L’imagerie de la micelle de caséine par microscopie à force atomique (AFM)

Milk casein micelles are a natural colloid but it is still unknown their intimate structure. Their structure and stability determine some biological and technological properties of milk such as digestibility or its ability to form yogurt gels or cheese. The atomic force microscopy (AFM) allows to examine the appearance of micelles adsorbed on a solid surface (model for the interface of fat globules), capturing amazing images at the nanometer scale. It was found that the casein micelles are very sensitive to variations in the environmental conditions but also to the adsorption of the particle on a surface such as that used in this study. At a more acid pH, the micelle structure seems less cohesive, due perhaps to the solubilization of a portion of the calcium phosphate

The Use of High Performance Liquid Chromatography for the Characterization of the Unfolding and Aggregation of Dairy Proteins

peer-reviewedHigh-performance liquid chromatography (HPLC) is routinely used to identify and characterize proteins. HPLC can help to understand protein aggregation processes in dairy products, which are induced by common industrial processing steps such as heat treatment. In this chapter, three complementary chromatographic methods are described, which are based on the principles of size exclusion and reversed-phase chromatography. These methods are used to determine the degree of denaturation and aggregation of proteins, and estimate the molecular weight of these aggregates

An oxalate cathode for lithium ion batteries with combined cationic and polyanionic redox

Authors acknowledge financial support from the National Natural Science Foundation of China (51822210), the Australian Research Council (ARC) for its support through Discover Project (DP 140100193),Shenzhen Peacock Plan (KQJSCX20170331161244761), the Program for Guangdong Innovative and Entrepreneurial Teams (No. 2017ZT07C341), and the Development and Reform Commission of Shenzhen Municipality for the development of the “Low-Dimensional Materials and Devices” discipline.The growing demand for advanced lithium-ion batteries calls for the continued development of high-performance positive electrode materials. Polyoxyanion compounds are receiving considerable interest as alternative cathodes to conventional oxides due to their advantages in cost, safety and environmental friendliness. However, polyanionic cathodes reported so far rely heavily upon transition-metal redox reactions for lithium transfer. Here we show a polyanionic insertion material, Li2Fe(C2O4)2, in which in addition to iron redox activity, the oxalate group itself also shows redox behavior enabling reversible charge/discharge and high capacity without gas evolution. The current study gives oxalate a role as a family of cathode materials and suggests a direction for the identification and design of electrode materials with polyanionic frameworks.Publisher PDFPeer reviewe

Scientific mission to Rennes and Nantes

vokBEL/UT

β-lactoglobulin as a molecular carrier of linoleate: characterisation and effects on intestinal epithelial cells in vitro

S. Le Maux is currently supported by a Teagasc Walsh Fellowship and the Department of Agriculture, Fisheries and Food (FIRM project 08/RD/TMFRC/650). We also acknowledge funding from IRCSET-Ulysses Travel Grant.peer-reviewedThe dairy protein β-lactoglobulin (βlg) is known to bind hydrophobic ligands such as fatty acids. In the present work, we investigated the biological activity in vitro of linoleate once complexed to bovine βlg. Binding of linoleate (C18:2) to bovine βlg was achieved by heating at 60 °C for 30 min at pH 7.4, resulting in a linoleate/βlg molar binding stoichiometry of 1.1, 2.1, and 3.4. Two types of binding sites were determined by ITC titrations. Binding of linoleate induced the formation of covalent dimers and trimers of βlg. The LD50 on Caco-2 cells after 24 h was 58 μM linoleate. However, cell viability was unaffected when 200 μM linoleate was presented to the Caco-2 cells as part of the βlg complex. The Caco-2 cells did not increase mRNA transcript levels of long chain fatty acid transport genes, FATP4 and FABPpm, or increase levels of the cAMP signal, in response to the presence of 50 μM linoleate alone or as part of the βlg complex. Therefore, it is proposed that βlg can act as a molecular carrier and alter the bioaccessibility of linoleate/linoleic acid