|Title||Enzymatic modification of different lignins through oxidative coupling with hydrophilic compounds|
|Author(s)||Fiţigəu, Ionita Firuta; Boeriu, Carmen Gabriela; Peter, Francisc|
|Source||Macromolecular Symposia 352 (2015)1. - ISSN 1022-1360 - p. 78 - 86.|
FBR Sustainable Chemistry & Technology
|Publication type||Refereed Article in a scientific journal|
|Keyword(s)||grafting - laccase - lignin - oxidative coupling|
The enzymatic oxidative coupling of five technical lignins from different sources and with different molecular properties, with glucosamine and the tripeptide glycil-tyrosyl-glycine was studied in acetone/water mixture, using laccase as catalyst. The modified lignin was isolated and the product was characterized by means of size exclusion chromatography, FT-IR and 31P-NMR, in order to evidence the main lignin modifications after laccase coupling reactions. An important increase of the molecular weight and significant structural modifications were observed for the product obtained after the coupling reactions of Organosolv Hardwood Lignin and Alkali pretreated Wheat straw Lignin with glucosamine and glycil-tyrosyl-glycine, demonstrating the achievement of the modification reactions.