EXTRACELLULAR POLYSACCHARIDES OF POTATO RING ROT PATHOGEN

Many bacteria, including phytopathogenic ones produce extracellular polysaccharides or exopolysaccharides which are universal molecules. Causal agent of potato ring rot, Clavibacter michiganensis subspecies sepedonicus, secretes exopolysaccharides which role in pathogenesis is poorly investigated. The aim of our research is to ascertain the composition and structure of Clavibacter michiganensis subspecies sepedonicus exopolysaccharides. Exopolysaccharides of Clavibacter michiganensis subspecies sepedonicus are determined to consist of 4-6 anionic and neutral components which have molecular weights from <1 kDa to >700 kDa. Glucose is a major monomer of polysaccharides and arabinose, rhamnose and mannose are minor monomers. Glucose is present in α-Dglucopyranose and β-D-glucopyranose configurations. Calcium is determined to be a component of exopolysaccharides. Components of exopolysaccharides of potato ring rot pathogen are probably capableto associate via calcium ions and other ionic interactions that may result in a change of their physiological activity. Further studies of Clavibacter michiganensis subspecies sepedonicus exopolysaccharides composition and structure can serve a base for the synthesis of their chemical analogues with elicitor action

COHOUSING

Cílem projektu bylo přenést koncept cohousingu, který je určený převážně pro periferie velkých měst přímo do centra města, spojit tradiční bytový dům se spolu-bydlením v rámci jednoho bloku. Nalezení vhodného poměru spolu-bydlení pro mladé a tradičního bydlení (bytový dům) v rámci jednoho městského bloku.The aim of the project was to bring the concept of cohousing , which is typically existing on the peripheries of the big cities, to the city center and try to join cohousing with classic apartment building in one city block

ENHANCEMENT OF PROFESSIONAL COMPETENCE OF EDUCATIONAL PROFESSIONALS IN THE CONTEXT OF ORGANIZING METHODOLOGICAL SUPPORT

The article is dedicated to the issues of improving the professional competencies of educational professionals through the organization of methodological support within the framework of creating a unified system of professional development and implementing the “Modern School” federal project. The authors disclose the specifics of methodological support for educators aimed at identifying professional deficits, employing individual educational route technologies, and developing competence enhancement programs. The authors present a model of organizing methodological support for educational professionals, including a component for future educators, thereby proving the importance of organizing methodological interaction with practicing educators to shape a new type of university graduate capable of continuous professional growth. The authors are convinced that involving educators and students, i.e. future educators, in scientific and methodological events, including joint planning, contributes to the development of analytical skills and methodological culture, enhances professional mastery, fosters the establishment of conscious professional positions, and improves communication formats. Special attention is given by the authors to the application of normative and legal foundations for the organization of a multi-level methodological support system involving various methodological structures, professional communities, and subject associations. The article is addressed to the faculty and staff of the supplementary professional education system, research workers, doctoral students, teachers, and students of educational institutions, as well as those interested in educational issues in the field of improving the professional competence of educational professionals

Trace Elements Analysis of Tunisian and European Extra Virgin Olive Oils by ICP-MS and Chemometrics for Geographical Discrimination

The aim of this study was to investigate the levels of trace elements in olive oils from different locations and their use for geographical authentication. Concentrations of seventeen elements were determined in a total of 42 olive oils from Tunisia, Spain (Basque country), and southern France, and in nine soil samples from Tunisia by quadrupole inductively plasma mass spectrometry. The compilation of appropriate techniques integrated into the analytical procedure achieved a precision (RSD) between 2% and 15% and low limits of detection (between 0.0002 and 0.313 µg kg−1). The accuracy of the analytical method applied for olive oil analysis was evaluated using SRM NIST 2387 Peanut butter. The recoveries obtained after microwave-assisted digestion for the certified elements ranged between 86% and 102%. Concentrations of non-certified elements (V, Cr, Co, Ni, Ba, Rb, Sr, Cd, Pb, and As) were presented. The use of Pearson correlation applied on paired Tunisian oil/soil samples has shown that several elements (Mg, Mn, Ni, and Sr) were significantly correlated. The multivariate statistics using principal component analysis have successfully discriminated against three studied origins. The most significant variables were the elemental concentrations of Cu, Cr, Fe, Mn, Sr, V, and Zn. This study shows the potential of applying trace elements profiles for olive oil geographical discrimination.This research was funded by European Project TunTwin from the Horizon 2020 Framework program of the European Union under grant No. 952306. It was also funded by the French ANR EquiPex MARSS project with a contribution of the METROFOOD ESFRI project. This work was partially supported by the Euskadi/Nouvelle Aquitaine/Navarra Eurorregion through the research project ISOTOPO (with agreement no. 2020/3). The financial support of a Ph.D. grant for Emna G. Nasr has been provided by the “Excellence Eiffel” scholarship of Campus France, the European project “TunTwin” and the scholarship “bourse d’alternance” of University Tunis El Manar, Ministry of Higher Education and Scientific Research in Tunisia

