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Li., Y., Bolle, F., Steenhout, A.
Release of metals from ceramic articles in contact with food: effects of simulant, pH, temperature, contact duration and migration times

Directive 84/500/EEC (a regulation which specifies migration limits of lead (Pb) and cadmium (Cd) from ceramic articles intended to come into contact with food), is currently under revision by the European Commission, both for defining new Specific Migration Limits (SMLs) for Pb and Cd and for considering an extension to other elements, with validated testing methods. In this study, we investigated how much various parameters (nature of acid as simulants, pH, temperature, contact duration and repeated exposure) influence the release of metals from decorated ceramic articles during their use. The amounts of a series of 17 elements (including lithium, aluminium, chromium, barium, lead and cadmium) leaching from ceramic articles were measured simultaneously by ICP-OES. For each piece of ceramic vessel under testing: (1) the amounts of metals released rose with a decrease in pH (in the range-2.05- 2.97) in a non-linear mode, but this growth will not continue as much as the rise of the amount of hydrogen ions; (2) The amounts decreased with the repeated migration tests. Detailed studies of migration kinetics and behaviour at three temperatures (20°C, 40°C and 60°C) confirmed a rise with longer contact time, according to a logarithmic curve. Our data indicate that it is necessary to revise the Directive beyond the case of Pb and Cd, and to define SMLs for the potential migration of a series of metals. The test conditions with respect to all the parameters studied are discussed.

Menkissoglu-Spiroudi, U., Papadopoulou, E. S., Karpouzas, D. G.
Phospholipid fatty acid (PLFA) analysis and its applications in the study of pesticides effects on soil microbial diversity

Phospholipid fatty acids (PLFAs) analysis is a robust method for characterizing the composition of soil microbial communities. This method has been used as a reliable measure of the soil microbial biomass and also for assessing the impact of agronomic practices, pesticide applications and heavy metal pollution on the structure of the soil microbial community. The variation of phospholipids between eukaryotes and prokaryotes and among many prokaryotic groups as well as their rapid degradation after cell death, make PLFAs very useful indicators of the living microbial community. An optimized protocol for the extraction of PLFAs has been developed and validated, considering the types of extraction solvent and buffer, the extraction time and soil pH, on the quantity and the type of the PLFAs extracted from soils.
We report on PLFA analysis used from our research group in various studies to provide a thorough insight into the unknown impact of pesticides applied for different purposes, on the structure and function of the soil microbial community. Briefly we present results from studies i) to assess the impact of pesticides found in wastewaters of Fruit Packaging Plants and disposed in agricultural land, on soil microorganisms. ii) to assess the soil microbial ecotoxicity of selected bio-pesticides, comparatively with synthetic pesticides, and iii) to evaluate side effects of bioactive plant extracts or soil incorporated plants used as bio-nematicides, on the overall soil microbial community.

Botitsi, E., Antoniou, S., Tsipi, D.
Large scale multi-residue methods by gas and liquid chromatography-mass spectrometry for the determination of pesticide residues in food matrices

Nowadays, more than 1600 pesticides belonging to more than 100 chemical classes are in use worldwide for food production. In the EU, Regulation (EC) 396/2005 sets maximum pesticide residue limits in food (MRLs), the majority of which ranges over the concentration range 0.01-1 mg / kg. Large scale multi-residue methods based on general extraction procedures in combination with hyphenated instrumental analysis techniques such as gas and liquid chromatography with mass spectrometry are currently used in analytical laboratories working in the field of Pesticide Residues Analysis. In our laboratory, a multi- residue method based on QuEChERS method in combination with LC-MS/MS and GC-MS/MS techniques has been developed for the detection and quantification of pesticide residues, parent compounds and their metabolites, in various food matrices, fulfilling the performance criteria established in the European Union guidelines (SANTE Doc. No 11945/2015). A LC-MS/MS method using QqQ-MS technology in the SRM acquisition mode has been developed for the analysis of more than 250 compounds. Additionally, a GC-MS/MS method using Ion-Trap MSn technology has been applied for the determination of more than 80 GC-amenable compounds. More than 2000 pesticide/food commodity combinations have been validated using the LC- and GC-MS/MS methods, achieving recoveries in the range 70-120% with reproducibility values in terms of relative standard deviations less than 20%; limits of quantification of 0.01mg/Kg were established in most of the cases. Both methods have been successfully applied for the monitoring of multiclass pesticide residues in food samples in the frame of National and EU - Multi Annual Coordinated Control Programs.

