Ton X.-A.,Compiègne University of Technology |
Acha V.,Polytechnic Institute of LaSalle Beauvais |
Haupt K.,Compiègne University of Technology |
Tse Sum Bui B.,Compiègne University of Technology
Biosensors and Bioelectronics | Year: 2012
A rapid, robust, sensitive and economic sensing method, based on a molecularly imprinted polymer (MIP) synthetic antibody mimic, and fluorescence polarization analysis, for the direct detection of UV-excited fluorescent analytes in food and environmental samples was developed. Fluoroquinolone (FQ) antibiotics were used as fluorescent model analytes. Water-compatible MIP nanoparticles were synthesized with enrofloxacin (ENRO) as the imprinting template. Fluorescence polarization measurements then allow the direct determination of the amount of ENRO and other structurally related piperazine-based fluoroquinolones that bind to the MIP. No separation step was required since this technique distinguishes in situ analyte molecules bound to the MIP from the free analyte in solution. This assay was successfully applied for the first time to determine FQs in real samples, i.e. tap water and milk, without any prior concentration step, by simply adding a known amount of MIP. No interference by the sample components was observed even though the excitation was in the UV region. In tap water, a low limit of detection of 0.1nM for ENRO was achieved with 5μgmL -1 of MIP. In milk, ENRO and danofloxacin, whose MRLs have been fixed at 0.28μM and 0.08μM, respectively, could be selectively measured and distinguished from other families of antibiotics. The procedure is very easy and practical as it consists of simply precipitating the milk proteins with acetonitrile and adding buffer and MIP to the supernatant before reading the polarization values with a spectrofluorimeter. © 2012 Elsevier B.V.
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: KBBE-2009-2-5-02 | Award Amount: 3.65M | Year: 2010
Strategic network learning is of crucial importance for innovation as it enables the food company to expand its resource base and to absorb new trends and technologies. It is observed that food SMEs often fail in establishing a strategic and efficient network. This project sheds new light on this issue by combining research actions at two levels: the focal company level, investigating how attitudes and preferences determine the food SMEs individual network behaviour in order to achieve business objectives. The network level, investigating the functioning of the network as a whole and how this results in innovation and economic growth and how network stakeholders can make the network better performing. The project combines scientific research with developing network learning tools of practical use to food SMEs, network organisations and policy makers. A broad definition of networks is applied, including networking with competitors, suppliers, knowledge centres and a variety of other actors through formal and informal linkages. Research activities take three steps: (1) profound analysis of success factors and barriers for network learning. Particular focus is on the relationship between informal and formal networking and global networks. (2) Network behaviour is analysed at the focal company level, providing insight in network characteristics affecting innovation and SMEs preferences for different network designs. (3) a prototype tool is developed and tested to assess performance of the network at network level. In the development stage of the project, the network learning toolbox will be developed, market-tested and launched. It consists of a set of instruments to enhance the capacity of SMEs, network organizations and policy makers to improve network learning based on strategic network management. The strength of the toolbox lies in the confrontation of our instruments with the business perspective and two-stage testing within SMEs and network organizations.
Pourret O.,Polytechnic Institute of LaSalle Beauvais |
Davranche M.,French National Center for Scientific Research
Journal of Colloid and Interface Science | Year: 2013
Manganese oxides are important scavengers of rare earth elements (REE) in hydrosystems. However, it has been difficult to include Mn oxides in speciation models due to the lack of a comprehensive set of sorption reactions consistent with a given surface complexation model (SCM), as well as discrepancies between published sorption data and predictions using the available models. Surface complexation reactions for hydrous Mn oxide were described using a two surface site model and the diffuse double layer SCM. The specific surface area, surface side density, and pHzpc were fixed to 746m2/g, 2.1mmol/g, and 2.2, respectively. Two site types (XOH and YOH) were also used with pKa2 values of 2.35 (XOH) and 6.06 (YOH). The fraction of the high affinity sites was fixed at 0.36. Published REE sorption data were subsequently used to determine the equilibrium surface complexation constants, while considering the influence of pH, ionic strength, and metal loading. LogK increases from light REE to heavy REE and, more specifically, displays a convex tetrad effect. At low metal loading, the YOH site type strongly expresses its affinity toward REE, whereas at higher metal loading, the same is true for the XOH site type. This study thus provides evidence for heterogeneity in the distribution of the Mn oxide binding sites among REE. © 2012 Elsevier Inc.
