Lipophilisation de composés phénoliques par voie enzymatique et propriétés antioxydantes des molécules lipophilisées

The oxidative modification of lipids in foods and cosmetics may lead to alteration of their qualities and can have physiopathological repercussion on consumer. To counteract these inauspicious effects, phenolic compounds, derived from plants, such as phenolic acids and flavonoids seem to be particularly promising. However, their relatively low solubility in apolar media limits their application in oil-based products. In emulsion, thanks to their water-solubility, these compounds are located in aqueous compartment, whereas lipid peroxidation occurs at the oil-water interface. Therefore, there is an interest in trying to enhance the amphiphilic character of phenolic antioxidants by enzymatic lipophilization which corresponds to the grafting of an aliphatic chain (fatty alcohol, acid or amine) through lipase-catalysed esterification or amidation reactions. Due to its amphiphilic nature, the resulting functionalized antioxidant would accumulate at the oil-water interface, increasing protection of target-lipids from oxidation. Various operational conditions and strategies can be adopted to perform lipase-mediated hydrophobation with high yields. This paper firstly presents a panorama of the advances in this field. Finally, the antioxidant capacity of lipophilized compounds is reviewed and compared with that of the native molecule.