Miliadis, G., Tsiantas, P., Paraskevaidi, K., Siragakis, G.
Uncertainty evaluation of parameters used in LC-MS/MS system suitability for the determination of pesticide residues

Parameters used to assess LC-MS/MS system suitability for the determination of the concentration of pesticide residues in food are the retention time, the ion ratio, the signal to noise ratio and the slope of the calibration line.
The EU tolerance values of the first two of these parameters have changed more than one time during the last years in the SANTE Document (last edition 11945/2015), they are differentiated from the respective tolerances mentioned in the Commission Decision 657/2002, and have been subject of debate.
In the present study system suitability parameters of LC-MS/MS were evaluated under the same LC- MS/MS conditions at concentration 0.01µg/mL, over 28 months’ period. Six representative compounds were used for this purpose and the respective control charts were constructed. The uncertainty values of these parameters were evaluated and compared to respective values of the literature.

Pina, A., Begou, O., Kanelis, D., Gika, H., Kalogiannis, S., Tananaki, C., Zotou, A., Theodoridis, G.
Metabolic profiling of royal jelly as a tool for the characterization of royal jelly

Royal Jelly (RJ) represents a high value food commodity with recognized nutraceutical and pharmacological properties. The chemical composition of RJ has been studied by several researchers, however data available in the literature are highly variable due to the intrinsic variability of this bee product and the various analytical methods applied. In food science, metabolomics have recently risen as a tool for quality and safety of raw materials and final products. In this study a LC-MS/MS metabolite profiling method was developed and validated for the efficient separation and quantification of small polar metabolites in the RJ. The investigated compounds were hydrophilic metabolites such as amino acids, sugars, organic acids, nucleosides, amines and vitamins. Chromatography was optimized to achieve separation of 88 selected metabolites over a period of 21 mins. The method was applied for the analysis of RJ samples with the aim to provide additional information on its metabolite content. A total of 64 metabolites were detected and 41 of them were quantified. Furthermore the results were processed statistically in order to identify the possible effect of beekeeping manipulations in the produced product. Classification of RJ samples according to the type of feeding was carried out using univariate and multivariate statistical analysis, based on the peak area variation of the metabolites. The statistical analysis revealed significant differences in the metabolite profiles of the samples that derived from the feeding experiments suggesting that profiling of hydrophilic content could provide a useful tool for detecting the effect of bee feeding in the composition of RJ.

Fotiou, M., Kyrkou, C., Tsakoumaki, F., Dimitropoulou, A., Virgiliou, C., Fotakis, C., Athanasiadou E., Loukri, A., Papadopoulos, S., Stamkopoulos, A., Gika, H., Theodoridis, G., Athanasiadis, A. P., Biliaderis, C. G., Zoumpoulakis, P., Michaelidou, A. M.
A pilot study to explore the link between habitual diet and urinary biomarkers during pregnancy

The aim of this pilot study was to link habitual red meat consumption and protein intake to previously established urinary biomarkers, in a group of pregnant woman. Conventional chemical analyses and metabolomics were employed to assess the maternal urine fingerprint. The % of energy derived from meat intake was correlated with urea and creatinine levels, protein intake (g) with alanine and urea concentrations, while animal protein (g) with alanine levels. Maternal pre- pregnancy BMI was associated with alanine levels. There is a link between maternal dietary intake and urinary biomarkers.

