Influence of Different Yeast Strains on Metabolism of Tryptophan and Indole-3-Acetic Acid During Fermentation

The effect of supplementation of Riesling (Vitis vinifera L.) must with ammonium sulphate (AS) ontryptophan (Trp) and indole-3-acetic acid (IAA) metabolism during alcoholic fermentation with fourcommercial yeast strains (Uvaferm CEG, Lalvin Cross Evolution, Anchor VIN 13 and Anchor exoticSPH) were examined. AS addition reduced Trp uptake by yeasts from 1% to 15%. Wines produced byAnchor VIN 13 and Uvaferm CEG yeasts with AS addition had the highest concentrations of Trp (0.60and 0.59 mg/L respectively). Concentrations of total and bound IAA decreased during all treatments. Atthe end of fermentation the highest concentration of free IAA was measured in the control must inoculatedwith Anchor VIN 13 yeast (35.83 μg/L) and the lowest in the sample inoculated with Uvaferm CEG yeast(13.08 μg/L). Anchor VIN 13 yeast showed the strongest change in metabolism due to AS addition duringfermentation. 2-Aminoacetophenone (2-AAP) formation was not observed in all the studied wines

Coastal sea level monitoring in the Mediterranean and Black seas

Employed for over a century, the traditional way of monitoring sea level variability by tide gauges – in combination with modern observational techniques like satellite altimetry – is an inevitable ingredient in sea level studies over the climate scales and in coastal seas. The development of the instrumentation, remote data acquisition, processing, and archiving in the last decades has allowed the extension of the applications to a variety of users and coastal hazard managers. The Mediterranean and Black seas are examples of such a transition – while having a long tradition of sea level observations with several records spanning over a century, the number of modern tide gauge stations is growing rapidly, with data available both in real time and as a research product at different time resolutions. As no comprehensive survey of the tide gauge networks has been carried out recently in these basins, the aim of this paper is to map the existing coastal sea level monitoring infrastructures and the respective data availability. The survey encompasses a description of major monitoring networks in the Mediterranean and Black seas and their characteristics, including the type of sea level sensors, measuring resolutions, data availability, and existence of ancillary measurements, altogether collecting information about 240 presently operational tide gauge stations. The availability of the Mediterranean and Black seas sea level data in the global and European sea level repositories has been also screened and classified following their sampling interval and level of quality check, pointing to the necessity of harmonization of the data available with different metadata and series in different repositories. Finally, an assessment of the networks' capabilities for their use in different sea level applications has been done, with recommendations that might mitigate the bottlenecks and ensure further development of the networks in a coordinated way, a critical need in the era of human-induced climate changes and sea level rise.En prens

Kimia Dasar

319 hal.; ill.; 23c

Diversity and oenological characterization of indigenous Saccharomyces cerevisiae associated with Z ilavka grapes

The aim of this research was to identify the Saccharomyces spp. associated with A1/2ilavka grapes and to evaluate their enzymatic activities, H(2)S production and micro-fermentation performance. For this purpose, a total of 143 yeast strains isolated from three production areas of the Mostar wine region (Bosnia and Herzegovina) were studied and analysed. Firstly, yeasts were identified to genus level by growth on WL nutrient agar and the test of assimilation of lysine. Later, molecular identification at species level was carried out with RFLP analysis of 18S rDNA + ITS region, and at strain level with microsatellite-primed PCR (MSP-PCR). At physiological level yeast strains were grouped into different clusters by means of the Joining-Tree-Clustering-Method. All yeasts tested were identified as S. cerevisiae, resulting a total of 18 different strains. All of the investigated strains produced hydrogen sulphide, 89% were able to complete the fermentation, and none of them was able to synthesize killer toxins. Since enzymes play a very important role in wine aroma development, it was very encouraging that 33% of the strains were able to synthesize pectinolytic enzyme but only one produced beta-glucosidase. In the second part of the selection process two indigenous strains were compared with commercial yeast in a microvinification and A1/2ilavka wines with different profiles of volatiles were obtained. This research represents a first step in the selection of indigenous yeast strains from the Mostar region with the goal of maintaining the specific organoleptic characteristics of A1/2ilavka wine