Tessier F.J.,Polytechnic Institute of LaSalle Beauvais |
Birlouez-Aragon I.,Spectralys Innovation
Amino Acids | Year: 2012
In food science the Maillard reaction is well known to cause degradation of amino acids and an overall decrease in the nutritional value of foods that have been subjected to heat in processing. There has been evidence more recently of the endogenous formation of some Maillard reaction products (MRPs) in biological systems and their association with pathophysiological conditions including diabetes, renal disease and cardiovascular disease. Several studies have suggested that dietary MRPs increase the in vivo pool of MRPs after intestinal absorption and contribute to the development of diabetes and related complications. This review focuses on the animal and human studies which have assessed the eventual implications of dietary MRPs on human health, highlighting the different diets tested, the experimental designs and the biomarkers selected to estimate the health effects. The results of these studies are compared to those of the recently published ICARE study. In this latter study an accurate determination of the MRP content of the diets was achieved, allowing the calculation of the contribution of individual food groups to daily MRP intakes in a regular western diet. © Springer-Verlag 2010.
Houben D.,Catholic University of Louvain |
Houben D.,Polytechnic Institute of LaSalle Beauvais |
Evrard L.,Catholic University of Louvain |
Sonnet P.,Catholic University of Louvain
Biomass and Bioenergy | Year: 2013
Phytoremediation of soils contaminated by heavy metals was tested by liming (CaCO3) or adding biochar (1%, 5% and 10%, mass fraction) and by growing rapeseed (Brassica napus L.), a common bioenergy crop. Bioavailable metal concentrations (0.01molL-1 CaCl2 extraction) decreased with increasing concentrations of biochar amendment. The reduction reached 71%, 87% and 92% for Cd, Zn and Pb respectively in the presence of 10% biochar. Twelve weeks after sowing, all plants cultivated on the untreated soil and on the soil amended by biochar at 1% had died, while the plants grew normally on the soil that had the other treatments. Compared to liming, treatment with 10% biochar proved equally efficient in reducing metal concentrations in shoots but the biomass production tripled as a result of the soil fertility improvement. Thus, in addition to C sequestration, the incorporation of biochar into metal-contaminated soils could make it possible to cultivate bioenergy crops without encroaching on agricultural lands. Although additional investigations are needed, we suggest that the harvested biomass might in turn be used as feedstock for pyrolysis to produce both bioenergy and new biochar, which could contribute further to the reduction of CO2 emission. © 2013 Elsevier Ltd.
Roman M.,CNR Institute of Neuroscience |
Jitaru P.,Polytechnic Institute of LaSalle Beauvais |
Barbante C.,CNR Institute of Neuroscience
Metallomics | Year: 2014
Despite its very low level in humans, selenium plays an important and unique role among the (semi)metal trace essential elements because it is the only one for which incorporation into proteins is genetically encoded, as the constitutive part of the 21st amino acid, selenocysteine. Twenty-five selenoproteins have been identified so far in the human proteome. The biological functions of some of them are still unknown, whereas for others there is evidence for a role in antioxidant defence, redox state regulation and a wide variety of specific metabolic pathways. In relation to these functions, the selenoproteins emerged in recent years as possible biomarkers of several diseases such as diabetes and several forms of cancer. Comprehension of the selenium biochemical pathways under normal physiological conditions is therefore an important requisite to elucidate its preventing/therapeutic effect for human diseases. This review summarizes the most recent findings on the biochemistry of active selenium species in humans, and addresses the latest evidence on the link between selenium intake, selenoproteins functionality and beneficial health effects. Primary emphasis is given to the interpretation of biochemical mechanisms rather than epidemiological/observational data. In this context, the review includes the following sections: (1) brief introduction; (2) general nutritional aspects of selenium; (3) global view of selenium metabolic routes; (4) detailed characterization of all human selenoproteins; (5) detailed discussion of the relation between selenoproteins and a variety of human diseases. © 2014 The Royal Society of Chemistry.
