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Pistacia lentiscus L. is a shrub of the Anacardiaceae family whose fruits are used in Tunisian and Algerian diets. The phenolic composition at 5 different physiological stages of the fruit was investigated using two different targeted methodologies: ultra-high-performance liquid chromatography–UV/visible detection (UHPLC-UV/vis) for anthocyanins and UHPLC coupled with tandem mass spectrometry (UHPLC-MS/MS) for the other polyphenols. For the specific analysis of anthocyanins, compound identification was confirmed by UHPLC-MS/MS and LC-NMR analysis. This study revealed the identification of 30 phenolic compounds including 9 anthocyanins, 7 flavanols, 7 flavonols, 2 phenolic acids, 1 stilbene, 2 flavanones, 1 flavanonol and 1 dihydrochalcone. Quantification showed significant qualitative and quantitative variation in phenolic content during the ripening of P. lentiscus fruits, flavonols being the main compounds for the unripe berries and anthocyanins for ripe berries. To the best of our knowledge, our study reports the presence of piceid and protocatechuic acid in P. lentiscus L. fruits, as well as several anthocyanins in Pistacia, for the first time. The results indicate potential applications of P. lentiscus L. fruits as a source of phenolic compounds to be used as nutraceuticals and as food colorants.

International audience; Aim: Stilbenes are well-known phytoalexins present in vine and wine. Stilbene glucosides have been identified in wine; however, other than piceid, these compounds have never been reported to be present in the woody parts of grapevine. The aims of this study were to investigate the presence of stilbene glucosides in the woody parts of the vine and to evaluate their cytotoxic activity, in comparison with that of resveratrol, in human hepatoma HepG2 cells. Methods and results: Stilbene glucosides were isolated from a Vitis vinifera root extract. The extract was partitioned with ethyl acetate and fractionated by polyamide gel column chromatography. Pure compounds were obtained by semipreparative high-performance liquid chromatography. These were then identified by mass spectrometry and nuclear magnetic resonance (NMR) analyses, including analysis of two-dimensional NMR spectra. In addition to resveratrol, five stilbene glucosides were found: resveratroloside, resveratrol rutinoside, trans-epsilon-viniferin diglucoside, cis-epsilon-viniferin diglucoside and piceid. Of these, the first four showed cytotoxic effects against HepG2 cells when the crystal violet assay was used to determine cell viability. Conclusion: In addition to resveratrol and piceid, this is the first report of the presence of four glucosylated derivatives of resveratrol (resveratroloside, resveratrol rutinoside, and trans- and cis-epsilon-viniferin diglucosides) in the woody parts of vine. These compounds showed significant cytotoxicity against HepG2 cells. Significance and impact of the study: Stilbenes are well-known biological compounds. Grapevine is one of the main sources of this family of polyphenols. Other than piceid, stilbene glucosides have been identified in wine but never in the woody parts of vine. This is the first study in which five glucosylated derivatives of resveratrol were isolated from woody parts of vine. They were also shown to exert antiproliferative effects in human hepatoma HepG2 cells.

Fraxinus angustifolia leaves and bark are used in traditional medicine against various inflammatory-related pathologies incumbent to reactive oxygen species (ROS) generation by the NADH oxidase activity of enzymes such as xanthine oxidoreductase (XOR). This study was designed to investigate the in vitro and in vivo inhibitory activities of this enzyme by Fraxinus angustifolia extracts. The leaf organic phase of ethyl acetate (LFA) and its bark aqueous counterpart (BFA) showed the strongest anti-NADH oxidase activity in vitro (IC50 = 38.51 and 42.04 μg mL-1, respectively). They consequently suppressed superoxide generation both enzymatically (53% and 19%, respectively) and nonenzymatically (34% and 19%, respectively). These results were corroborated in vivo, with high anti- NADH oxidase potential of the leaves and bark extracts (75.32% and 51.32%, respectively) concomitant with moderate hypouricemic activities (36.84% and 38.59%, respectively). Bio-guided fractionation led to the identification, by LC-DAD-MS/MS, of esculin and calcelarioside in bark and kaempferol glucoside in leaves as the main compounds responsible for the anti-NADH oxidase activity of XOR. These results plead in favor of the use of F. angustifolia as a source of potentially interesting therapeutic substances.

BACKGROUND Viticultural residues from commercial viticultural activities represent a potentially important source of bioactive stilbenes such as resveratrol. The main aim of the present study was therefore to isolate, identify and perform biological assays against amyloid-β peptide aggregation of original stilbenes from Vitis vinifera shoots. RESULTS A new resveratrol oligomer, (Z)-cis-miyabenol C (3), was isolated from Vitis vinifera grapevine shoots together with two newly reported oligostilbenes from Vitis vinifera shoots, vitisinol C (1) and (E)-cis-miyabenol C (2), and six known compounds: piceatannol, resveratrol, (E)-e-viniferin (trans-e-viniferin), ω-viniferin, vitisinol C and (E)-miyabenol C. The structures of these resveratrol derivatives were established on the basis of detailed spectroscopic analysis including nuclear magnetic resonance experiments. All the newly reported compounds were tested for their anti-aggregative activity against amyloid-β fibril formation. Vitisinol C was found to exert a significant activity against amyloid-β aggregation. CONCLUSION Vitis vinifera grapevine shoots are potentially interesting as a source of new bioactive stilbenes, such as vitisinol C. © 2013 Society of Chemical Industry

