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Kalčic F., Fraňková A., Maršík P., Jiralová K., Havlík J., Hroncová Z., Klouček P.
Evaluation of extraction methods for metabolite profiling of Apis mellifera using NMR spectroscopy

Metabolite profiling provides an insight into a situation in a cell as metabolites represent status of the cell, tissue or whole organism. NMR, despite its relatively low sensitivity, offers high reproducibility, short acquisition time, possibility of unknown metabolite identification, and quantitative information. Honeybees (Apis mellifera), the most important insect in the world regarding the food production, suffer from major unresolved phenomena, like colony collapse disorder and overwintering problems, which threaten their economic utilization and food production chain as such.
In this study, we have developed and evaluated extraction protocols for NMR based profiling. We have evaluated different pre-extraction procedures –intestinal tract removal, separate head and body extraction and freeze drying, and five different extraction solvents plus five combinations. Proton NMR spectra (500 MHz) were processed using PCA analysis. Identification of compounds was based on comparison with the spectra of pure standards.
Inter-individual variations were negligible, but the intestinal tract removal was necessary. Freeze-drying as well as separate head and body extraction did not proved beneficial for the final results, and therefore are not recommended. Major amino acids, sugars and organic acids were identified. Comparison of their relative quantification in different solvents revealed that combination of water/acetonitrile 1:1 was superior in yield of most of the major compounds. On the other hand, water/methanol 1:1 showed better peak resolution despite the lower yield.
For NMR-based metabolomics the metabolite extraction is the most critical step. This study could contribute to clarification of phenomena such as colony collapse disorder or longevity of honeybees.

Fotakis C., Proestos C., Sinanoglou V. J., Zoumpoulakis P.
NMR metabolomics and spectrophotometric studies to infusions and decoctions of plant species to assess and compare the metabolic and antioxidant profiles

NMR metabolomics and spectrophotometric studies (Folin–Ciocalteu, FRAP, ABTS) are implemented to infusions and decoctions of plant species to assess and compare the metabolic and antioxidant profiles for each botanical family. Multivariate and univariate data analyses highlighted the differences among the samples and pinpointed specific classes of compounds for each plant species as well as infusions and decoctions. The identified phenolic compounds by NMR, as well as the antioxidant profile, framed a trend of increased values in infusions compared to the decoctions. Furthermore, the infusion procedure positively affected the extractability of the phenolic compounds compared to decoctions. The highest total phenolic content (TPC) was found in Mentha spicata, while the lowest in Matricaria chamomilla preparations, irrespective of the preparation method. The preparation time for the decoctions was examined showing that the 15 min preparations were generally found richer in phenolics and of higher antioxidanactivity.

Consonni R., Cagliani L. R.
NMR metabolomics in food authentication

NMR (Nuclear Magnetic Resonance) represents the elective technique for structure elucidation of molecules and is particularly suited to analyze complex mixtures like foods. NMR provides the identification of a wide range of chemical compounds simultaneously, revealing potential markers or disclosing sophisticated frauds. The great economic values of high quality or guaranteed foods demands highly refined characterization tools. In this context metabolomics represents a privileged approach for modern analytical studies in the next decades.

Theodoridis, G.
Standardising Analytical Metabolomics. Focus in Food Analysis

Metabolomics represents an upcoming, interdisciplinary field in with applications spanning across biomedical, food and environmental sciences. In food sciences metabolomics can offer unique advantages by combing analyses, revealing trends in complex data, identifying new markers and creating new tools for quality control of foods.
As the field is still rather new, practically its sub-disciplines are still evolving: biochemical pathway annotation, chemical analysis, data interpretation are all in the development phase. The analytical part for metabolomics is highly demanding due to complexity of the composition of the samples, the high diversity of molecular structures and physico-chemical properties of the analysed molecules, the large differences in the concentration ranges between the different metabolites. These issues result to poor standardization of methods and reporting and thus hinder large scale application (epidemiology level), leading to fragmentation of research efforts. MS- based results obtained in different laboratories or instruments cannot be effectively compared or correlated. These issues call for large collaboration between metabolomics laboratories to set benchmarks, harmonise methods and standardize protocols and reports. Promotion of inter-laboratory tests is of utmost importance to compare findings. The presentation will highlight such needs, propose ideas and will call for common action which is necessary to overcome such issues, coordinate metabolomics experimentations, promote data sharing and comparison of analytical & sample preparation methods and metabolomics software, implement Quality Assurance/Quality Control/ (QA/QC) and the development and acceptance of common understanding/definitions.

Ioannis P. Gerothanasis
Chemical analysis, monitoring of dynamic changes, metabolomics and "in cell" applications of NMR in natural products and food chemistry: Is the role of metrology underestimated?

