Diethyl Succinate Modulates Microglial Polarization and Activation by Reducing Mitochondrial Fission and Cellular ROS

Succinate is a metabolite in the tricarboxylic acid cycle (TCA) which plays a central role in mitochondrial activity. Excess succinate is known to be transported out of the cytosol, where it activates a succinate receptor (SUCNR1) to enhance inflammation through macrophages in various contexts. In addition, the intracellular role of succinate beyond an intermediate metabolite and prior to its extracellular release is also important to the polarization of macrophages. However, the role of succinate in microglial cells has not been characterized. Lipopolysaccharide (LPS) stimulates the elevation of intracellular succinate levels. To reveal the function of intracellular succinate associated with LPS-stimulated inflammatory response in microglial cells, we assessed the levels of ROS, cytokine production and mitochondrial fission in the primary microglia pretreated with cell-permeable diethyl succinate mimicking increased intracellular succinate. Our results suggest that elevated intracellular succinate exerts a protective role in the primary microglia by preventing their conversion into the pro-inflammatory M1 phenotype induced by LPS. This protective effect is SUCNR1-independent and mediated by reduced mitochondrial fission and cellular ROS production.

“Portugizac Mlado vino”; is the aroma of younger red wine more attractive?

“Portugizac Mlado vino” is a local red wine with Protected designation of origin and Traditional term, and it is usually consumed very soon after alcoholic fermentation as a young wine. The maturation and aging of the wine affect the aroma composition, which is generally not pronounced and specific in the case of most red wines, but, as a sensory property, it is important for the perception of quality and consumer choice. The objective of this work was to analyze the most important aroma compounds of esters and higher alcohols, with the unpleasant volatile phenols too, in “Portugizac” wines, related to aging. The 9 young wines “Portugizac”, PDO “Plešivica” were analyzed after 3 and after 15 months of bottle storage at 16 ºC. Ethyl esters of butanoic and hexanoic acid along with isoamyl acetate are considered to be the most important esters in the fruity aroma of wine, and their concentrations in all analyzed “Portugizac” young wine samples were higher than their perception thresholds. The concentration of ethyl acetate was in the range 30-123 mg/L. The concentrations of ethyl esters of octanoic and decanoic acid, as well as 2-phenyl ethyl acetate and diethyl succinate in all analyzed wines, were lower than their perception thresholds. The concentrations of higher alcohols were much higher than their perception threshold. Bottle storage significantly affected the concentrations of analyzed compounds; after 15 months, the concentrations of acetate and ethyl esters (except ethyl acetate and diethyl succinate), as well as terpene (linalool), decreased, while higher alcohols and ethyl phenols slightly increased if compared to three months. In general, the compounds responsible for the desired fresh, fruity aroma tones were altered in an undesirable manner, while, undesirable compounds of 4-ethyl-phenol and 4-ethyl-quaiacol, which were not present in young wines, were detected in aged wines. It can be concluded that the bottle aging affects the aroma profile, undesirable changes were more pronounced than positive ones and therefore the consumption of young wine “Portugizac” might be more sensory attractive.

[2,5-Bis(dipropylamino)-4-(hydroxymethyl)phenyl]methanol

The centrosymmetric title compound, C22H36N2O2, was prepared in five steps from diethyl succinate. The dipropylamino groups are almost orthogonal to the central phenylenedimethanol ring [dihedral angle = 87.62 (9)°]. In the crystal, the molecules are connected by O—H...N hydrogen bonds, forming (101) layers separated by the propyl chains.

Impact of Different Stoppers on the Composition of Red and Rosé Lagrein, Schiava (Vernatsch) and Merlot Wines Stored in Bottle

Different technical cork stoppers (blend of natural cork microgranules, one-piece natural cork, agglomerated natural cork, technical cork 1+1) were compared to evaluate the effects on the phenolic, volatile profiles and dissolved oxygen in three red (Merlot, Lagrein red, St. Magdalener) and one rosé (Lagrein rosé) wines, which were stored in bottles for 12 months. Gallic acid, caffeic acid, p-coumaric acid, trans-resveratrol, glutahionyl caftaric acid and protocatechuic acid did not vary remarkably during the first three months, whereas at six months a net increase was reported, followed by a clear decrease at 12 months. The same trend was observed in Lagrein rosé, but only for gallic acid. The total anthocyanins content decreased during the storage period in the four wines. Isopentyl acetate, 1-hexanol, ethyl hexanoate, 2-phenylethyl alcohol, diethyl succinate, ethyl octanoate and ethyl decanoate were the main volatile compounds. The sum of alcohols decreased in all four of the wines. The esters decreased in Merlot; however, they increased in Lagrein rosé, Lagrein red and St. Magdalener during the storage. Univariate and multivariate statistics and a sensory discriminant triangle test displayed similar influences of the different stoppers on the phenolic and volatile compounds during the whole storage duration. The changes detected in the phenolic and volatile concentrations were presumably due to the non-oxygen-mediated reactions occurring during 12 months of storage in bottle.

Exploring the Typicality, Sensory Space, and Chemical Composition of Swedish Solaris Wines

The Swedish wine industry has exponentially grown in the last decade. However, Swedish wines remain largely unknown internationally. In this study, the typicality and sensory space of a set of twelve wines, including five Swedish Solaris wines, was evaluated blind by Swedish wine experts. The aim of the work was to evaluate whether the Swedish wine experts have a common concept of what a typical Solaris wines should smell and taste like or not and, also, to bring out more information about the sensory space and chemical composition of Solaris wines. The results showed a lack of agreement among the wine experts regarding the typicality of Solaris wines. This, together with the results from the sensory evaluation, could suggest the possibility of different wine styles for Solaris wines. From a chemical perspective, the global volatile profile showed a larger variability between individual wines than between Solaris and non-Solaris. However, 4MMP, ethyl propionate, ethyl 2-Methyl propanoate, and diethyl succinate were significantly higher in Solaris wines. Concerning non-volatile compounds, the results showed a significant discrimination between Solaris and non-Solaris wines, the former being characterized by higher ethanol %, Mg, succinic acid, tartaric acid, and sucrose levels.

The effect of wild Saccharomyces on composition and aroma of the Sauvignon blanc

ABSTRACTSaccharomyces strains isolated from vineyards in Southern Brazil were used as starter in micro-fermentations of Sauvignon Blanc juice (SB) to study the ability to produce different aromatic profiles. The molecular characterization allowed to differentiate the isolates from vineyards 06 CE, 11CE, 33CE, 01PP, 12M, 13PP, 26PP, 28AD, 41PP from the reference strain (2048SC) used in wine production. Under the same conditions tested, each strain belonging to the genus Saccharomyces produced metabolites in different concentration and combination, significantly influencing the aroma of the SB must. Volatile compounds such as octanoic acid, diethyl succinate and ethyl lactate were associated with the strains 26PP, 41PP, 01PP and 12M, while the strains 33CE, 28AD, 13PP and 06 CE were associated with the production of ethyl acetate, 1-hexanol, highlighting 06CE for production of 1-hexanol (592.87 ± 17.46 µg/L). In addition, the olfactory activity value (OAV> 1) allowed the evaluation of the range of participation of each compound in the final SB fermented. Finally, the selected wild strains are promising to improve the regional character of the wine.