Niquet-Leridon C.,Polytechnic Institute of LaSalle Beauvais |
Tessier F.J.,Polytechnic Institute of LaSalle Beauvais
Food Chemistry | Year: 2011
Nε-carboxymethyl-lysine (CML) is considered to be an important marker of the Maillard reaction. In the present investigation a liquid chromatography coupled to ion trap tandem mass spectrometry has been developed for the analysis of CML and lysine in drink mixes. To ensure the best specificity of the method, porous graphitic carbon packing material was used for the chromatographic separation and two transition reactions were recorded per analyte. With the stable-isotope dilution technique employed in this method the recovery ranged from 100% to 111.4% for CML. All other performance characteristics tested were also satisfactory. The method was applied to the analysis of chocolate-flavoured drink mixes after sodium borohydride reduction and acid hydrolysis. In this food category, CML content varied from 8.1 to 131.9 μg/g powder or 95 to 3527 μg/g protein. Among the food items analysed by different laboratories chocolate-flavoured drink mixes appear to have one of the highest CML contents. © 2010 Elsevier Ltd. All rights reserved.
Chango A.,Polytechnic Institute of LaSalle Beauvais |
Abdennebi-Najar L.,Polytechnic Institute of LaSalle Beauvais
Nutrition Reviews | Year: 2011
Malaria induced by Plasmodium falciparum is a major cause of mortality. P. falciparum has the ability to use host plasma folate as its primary folate source. Folate is a cofactor needed for both malaria parasite growth and host erythrocyte production. This review examines the possible impairment of the folate-mediated one-carbon metabolism pathway as a result of P. falciparum malaria infection during pregnancy. Folate deficiency during malaria infection is presented, with an emphasis on the controversy regarding the decrease of plasma or erythrocyte folate secondary to malaria. Maternal folate deficiency increases the risk of adverse pregnancy outcomes. Functional folate deficiency and/or increased plasma homocysteine levels during pregnancy of infected women in areas endemic for malaria is a probable scenario accentuating the impairment of placenta function leading to the occurrence of neural tube defects, low birth weights, and intrauterine growth retardations. Potential questions that may be answered in future investigations using an appropriate protocol to study pregnant women with malaria are also addressed. © 2011 International Life Sciences Institute.
Sorba A.,Polytechnic Institute of LaSalle Beauvais |
Sopade P.A.,University of Queensland
Starch/Staerke | Year: 2013
Changes in the rapid visco-analysis (RVA) viscosity of potato and waxy maize starches during digestion were studied using amyloglucosidase and α-amylase (60-1700 U/mL), and three solids contents (3-20%) of the starch dispersions in a replicated randomised experiment. The starches were gelatinised in the RVA before digestion at 50°C at a shear rate of 17 s-1 for 5 min. Control dispersions effectively did not change (<10%) in viscosity with time. With the enzyme-treated gels, irrespective of the starch, enzyme or concentration, the RVA viscosity reduced with time as low molecular weight (MW) products were produced. A modified first-order kinetic model suitably described (r2>0.9) the starch viscosity-digestograms. The rate of change in starch viscosity, KVIS (an index of the rate of starch digestion), was significantly (p<0.05) inversely related to the solids content, and directly related to the enzyme concentration. KVIS of the waxy maize starch was higher than that of the potato starch, and a higher KVIS was measured with the α-amylase than with the amyloglucosidase. Differences in potato and waxy maize starch structures, specificity of enzymes and enzyme:substrate ratios can explain the results, and rheology is proposed as valuable in starch digestion. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The Maillard reaction in the human body. The main discoveries and factors that affect glycation [La réaction de Maillard dans le corps humain. Découvertes majeures et facteurs qui affectent la glycation]
Tessier F.J.,Polytechnic Institute of LaSalle Beauvais
Pathologie Biologie | Year: 2010
Ever since the discovery of the Maillard reaction in 1912 and the discovery of the interaction between advanced glycation end-products and cellular receptors, impressive progress has been made in the knowledge of nonenzymatic browning of proteins in vivo. This reaction which leads to the accumulation of random damage in extracellular proteins is known to have deleterious effects on biological function, and is associated with aging and complication in chronic diseases. Despite a controlled membrane permeability and a protective regulation of the cells, intracellular proteins are also altered by the Maillard reaction. Two main factors, protein turnover and the concentration of carbonyls, are involved in the rate of formation of the Maillard products. This paper reviews the key milestones of the discovery of the Maillard reaction in vivo, better known as glycation, and the factors which are likely to affect it. © 2009 Elsevier Masson SAS.