The kinetics of oxygen and SO2 consumption by red wines. What do they tell about oxidation mechanisms and about changes in wine composition?

This work seeks to understand the kinetics of O2 and SO2 consumption of air-saturated red wine as a function of its chemical composition, and to describe the chemical changes suffered during the process in relation to the kinetics. Oxygen Consumption Rates (OCRs) are faster with higher copper and epigallocatechin contents and with higher absorbance at 620 nm and slower with higher levels of gallic acid and catechin terminal units in tannins. Acetaldehyde Reactive Polyphenols (ARPs) may be key elements determining OCRs. It is confirmed that SO2 is poorly consumed in the first saturation. Phenylalanine, methionine and maybe, cysteine, seem to be consumed instead. A low SO2 consumption is favoured by low levels of SO2, by a low availability of free SO2 caused by a high anthocyanin/tannin ratio, and by a polyphenolic profile poor in epigallocatechin and rich in catechin-rich tannins. Wines consuming SO2 efficiently consume more epigallocatechin, prodelphinidins and procyanidins

Cross-tolerance to abiotic stresses in halophytes: Application for phytoremediation of organic pollutants

International audienceHalopytes are plants able to tolerate high salt concentrations but no clear definition was retained for them. In literature, there are more studies that showed salt-enhanced tolerance to other abiotic stresses compared to investigations that found enhanced salt tolerance by other abiotic stresses in halophytes. The phenomenon by which a plant resistance to a stress induces resistance to another is referred to as cross-tolerance. In this work, we reviewed cross-tolerance in halophytes at the physiological, biochemical, and molecular levels. A special attention was accorded to the cross-tolerance between salinity and organic pollutants that could allow halophytes a higher potential of xenobiotic phytoremediation in comparison with glycophytes

Test Case Generation of Actor Systems

Testing is a vital part of the software development process. It is even more so in the context of concurrent languages, since due to undesired task interleavings and to unexpected behaviours of the underlying task scheduler, errors can go easily undetected. Test case generation (TCG) is the process of automatically generating test inputs for interesting coverage criteria, which are then applied to the system under test. This paper presents a TCG framework for actor systems, which consists of three main elements, which are the original contributions of this work: (1) a symbolic execution calculus, which allows symbolically executing the program (i.e., executing the program for unknown input data), (2) improved techniques to avoid performing redundant computations during symbolic execution, (3) new termination and coverage criteria, which ensure the termination of symbolic execution and guarantee that the test cases provide the desired degree of code coverage. Finally, our framework has been implemented and evaluated within the aPET system

Phenolic metabolites as compliance biomarker for polyphenol intake in a randomized controlled human intervention

Clinical trials are needed to confirm the association between polyphenol consumption and lower incidence of chronic diseases observed in epidemiological studies. However, a reliable evaluation of polyphenol intake is complicated. An 8-week randomized controlled trial (78 subjects) was performed using two isoenergetic diets differing only for polyphenol contents. Then, urinary phenolic metabolite profiles were analysed using gas-chromatography with mass detection. Phenolic metabolites detected in 24-h-urine were hydroxylated phenolic acids with C1-C3 side chain in the group consuming polyphenol-rich diet. The intake of polyphenol-rich foods increases the excretion of phenolic metabolites in urine providing a profile, which may serve as compliance biomarker of polyphenol-rich diet. © 2014 Elsevier Ltd

Analyse UPLC-MS/MS et activité antiproliférative de l’extrait brut hydroacétonique des feuilles de Zanthoxylum gilletii (De wild.) P.G. Waterman (Rutaceae)

International audienceL’analyse UPLC-MS/MS de l’extrait brut hydroacétonique des feuilles de Zanthoxylum gilletii a permis l’identification de composés phénoliques tels l’acide gallique et dérivés (9,40 mg EAG/g ms), l’acide protocatéchique (0,22 mg EAP/g ms), des flavonoïdes (6,34 mg EQ/g ms) et des acides hydroxycinnamiques (4,24 mg EAC/g ms). L’étude de la cytotoxicité a montré que cet extrait possède une activité antiproliférative sur les cellules cancéreuses C6, SNB 75, GLI7 et GLI4F11 (CI50 < 0,01 mg/ml)

Phenolic acid and flavonol water extracts of Delonix regia red flowers

International audienceTraditional healthy beverages in several African counties were home-made by water extraction of flowers of Delonix regia (Boj.) Raf. This tree belongs to the local biodiversity of plants used in the local medicine. It is also part of the traditional bioproducts marketed within African village communities. Scaling-up at pilot plant level, by mimicking this local recipe, lead to concentrated bioproducts containing various natural phenolic compounds, most of t hem have never been yet published. A three-steps process was used to prepare concentrated of water-extracted soluble phenolics. This process included: phenol extraction of dried plant by overnight diffusion in acidified water, clarification then concentration of the macerate, using membrane technology. Total phenol contents were determined as gallic acid equivalents using the Folin-Ciocalteu method. Total flavonoid contents, as delphinidin equivalents, were determined using the UV-vis colorimetric method. Comparison of concentration factors of both phenol families (phenolic acids and flavonols) contained in the 3 co-products obtained during the process were made between crude extracts, cross-flow microfiltration extracts and reverse osmosis concentrated extracts. Individual phenol compounds found in the products obtained were characterized and quantified by HPLC-DAD and by HPLC-MS2. Among the 11 phenol compounds identified in the water-extracts, 3 have been already identified in the literature (2 phenolic acids and 1 flavonol), and 8 new compounds, in noticeable amounts, have never been cited. We have confirmed the presence of phenolic acids such as 3,4,5-trihydroxybenzoic (gallic acid), 3,4-dihydroxybenzoic (protocatechuic acid) and of quercetin. We have characterized for the first time the presence of 2-hydroxy 5-[(3,4,5 trihydroxyphenyl) carbonyl oxy] benzoic acid and of 7 other flavonols belonging to the quercetin, kaempferol and isorhamnetol compound families. Using both LCMS and NMR analyses, they have been identified and quantified as: rutin, quercetin 3-0-glucoside, quercetin 3-0-galactoside, quercetin trihexoside, quercetin 3-0-robinobioside, kaempferol rhamnosylhexoside and isorhamnetol rhamnosyl-hexoside. (C) 2011 Elsevier B.V. All rights reserved