Use of micro-PIXE to determine spatial distributions of copper in Brassica carinata plants exposed to CuSO4 or CuEDDS

A better understanding of the mechanisms that govern copper (Cu) uptake, distribution and tolerance in Brassica carinata plants in the presence of chelators is needed before significant progress in chelate-assisted Cu phytoextraction can be made. The aims of this study were therefore to characterise (S,S)-N,N′-ethylenediamine disuccinic acid (EDDS)-assisted Cu uptake, and to compare the spatial distribution patterns of Cu in the roots and leaves of B. carinata plants. The plants were treated with 30 μM or 150 μM CuSO4 or CuEDDS in hydroponic solution. Quantitative Cu distribution maps and concentration profiles across root and leaf cross-sections of the desorbed plants were obtained by micro-proton induced X-ray emission. In roots, the 30 μM treatments with both CuSO4 and CuEDDS resulted in higher Cu concentrations in epidermal/cortical regions. At 150 μMCuSO4, Cu was mainly accumulated in root vascular bundles, whereas with 150 μM CuEDDS, Cu was detected in endodermis and the adjacent inner cortical cell layer. Under all treatments, except with a H+-ATP-ase inhibitor, the Cu in leaves was localised mainly in vascular tissues. The incubation of plants with 150 μM CuEDDS enhanced metal translocation to shoots, in comparison to the corresponding CuSO4 treatment. Inhibition of H+-ATPase activity resulted in reduced Cu accumulation in 30 μM CuEDDS-treated roots and 150 μM CuEDDS-treated leaves, and induced changes in Cu distribution in the leaves. This indicates that active mechanisms are involved in retaining Cu in the leaf vascular tissues, which prevent its transport to photosynthetically active tissues. The physiological significance of EDDS-assisted Cu uptake is discussed

Use of micro-PIXE to determine spatial distributions of copper in Brassica carinata plants exposed to CuSO4 or CuEDDS

none13A better understanding of the mechanisms that govern copper (Cu) uptake, distribution and tolerance in Brassica carinata plants in the presence of chelators is needed before significant progress in chelate-assisted Cu phytoextraction can be made. The aims of this study were therefore to characterise (S,S)-N,N'-ethylenediamine disuccinic acid (EDDS)-assisted Cu uptake, and to compare the spatial distribution patterns of Cu in the roots and leaves of B. carinata plants. The plants were treated with 30μM or 150μM CuSO 4 or CuEDDS in hydroponic solution. Quantitative Cu distribution maps and concentration profiles across root and leaf cross-sections of the desorbed plants were obtained by micro-proton induced X-ray emission. In roots, the 30μM treatments with both CuSO 4 and CuEDDS resulted in higher Cu concentrations in epidermal/cortical regions. At 150μM CuSO 4, Cu was mainly accumulated in root vascular bundles, whereas with 150μM CuEDDS, Cu was detected in endodermis and the adjacent inner cortical cell layer. Under all treatments, except with a H +-ATP-ase inhibitor, the Cu in leaves was localised mainly in vascular tissues. The incubation of plants with 150μM CuEDDS enhanced metal translocation to shoots, in comparison to the corresponding CuSO 4 treatment. Inhibition of H +-ATPase activity resulted in reduced Cu accumulation in 30μM CuEDDS-treated roots and 150μM CuEDDS-treated leaves, and induced changes in Cu distribution in the leaves. This indicates that active mechanisms are involved in retaining Cu in the leaf vascular tissues, which prevent its transport to photosynthetically active tissues. The physiological significance of EDDS-assisted Cu uptake is discussed.noneCestone B.; Vogel-MIkus K.; Quartacci M.S.; Rascio N.; Pongrac P.; Pelicon P.; Vavpetic P.; Grej N.; Jeromel L.; Kump P.; Necemer M.; Regvar M.; Navari-Izzo F.Cestone, B.; Vogel MIkus, K.; Quartacci, M. S.; Rascio, Nicoletta; Pongrac, P.; Pelicon, P.; Vavpetic, P.; Grej, N.; Jeromel, L.; Kump, P.; Necemer, M.; Regvar, M.; Navari Izzo, F