Eftimov, T., Ispirova, G., Koroušić Seljak, B., Korošec, P.
A semi-automatic system for classifying and describing foods according to FoodEx2

In this paper, we present results of the evaluation of a semi-automatic system for classifying and describing foods according to FoodEx2 using datasets from three European countries. The proposed system is an integration of methods from machine learning, natural language processing and probability theory. It obtained an accuracy of 91% for the classification part and 78% for the description part. The usage of the system can be a link between food consumption and food composition data as the transformation from food intake into nutrient intake can be automatically made.

Castanheira, I., Zoani, C., Roe, M., Ollilainen, V., Presser, K., Finglas P. M.
Development of the Guidelines for Assessment of Methods of Analysis (GAMA) – an online Wiki resource for food compilers and total diet studies

Analytical methodology has an important influence on data quality, butfood composition data compilersare often not experienced analysts, therefore detailed assessment criteria and guidance are required for the evaluation ofanalytical data from multiple sources. The ‘Guidelines for Assessment of Methods of Analysis (GAMA)’ werecompiled and presented as an online WIKI resource, covering comprehensive details on analytical methods for macronutrients, minerals, vitamins and trace elements, and madeavailable to users to support the EuroFIR data quality evaluation system and other food composition data compilation requirements.Information on analytical methodologiesfor each nutrient was collated and edited from scientific literature, international standards, and quality control procedures, and also included hyperlinks to additional, more detailed resourcesthat can be accessed using full text searches.
The GAMA Wiki was further enhanced for selected prioritized contaminants in the Total Diet Study project (TDS; EUFP7) to include all relevant information regarding analytical measurement of analytes that are targeted within total diet studies, such as official methods of analysis, selected scientific literature, reference material producers, available reference materials. Twenty-two new analytes were prioritised and added during the TDS project, including Mn, Se, Cu, Hg, Pb, As, Cd, radionuclides, dioxins, PCBs, acrylamide, PBDEs and PAHs.
The GAMA Wiki is a valuable tool for compilers and users to access information onanalytical methodology in relation to quality of analytical data. The user-friendly and accessible WIKI format is a usefultool for preparing and disseminating information to a variety of users. We are currently planning to interface the Wiki to the new METROFOOD-RI, and extend its coverage, functionality and use to additional researchers.

Westenbrink, S., Kadvan, A., Korousic Seljak, B., Möller, A., Ireland, J., Glibetic, M., Mantur, A., Roe, M., Finglas P.
The development of FoodEXplorer – A EuroFIR data interchange tool for searching and retrieving multiple food composition databases (FCDB)

The EuroFIR eSearch facility prototype was built and tested during theEuroFIR NoE project (EU FP6) with a vision to connect pan-European food information, and was shown to be an excellent proof of concept for exchange of food composition data. A new and improved version of the web-based tool was subsequently developed, and renamed as FoodEXplorer.The functionality, user interface and underlying database for FoodEXplorerwere reconstructed and recoded with new features that were added to or improved from the prototype, includingimproved user interfaces and data downloads via the EuroFIR Food Transport Package.The improvements also allowed closer integration with other tools included inthe EuroFIR food information platform, such asFoodCASE that is used for food composition database management, food data thesauri including LanguaL, and FoodBasket, which is asimple recipe calculation tool. FoodEXplorer supports both simple and advancedsearches to provide complex food information to a wide spectrum of food and nutrition experts (such as food compilers, dieticians, scientists, policy makers etc.) as well as non- expert commercial users.Itallows comparison of data fromdifferent food composition datasets and data exports in XML (Food DataTransport Package) and XLS (MS Excel) formats. The collection of food compositiondatabases behind FoodEXplorer is also used for dedicated EuroFIR WebServices that can deliver food information for other European projects.Integrated EuroFIR tools facilitate the future development of the Food, Nutrition and Health Research Infrastructure (eRI) that willsupport a wide range of end users (researchers, policy and commercial).

Page 257 of 977 Results 2561 - 2570 of 9762