International audience; Three unusual dioxatricyclodecenone compounds, mollugoside A, E-mollugoside B and Z-mollugoside B and, together with known flavonoids, were isolated from the aerial parts of Galium mollugo collected in north-eastern Algeria. Their structures were elucidated by analysis of spectroscopic data, including 1D and 2D NMR. Flavonoids and mollugoside A significantly reduced reactive oxygen species (ROS) generation in human fibroblasts.

There are numerous studies indicating that a moderate consumption of red wine provides certain health benefits, such as the protection against neurodegenerative diseases. This protective effect is most likely due to the presence of phenolic compounds in wine. Wine polyphenolic compounds are well known for the antioxidant properties. Oxidative stress is involved in many forms of cellular and molecular deterioration. This damage can lead to cell death and various neurodegenerative disorders, such as Parkinson’s or Alzheimer’s diseases. Extensive investigations have been undertaken to determine the neuroprotective effects of wine-related polyphenols. In this review we present the neuroprotective abilities of the major classes of wine-related polyphenols.

Flavonoids are a large group of ubiquitous molecules synthesized by plants. Recent research has revealed that these molecules possess antioxidant activities which prevent free-radical damage to biological molecules like lipids, proteins and DNA, damage which can cause many cardiovascular and neurodegenerative diseases as well as cancer and diabetes. The underlying mechanisms involve metal chelation, free-radical scavenger capacities and inhibition of freeradical producing enzymes. Structure-activity studies have demonstrated common features of flavonoids that are highly important to their different activities. They include their planar structure; the number and position of their hydroxyl groups as well as the presence of the C2-C3 double bond. Many research groups indicated that flavonoids have shown cardioprotective activity, mainly through inhibition of lipid peroxidation. More recently, flavonoids are proven to be effective as anti-cancer agents, through apoptosis by induction of cell cycle arrest and inhibition of key enzymes involved in tumor promotion. Although discrepancies between in vitro and in vivo studies have been found, the elucidation of the mechanisms involved in flavonoid action will have many health benefits to man.

Extracts from the bark of Fraxinus angustifolia as well as the leaves of Pistacia lentiscus and Clematis flammula have been investigated for their reducing power, inhibition of linoleic acid peroxidation and scavenging capacity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and H 2 O 2 using in vitro spectrophotometric methods. The results indicate that the best overall antioxidant capacity was shown by extracts of Pistacia lentiscus , followed by Fraxinus angustifolia and Clematis flammula . Pistacia lentiscus aqueous fraction obtained from chloroform partition showed a high and dose-dependant reducing power (IC50 = 50.03 μg/ml), a very high scavenging ability against DPPH radical (IC50 = 4.24 μg/ml) and an outstanding activity against linoleic acid peroxidation (IC50 = 0.82 μg/ml). Fraxinus angustifolia aqueous fraction issued from chloroform extraction also exhibited a high DPPH scavenging activity (IC50 = 10.0 μg/ml) and a high activity against linoleic acid peroxidation (IC50=5.06 μg/ml). In contrast, it is the organic (chloroform) fraction of Clematis flammula that showed a high activity against linoleic acid peroxidation (IC50 4.6 μg/ml), whereas the aqueous fraction of chloroform partition showed a moderate scavenging activity against DPPH (IC50 = 25.02 μg/ml). The IC50 values for the antioxidant of reference, butylated hydroxyanisole (BHA) are 5.19, 6.16 and 71.16 μg/ml for inhibition of linoleic acid peroxidation, DPPH scavenging activity and reducing power, respectively. With the exception of Pistacia lentiscus aqueous extracts obtained from hexane and chloroform partitions that showed high H 2 O 2 scavenging ability, all the extracts from Fraxinus angustifolia and Clematis flammula showed only moderate and even weak capacity, respectively. The observed results which correlate positively with total phenol content strongly plead in favour of the use of these plants as potential food additives in replacement of synthetic compounds.

The flavonol profiles of grape berry skins were analysed in order to assess phenotypic variation between six grapevines belonging to six different species: Vitis vinifera, Vitis candicans, Vitis champinii, Vitis amurensis, Vitis cinerea and Vitis doaniana. High-performance liquid chromatography coupled to mass spectrometry (LC–MS) and NMR spectrometry (LC-NMR) were used to separate and identify the flavonols present in these species. The combination of LC–MS and LC–NMR data resulted in the identification of eighteen flavonols. In particular, the new flavonol diglycoside and pentoside derivatives were determined. In addition, the antioxidant capacities of flavonol grape skin extracts were evaluated by using an oxygen radical absorbance capacity method (ORAC).