A critical overview of recent developments of NMR spectroscopy in natural products and food chemistry will be provided with emphasis in the following applications:
(i) chemical analysis of extracts without isolation or derivatization steps [1-5],
(ii) ‘in situ’ direct monitoring of dynamic changes of metabolites as a function of solvent and temperature [6],
(iii) aromatic C–H activation of flavonoids in aqueous solution at neutral pH and ambient temperatures [7],
(iv) rapid ‘in situ’ analysis of enzymatic reaction products and enriching the biological space of natural products, through real time biotransformation monitoring [8] and
(v) in-cell NMR in decoding the apoptotic activity of flavonoids with the Bcl-2 family of proteins [9].
Despite the significant advantages in methodology and the fact that NMR is a potentially primary analytical technique for qualification, much effort should be made in the future so that international compatibility can be achieved for a wide range qualification, compatibility range of chemical constituents in natural products and in food chemistry. Selected examples of certified reference materials will be provided.

Nicola Martinelli, Mariella Annese, Silvana Milella, Vito D'Onghia
Development of innovative knowledge frameworks for the protection and enhancement of rock habitat in a municipal planning experience

The knowledge produced during the process of urban planning and land-use planning is a source of information of great interest, useful for planning actions aimed at enhancing the cultural heritage, safeguarding autogenous resources and developing the territory. The uniqueness of the heritage of rock habitat, as a sign of the historical-settlement stratification of the anthropic cavities and of the churches conceived as testimonies of the VI and VII century AD, true symbols of pagan and Christian religiosity, represents a perspective of protection and development in a tourist key on a territory, such as that of Massafra in the province of Taranto, with a strong environmental resilience. The drafting of the new urban planning instrument, such as the Urban Planning Plan (PUG), expresses the need for careful planning for urban policies focused on the issues of development, protection and socioeconomic development of the local heritage.

Fabrizio Terenzio Gizzi, Giovanni Leucci
Global research patterns on Ground Penetrating Radar (GPR)

The paper deals with the analysis of worldwide research patterns concerning Ground Penetrating Radar (GPR) during 1995-2014. To reach the fixed aim the Thomson Reuters' Science Citation Index Expanded (SCI-EXPANDED) and the Social Sciences Citation Index (SSCI) accessed via the Web of Science Core Collection were the two bibliographic databases taken as a reference. The authors pay attention to the document typology, the publication trend and citations, the subject categories and journals, the most cited articles, the countries and the institutions involved, and the hot issues. As concerns the main research subfields involving the GPR use, they were five in the 20-years period investigated in this article. We refer to the physical-mathematical (PM), sedimentological-stratigraphical (SS), civil engineering/engineering geology/cultural heritage (CE/EG/CH), hydrological (HD), and glaciological (GL) subfields. The outcomes of this study can contribute both to get an insight into the changes made in GPR related research over the time and supply clues about the future research trends.

Giuseppina Uva, Sergio Ruggeri, Valentino Sangiorgio, Fabio Fatiguso
Structural vulnerability assessment of masonry churches supported by user-reported data

Ancient masonry churches represent a particularly vulnerable architectural typology, and the experience progressively acquired during post–earthquake surveys has pointed out that recurrent damage patterns and main failure mechanisms can be identified and studied by separately looking at the different architectural "macro–elements": façade, nave, aisle, transept, lateral chapel, dome, bell tower. In the last few years, the macro-element approach has been extensively and fruitfully applied to perform preliminary vulnerability assessments, by recognizing the correspondence between each structural macroelement and the most recurrent collapse mechanisms associated. This type of approach has been also incorporated in the Italian Guidelines for the seismic vulnerability analysis architectural heritage. In the paper, the above-mentioned method is applied by a Multi-Criteria Decision Analysis approach designed for the support of decisions involving expert judgements and several alternatives. The peculiarity of the system is the retrieval of additional data by a User-reporting Application. In the specific case of masonry churches, the application involves the integration of these data in the vulnerability macroelement approach.

Luciano Ombres, Antonio Iorfida, Stefania Mazzuca, Salvatore Verre
Bond analysis of thermally conditioned FRCM-masonry joints

Results of an experimental investigation on bond between thermally conditioned FRCM-masonry joints is presented and discussed in the paper. Single lap shear tests were conducted on clay brick specimens strengthened with different FRCM systems (basalt, steel and PBO-FRCM systems). Before testing specimens were thermally conditioned by exposure to different temperature values: 20°C (ambient temperature), 100 °C, 150 °C and 200°C. The thermal treatment was developed in this way: strengthened specimens were kept in oven and exposed to constant temperature over a period of three hours, then, they were removed and cooled down freely to ambient temperature. After the thermal treatment, specimens were tested at ambient temperature. Experimental results allow to evaluate the influence of the thermal conditioning on the local bond-slip response of strengthened specimens.

Page 258 of 977 Results 2571 - 2580 of 9762