Semi-quantitative purification and assessment of purity of three soybean proteins - glycin, B-conglycinin and A-conglycinin- by SDS-PAGE electrophoresis, densitometry and immunoblotting

International audienc

Allergic reactions to hydrolysed wheat proteins: clinical aspects and molecular structures of the allergens involved

International audienceWheat gluten can be chemically or enzymatically hydrolysed to produce functional ingredients useful in food and cosmetics. However severe allergies to hydrolysed wheat proteins (HWP) have been described in Europe and Japan since the early 2000's. Triggering proteins and IgE epitopes were described both for French and Japanese cohorts and appeared remarkably similar leading to define a new wheat allergic entity. Deamidation induced by functionalisation generate neo-allergens responsible for this particular allergy. This article aims to review the processes leading to deamidation and the clinical features of the patients suffering from this allergy. Then the molecular determinants involved in HWP-allergy were exhaustively described and hypothesis regarding the sensitizing mechanism of HWP-allergy are discussed. Finally, current regulation and tools aiming at managing this risk associated with HWP are presented

Emulsifying properties of acylated rapeseed (Brassica napus L.) peptides

International audienc

Modifications des propriétés fonctionnelles des protéines par voie enzymatique

National audienc

Les enzymes, nouveaux outils ? Nouveaux procédés, Nouveaux produits ?

National audienc

Améliorer l’évaluation de l’allergénicité de nouvelles protéines alimentaires : quels outils pour le futur ?

De nouveaux ingrédients protéiques vont être mis sur le marché et nécessiteront une évaluation du risque d’allergie alimentaire. L’article mentionne les limites des méthodes actuelles pour prédire ce risque et présente des méthodes in vitro et des modèles cellulaires en cours de développement choisis sur la base des étapes clés de l’allergie. Une approche pertinente doit prendre en compte à la fois la propriété des protéines à déclencher des réactions allergiques chez les personnes déjà allergiques mais aussi et surtout la capacité à sensibiliser de novo des individus. Les allergènes alimentaires possèdent des caractéristiques structurales particulières et une stabilité vis-à-vis de la digestion. Cependant, ces paramètres ne permettent pas de prédire le risque. Le potentiel allergène d’une protéine repose aussi sur sa capacité à franchir l’épithélium intestinal sous une forme immunologiquement active et à activer des cellules de l’immunité innée et spécifique.New protein ingredients will be placed on the market and will require evaluating the risk of food allergy. The paper mentions the limitations of current methods of allergic risk assessment and presents in vitro methods and cell models being developed based on the key steps of allergy. A relevant approach must take into account the property of proteins to trigger allergic reactions in people already allergic but also most particularly, their ability to de novo sensitize individuals. Food allergens possess particular structural features and a resistance to digestive enzymes. However, these parameters are not sufficient for risk prediction. The allergen potential of a protein also depends on its capacity to cross the intestinal epithelium in an immunologically active form and to activate cells from innate and adaptive immunity

Des surfactants « verts » préparés à partir de fractions protéiques industrielles de colza

Edible surfactants were prepared from rapeseed meal by functionalization of two types of products: proteins or peptide fractions obtained by enzymatical hydrolysis. Functionalization aimed to enhance the amphophilic characteristics of the products by grafting hydrophobic chains\; it was based on acylation or sulfamidation of proteins and acylation of peptides. The interfacial properties of these “green” surfactants measured by lowering the surface tension, and increasing the stability of foams and emulsions, were improved, depending on the chemical reagent used. For example, peptides modified by C1 4 acyl chlorides exhibited the better emulsifying properties, whereas the better foaming properties were obtained with peptides modified by C 10 and C 12 acyl chlorides. These surfactants could diversify the uses of rapeseed derivatives, particularly in non food industries

Fonctionnalisation de protéines végétales par les transglutaminases

National audienc