title: Identification of proteins from wild cardoon flowers (Cynara cardunculus L.) by a proteomic approach.
abstract: Proteomic approach was applied to identify total proteins, particularly the enzymatic content, from wild cardoon flowers. As the selection of an appropriate sample preparation method is the key for getting reliable results, two different extraction/precipitation methods (trichloroacetic acid and phenol/ammonium acetate) were tested on fresh and lyophilized flowers. After two-dimensional electrophoresis (2D-E) separations, a better protein pattern was obtained after phenol extraction from lyophilized flowers. Only 46 % of the total analyzed spots resulted in a protein identification by mass spectrometry MALDI-TOF. Four proteases (cardosins A, E, G, and H), which have become a subject of great interest in dairy technology, were identified. They presented molecular weights and isoelectric points very close and high levels of homology between matched peptides sequences. The absence of the other cardosins (B, C, D, and F) could be an advantage, as it reduces the excessive proteolytic activity that causes bitter flavors and texture defects, during cheese making.
authors.affiliation: University of Liège, Gembloux Agro-Bio tech, Laboratory of Food Science and Formulation, Passage des Déportés 2, B-5030 Gembloux, Belgium ; University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP, W-3038 Sfax, Tunisia.
authors.forename: Amal
authors.initials: A
authors.lastname: Ben Amira
authors.affiliation: University of Liège, Gembloux Agro-Biotech, Laboratory of Functional and Evolutionary Entomology, Passage des Déportés 2, B-5030 Gembloux, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: Bauwens
authors.affiliation: University of Liège, Mass Spectrometry Laboratory, B6 Building, 4000 Liège, Belgium.
authors.forename: Edwin
authors.initials: E
authors.lastname: De Pauw
authors.affiliation: University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP, W-3038 Sfax, Tunisia.
authors.forename: Souhail
authors.initials: S
authors.lastname: Besbes
authors.affiliation: University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP, W-3038 Sfax, Tunisia.
authors.forename: Hamadi
authors.initials: H
authors.lastname: Attia
authors.affiliation: University of Liège, Gembloux Agro-Biotech, Laboratory of Functional and Evolutionary Entomology, Passage des Déportés 2, B-5030 Gembloux, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Francis
authors.affiliation: University of Liège, Gembloux Agro-Bio tech, Laboratory of Food Science and Formulation, Passage des Déportés 2, B-5030 Gembloux, Belgium.
authors.forename: Christophe
authors.initials: C
authors.lastname: Blecker
keywords: 2D gel electrophoresis; Cardosin; MALDI-TOF MS; Protein extraction; Proteomic; Wild cardoon