Behaviors of bovine serum albumin and rapeseed proteins at the air/water interface after grafting aliphatic or aromatic chains.
The influence of grafting aliphatic or aromatic groups on the behaviors of bovine serum albumin (BSA) and rapeseed proteins (napin and cruciferin) at the air/water interface is studied. From compression isotherms, it is shown that the chemical modification induces an increase in the interfacial molecular areas of the three proteins. The more hydrophobic the groups grafted, the more important this increase is. The dilatational modulus clearly emphasized that the grafting of hydrophobic groups also leads to an increase of the collapse pressure, demonstrating a higher cohesiveness and resistance to pressure of the interfacial films. These results are discussed on the basis of the physicochemical changes due to these chemical modifications, especially the conformation, the surface hydrophobicity, and the flexibility of the modified proteins. The improvement of surface properties obtained by grafting aliphatic or aromatic chains onto these proteins looks very promising in regard to emulsifying and foaming properties.
Gerbanowski
Alice
A
Institut National de Recherche Agronomique, Unité de Recherche sur les Protéines Végétales et leurs Interactions, BP 71627, 44316 Nantes cedex 03, France.
Rabiller
Claude
C
Guéguen
Jacques
J
D000215:Acylation; D000388:Air; D000473:Alkanes; D000818:Animals; D029741:Brassica rapa / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic; D010940:Plant Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water
D000473:Alkanes; D006841:Hydrocarbons, Aromatic; D010940:Plant Proteins; D013501:Surface-Active Agents; D014867:Water; D012710:Serum Albumin, Bovine