Functionalization of pectin with laccase-mediated oxidation products of ferulic acid.

Pectin is a natural biopolymer extracted mostly from citrus peel, sugar beet and apple pomace. In order to improve its functional properties and then to enlarge the field of its potential applications, functionalization reaction of citrus pectin with ferulic acid (FA)-oxidation products was performed in aqueous medium, at 30°C and pH7.5, in the presence of Myceliophthora thermophila laccase as biocatalyst. The conjugation between FA-oxidation products and pectin was confirmed using FTIR, UV-Vis and LC-MS analyses. The obtained results suggested that covalent bonds were between the pectin carboxyl groups and FA-oxidation products between the pectin carboxyl groups and FA-oxidation products. The determination of the total phenolic content showed that the modified pectin contained 5 times more phenols than the native pectin. In view of these results, this enzymatic procedure appears as a promising way to provide new pectin-based polymers that are expected to present new properties of interest.