic index, total tannins, total anthocyanins, proanthocyanidins, flavan-3-ol monomers, stilbenes, and DPPH free radical scavenger were measured. The effect of a seven-day pretreatment with grape pomace extracts on the isoprenaline-induced infarct-like lesion in rats was assessed by ECG monitoring, serum levels of creatine kinase, aspartate transaminase, and alanine transaminase. Total serum oxidative status, total antioxidant response, oxidative stress index, malondialdehyde, total thiols, and nitric oxide have been also assessed. Higher phenolic content and antioxidant activity were found in fermented pomace extracts when compared to fresh pomace extracts. Pretreatment with grape pomace extracts significantly improved cardiac and oxidative stress parameters. In conclusion, Fetească neagră pomace extracts had a good in vitro antioxidant activity due to an important phenolic content. In vivo, the extracts had cardioprotective effects against isoprenaline-induced infarct-like lesion by reducing oxidative stress, fresh pomace extracts having a better effect.

Evaluation of Resveratrol in Cancer Patients and Experimental Models

Cancer is one of the top three causes of death in the United States. The treatment regimen for controlling cancer includes a number of approaches depending on the classification of the tumor. Treatment may include radiation, surgery, and cancer chemotherapy agents as well as other interventions. Natural products have been identified for centuries to contain active pharmacologic activity and have been a starting point for numerous drugs which are currently on the market. Resveratrol (RES) is a natural product generated in plants in response to environmental stress and growing conditions. RES has been recognized since 1997 to possess anticancer activity. This review discusses the dietary sources of RES and the relative amounts present in the various food sources. A few limited clinical studies have explored RES effects in patients with prostate and colorectal cancer and have suggested some beneficial results. Future studies need to expand the sample size for clinical examination of RES in order to provide a better profile for the potential benefit of RES in cancer patients. This review also describes the potential mechanisms of RES as an antioxidant and in alteration of cell signaling. Another aspect for the role of RES in cancer may be in the interaction with cancer chemotherapy agents. Cisplatin is a cancer chemotherapy agent used for the treatment of bladder, testicular, ovarian, and many other cancers. Cisplatin usage is associated with a high risk of nephrotoxicity. Experimental studies suggest that RES may reduce cisplatin renal toxicity. The proposed mechanisms of protection are reviewed.