Determination of 87Sr/86Sr isotopic ratio in olive oil and pomace using multicollector-ICPMS; analysis of pomace residues as a simpler approach for determination of 87Sr/86Sr ratio in olive oil with low Sr content

This study presents an analytical procedure for measuring the 87Sr/86Sr isotopic ratio in olive oil and pomace using multicollector-inductively coupled mass spectrometry (MC-ICPMS). The developed method combines liquid-liquid extraction with an acid solution and degradation of organic residues in the extract by dry ashing and oxidation by H2O2 and HNO3. The method enabled 87Sr/86Sr ratios to be obtained in olive oil with Sr content as low as 0.2 ng/g, with a precision of 54 ppm. The method’s validity was confirmed by an interlaboratory comparison using NIST SRM 2387, providing the first data on its elemental Sr (2380 ± 230 ng/g ; n = 10), and 87Sr/86Sr isotopic composition (0.70908 ± 0.00004 ; n = 14). The procedure was applied to olive oil and pomace samples, showing that they have an identical 87Sr/86Sr ratio, which was consistent with that determined in soils from the same orchards. The results thus revealed that Sr isotopic ratios of olive oil and pomace can both be used in geographical traceability studies of olive oil, which means that, instead of processing large volume of oil, characteristic 87Sr/86Sr signatures of olive oil can be more easily obtained by analyzing small quantities of pomace obtained by centrifuging the oil

The stability of major and trace element concentrations from musts to Champagne during the production process

Thirty-nine Champagnes from six different brands originating from the AOC Champagne area were analyzed for major and trace element concentrations in the context of their production processes and in relation to their geographical origins. Inorganic analyses were performed on the must (i.e., grape juice) originating from different AOC areas and the final Champagne. The observed elemental concentrations displayed a very narrow range of variability. Typical concentrations observed in Champagne are expressed in mg/L for elements such as K, Ca, Mg, Na, B, Fe, A, and Mn. They are expressed in µg/L for trace elements such as Sr, Rb, Ba, Cu, Ni, Pb Cr and Li in decreasing order of concentrations. This overall homogeneity was observed for Sr and Rb in particular, which showed a very narrow range of concentrations (150 &lt; Rb &lt; 300 µg/L and 150 &lt; Sr &lt; 350 µg/L) in Champagne. The musts contained similar levels of concentration but showed slightly higher variability since they are directly influenced by the bedrock, which is quite homogenous in the AOC area being studied. Besides the homogeneity of the bedrock, the overall stability of the concentrations recorded in the samples can also be directly linked to the successive blending steps, both at the must level and prior to the final bottling. A detailed analysis of the main additives, sugar, yeast and bentonite, during the Champagne production process, did not show a major impact on the elemental signature of Champagne

Specificity and origin of the stability of the sr isotopic ratio in champagne wines

The 87Sr/86Sr ratio of 39 Champagnes from six different brands, originating from the whole “Appellation d’Origine Contrôlée” (AOC) Champagne was analyzed to establish a possible relation with the geographical origin. Musts (i.e., grape juice) and base wines were also analyzed to study the evolution of the Sr isotopic ratio during the elaboration process of sparkling wine. The results demonstrate that there is a very homogeneous Sr isotopic ratio (87 Sr/86 Sr = 0.70812, n = 37) and a narrow span of variability (2? = 0.00007, n = 37). Moreover, the Sr concentrations in Champagnes have also low variability, which can be in part explained by the homogeneity of the bedrock in the AOC Champagne. Measurements of the87 Sr/86 Sr ratio from musts and base wines show that blending during Champagne production plays a major role in the limited variability observed. Further, the87 Sr/86 Sr of the musts were closely linked to the87 Sr/86 Sr ratio of the vineyard soil. It appears that the87 Sr/86 Sr of the product does not change during the elaboration process, but its variability decreases throughout the process due to blending. Both the homogeneity of the soil composition in the Champagne AOC and the blending process during the wine making process with several blending steps at different stages account for the unique and stable Sr isotopic signature of the Champagne wines.Centre de Spectrometrie de Masse pour les Sciences de la Réactivité et de Spéciatio