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Villenave-d'Ornon, France

Pons M.,University of Bordeaux Segalen | Dauphin B.,University of Bordeaux Segalen | La Guerche S.,University of Bordeaux Segalen | Pons A.,University of Bordeaux Segalen | And 7 more authors.
Journal of Agricultural and Food Chemistry | Year: 2011

Analysis of wines from different grape varieties marked by sometimes intense aromatic nuances of fresh mushroom was performed by gas chromatography coupled with olfactometry. This analysis has led to the identification of several odoriferous zones, which were recalling a fresh mushroom odor. Two trace compounds responsible for these odoriferous zones, 1-nonen-3-one and 1-octen-3-one, have been identified and their content has been determined by using either a multidimensional gas chromatography technique coupled to olfactometry and mass spectrometry detection (in the case of 1-nonen-3-one) or the preparation of the derivative with O-2,3,4,5,6- pentafluorobenzylhydroxylamine hydrochloride in the presence of the deuterated form, as the internal standard (in the case of 1-octen-3-one), then gas chromatography coupled to mass spectrometry detection. The assays allowed the quantification of these compounds at concentration levels sometimes well above their detection and recognition olfactory threshold. We show that adding nitrogen compounds to the altered wines, such as an amino acid (glycine) or a tripeptide (glutathione), led to lower concentrations of 1-octen-3-one in wines and diminished smell of fresh mushrooms. The study of the reaction in a model medium, whose composition is close to wine, by liquid chromatography coupled to mass spectrometry demonstrated the formation of adducts between 1-octen-3-one and glycine, and 1-octen-3-one and glutathione characterized by NMR. © 2011 American Chemical Society.

Bagheri T.,Islamic Azad University at Gorgan | Bagheri T.,Gonbad University | Imanpoor M.R.,Gorgan University of Agricultural Sciences and Natural Resources | Jafari V.,Gorgan University of Agricultural Sciences and Natural Resources | Bennetau-Pelissero C.,ENITA de Bordeaux
Animal Reproduction Science | Year: 2013

A long-term feeding experiment was conducted to investigate the inclusion of soybean meal in diets for goldfish (Carassius auratus) on fish reproduction. In the present study, 20 weeks after hatching, goldfish with an initial average weight of 2±0.03g (mean±SD) were divided into 12 groups (three tanks per dietary treatment) and fed 400gkg-1 crude protein diets. The four experimental diets were as follows: diet 1, fish meal (FM); diet 2, 35% soybean meal (SBM35%); diet 3, 65% soybean meal (SBM65%); diet 4, 100% soybean meal (SBM100%). After feeding with experimental diets, the impact on reproduction was investigated. In both males and females, the plasma testosterone (T) was significantly decreased, while 17β-estradiol (E2) levels were significantly increased. Levels of 17α, hydroxyprogesterone. (17-OH-P) did not differ as a result of soybean meal feeding in either males or females. The average number of eggs spawned and sperm quality were reduced on feeding with soybean inclusion. Histological examination showed impact on oocyte maturation progress and spermatogenesis process in female and male fish, respectively. In addition, feeding goldfish with soybean meal until maturation caused reduction in fertilization and hatching rates in parallel to increasing soybean meal inclusion. The results demonstrated that inclusion of soybean meal might cause sex hormone biosynthesis disruption and reproductive impairments in fish, ultimately decreased fertilization as well as hatching rates in the offspring. © 2013 Elsevier B.V.

Naumov G.I.,State Institute for Genetics | Naumova E.S.,State Institute for Genetics | Masneuf-Pomarede I.,ENITA de Bordeaux | Masneuf-Pomarede I.,French National Institute for Agricultural Research
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2010

Direct genetic testing for hybrid sterility unambiguously showed that the newly described yeast Saccharomyces arboricolus Wang et Bai is reproductively isolated from Saccharomyces cerevisiae, Saccharomyces bayanus, Saccharomyces cariocanus, Saccharomyces kudriavzevii, Saccharomyces mikatae and Saccharomyces paradoxus and, therefore, represents a new biological species of the genus Saccharomyces. Combined phylogenetic analysis of the rDNA repeat sequences (18S, 26S, ITS), nuclear ACT1 and mitochondrial ATP9 genes revealed that S. arboricolus, along with S. kudriavzevii and S. bayanus, is distantly related to the other four biological species. © 2010 Springer Science+Business Media B.V.

Masneuf-Pomarede I.,ENITA de Bordeaux | Bely M.,French National Institute for Agricultural Research | Marullo P.,SARCO | Lonvaud-Funel A.,French National Institute for Agricultural Research | Dubourdieu D.,French National Institute for Agricultural Research
International Journal of Food Microbiology | Year: 2010

Among Saccharomyces yeast, S. cerevisiae and S. bayanus var. uvarum are related species, sharing the same ecosystem in sympatry. The physiological and technological properties of a large collection of genetically-identified S. bayanus var. uvarum wine strains were investigated in a biometric study and their fermentation behavior was compared at 24°C and 13°C. The variability of the phenotypic traits was considered at both intraspecific and interspecific levels. Low ethanol tolerance at 24°C and production of high levels of 2-phenylethanol and its acetate were clearly revealed as discriminative technological traits, distinguishing the S. bayanus var. uvarum strains from S. cerevisiae. Although some S. bayanus var. uvarum strains produced very small amounts of acetic acid, this was not a species-specific trait. , as the distribution of values was similar in both species. Fermentation kinetics at 24°C showed that S. bayanus var. uvarum maintained a high fermentation rate after Vmax, with low nitrogen requirements, but stuck fermentations were observed at later stages. In contrast, a shorter lag phase compared with S. cerevisiae, higher cell viability, and the ability to complete alcoholic fermentation at 13°C confirmed the low-temperature adaptation trait of S. bayanus var. uvarum. This study produced a phenotypic characterization data set for a collection of S. bayanus var. uvarum strains, thus paving the way for industrial developments using this species as a new genetic resource. © 2010 Elsevier B.V.

Naumova E.S.,State Institute for Genetics and Selection of Industrial Microorganisms | Naumov G.I.,State Institute for Genetics and Selection of Industrial Microorganisms | Michailova Y.V.,State Institute for Genetics and Selection of Industrial Microorganisms | Martynenko N.N.,Moscow State University | Masneuf-Pomarede I.,ENITA de Bordeaux
Research in Microbiology | Year: 2011

Intraspecies polymorphism of the yeast Saccharomyces bayanus var. uvarum was studied using the polymerase chain reaction with a microsatellite primer (GTG)5. Sixty-nine strains of different origins were analyzed. There existed a correlation between PCR patterns of the strains and the source of their isolation: the type of wine and the particular winemaking region. Southern hybridization analysis revealed for the first time introgression between Saccharomyces cerevisiae and S. bayanus var. uvarum. Two strains isolated from alcoholic beverages in Hungary and identified by genetic analysis as S. bayanus var. uvarum were found to harbor a number of S. cerevisiae subtelomeric sequences: Y', SUC, RTM and MAL. © 2010 Institut Pasteur.

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