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San Juan de la Rambla, Spain

Manzano P.,University of Valladolid | Arnaiz E.,University of Valladolid | Diego J.C.,University of Valladolid | Toribio L.,University of Valladolid | And 4 more authors.
Journal of Chromatography A | Year: 2011

A method to separate FAME and the linoleic and linolenic acids isomers by GCxGC using an apparatus equipped with a capillary flow technology (CFT) based modulator and a FID detector has been developed. Four different column combinations (one conventional and three inverted phase sets) were used in these experiments. The conventional set first involved a DB5-MS non-polar column followed by a highly polar HP-INNOWax column in the second dimension. The inverted phase set comprised of a highly polar BPX-70 column in the first dimension and a non-polar ZB5-MS column for the second dimension. Furthermore, the influence of the length of the second dimension column on FAME isomer separation was studied in the inverted phase sets, along with other parameters like the modulation time and column flow. The best results in terms of the time required for the analysis and number of FAME identified with the inverted set were achieved with the shorter second dimension column. After supercritical fluid extraction, the method was applied to identify FAMEs in broccoli leaves from three different cultivars (Naxos, Nubia and Viola). © 2011 Elsevier B.V. Source


Ongay S.,Institute of Organic Chemistry CSIC | Martin-Alvarez P.J.,Institute of Industrial Fermentations CSIC | Neusu C.,Aalen University of Applied Sciences | de Frutos M.,Institute of Organic Chemistry CSIC
Electrophoresis | Year: 2010

α-1-Acid glycoprotein (AGP) is a highly heterogeneous protein that presents a vast number of isoforms (molecules of the protein differing in its peptidic and/or glycosidic moieties). In recent years, several authors have studied the potential use of AGP as a cancer biomarker. These studies focus on the correlation of different features of AGP structure (i.e. fucosylation, antennarity) with cancer or on the total protein blood concentration. In this study, the potential of CZE-UV and CZE-ESI-MS analysis of intact AGP isoforms to study the correlation of this protein with bladder cancer is shown. Samples from 16 individuals (eight healthy, eight bladder cancer) were analyzed and characterized in great detail including data on intact protein isoforms and on released glycans. The analytical data were evaluated employing different statistical techniques (ANOVA; principal component analysis, linear discriminant analysis; and partial least squares-discriminant analysis). Statistical differences between the two groups of study were observed. The best results were obtained by linear discriminant analysis of the CZEESI-MS data for intact AGP isoforms (93.75% of correct classification). Due to MS characterization, it can be observed that differences between the samples are mainly due to higher abundance of AGP isoforms containing tri- and tetra-antennary fucosylated oligosaccharides in cancer patients. The results show the great potential of CE-MS in combination with advanced data processing for the use of intact protein isoforms as disease biomarkers. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Klejdus B.,Mendel University in Brno | Lojkova L.,Mendel University in Brno | Plaza M.,Institute of Industrial Fermentations CSIC | Snoblova M.,Mendel University in Brno | Sterbova D.,Mendel University in Brno
Journal of Chromatography A | Year: 2010

New hyphenated technique for the extraction and determination of isoflavones in sea and freshwater algae and cyanobacteria was developed. The method consists of sonication sample pretreatment, extraction by supercritical CO2 modified by 3% (v/v) of MeOH/H2O mixture (9:1, v/v) at 35MPa and 40°C for 60min, fast chromatography analysis by the means of Agilent 1200 Series Rapid Resolution and MS/MS determination. Agilent 1200 Series RRLC was used with Zorbax SB-CN chromatographic column (100mm×2.1mm, particle size 3.5μm), 3μl injection volume, mobile phase consisting of 0.2% (v/v) acetic acid in water (solvent A) and acetonitrile (solvent B) and used with linear gradient (30% B at 0min, from 0min to 3min up to 50% B, from 3 to 6min up to 80% B and from 6 to 10min down to 30% B). The flow-rate was 0.4mL/min, column oven temperature 35°C. MS detector Agilent Technologies 6460 Triple quadrupole LC/MS with Agilent Jet Stream was used in a negative ESI mode under following conditions: gas temperature 350°C, gas flow 13L/min, nebulizer gas pressure 50psi, sheath gas temperature 400°C, sheath gas flow 12L/min, capillary voltage was 4kV. Samples were analysed in the multiple reaction monitoring (MRM) mode. Eight isoflavone compounds were found for the first time in seven real samples of sea algae and in three control samples of freshwater algae and cyanobacteria. Usual optimisation study of extraction parameters was performed. Pressure and temperature optima for algae matrix are different from those obtained sooner for other matrices for most of the analytes, but the results of modifier optimisation study are in good accordance with those obtained sooner for spiked samples and red clover matrix. It seems that matrix has very small or no effect on the modifier selection. Two different approaches of sonication pretreatment were tested: sonication bath and the thorn instrument. In longer extraction time experiments, thorn sonication was more efficient and recovery of following supercritical fluid extraction was higher. © 2010 Elsevier B.V. Source


Garcia-Canas V.,Institute of Industrial Fermentations CSIC | Simo C.,Institute of Industrial Fermentations CSIC | Leon C.,Institute of Industrial Fermentations CSIC | Ibanez E.,Institute of Industrial Fermentations CSIC | And 2 more authors.
Mass Spectrometry Reviews | Year: 2011

The development of genetically modified crops has had a great impact on the agriculture and food industries. However, the development of any genetically modified organism (GMO) requires the application of analytical procedures to confirm the equivalence of the GMO compared to its isogenic non-transgenic counterpart. Moreover, the use of GMOs in foods and agriculture faces numerous criticisms from consumers and ecological organizations that have led some countries to regulate their production, growth, and commercialization. These regulations have brought about the need of new and more powerful analytical methods to face the complexity of this topic. In this regard, MS-based technologies are increasingly used for GMOs analysis to provide very useful information on GMO composition (e.g., metabolites, proteins). This review focuses on the MS-based analytical methodologies used to characterize genetically modified crops (also called transgenic crops). First, an overview on genetically modified crops development is provided, together with the main difficulties of their analysis. Next, the different MS-based analytical approaches applied to characterize GM crops are critically discussed, and include "-omics" approaches and target-based approaches. These methodologies allow the study of intended and unintended effects that result from the genetic transformation. This information is considered to be essential to corroborate (or not) the equivalence of the GM crop with its isogenic non-transgenic counterpart. © 2010 Wiley Periodicals, Inc. Source


Herrero M.,Institute of Industrial Fermentations CSIC | Herrero M.,Autonomous University of Madrid | Simo C.,Institute of Industrial Fermentations CSIC | Garcia-Canas V.,Institute of Industrial Fermentations CSIC | And 2 more authors.
Electrophoresis | Year: 2010

This review article addresses the different chiral capillary electrophoretic methods used to study and characterize foods and beverages through the enantiomeric separation of different food compounds such as amino acids, pesticides, polyphenols, etc. This work intends to provide an updated overview on the main applications of such enantioselective procedures together with their main advantages and drawbacks in food analysis. Some foreseeable applications and developments of these chiral CZE, CEC and MEKC methods for food characterization are also discussed. Papers that were published within the period January 2003 to October 2009 are included, following the previous review on this topic by Simo et al. (Electrophoresis 2003, 24, 2431-2441). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA. Source

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