title: Laccase catalyzed covalent coupling of fluorophenols increases lignocellulose surface hydrophobicity.
abstract: This work presents for the first time the mechanistic evidence of a laccase-catalyzed method of covalently grafting hydrophobicity enhancing fluorophenols onto Fagus sylvatica veneers. Coupling of fluorophenols onto complex lignin model compounds guaiacylglycerol beta-guaiacyl ether and syringylglycerol beta-guaiacyl ether was demonstrated by LC-MS and NMR. Laccase-mediated coupling increased binding of 4-[4-(trifluoromethyl)phenoxy]phenol (4,4-F3MPP) and 4-(trifluoromethoxy)phenol (4-F3MP) to veneers by 77.1% and 39.2%, respectively. XPS studies showed that laccase-catalyzed grafting of fluorophenols resulted in a fluorine content of 6.39% for 4,4-F3MPP, 3.01% for 4-F3MP and 0.26% for 4-fluoro-2-methylphenol (4,2-FMP). Grafting of the fluorophenols 4,2-FMP, 4-F3MP and 4,4-F3MPP led to a 9.6%, 28.6% and 65.5% increase in hydrophobicity, respectively, when compared to treatments with the respective fluorophenols in the absence of laccase, in good agreement with XPS data.
authors.affiliation: Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12, A-8010 Graz, Austria.
authors.forename: Tukayi
authors.initials: T
authors.lastname: Kudanga
authors.forename: Endry Nugroho
authors.initials: EN
authors.lastname: Prasetyo
authors.forename: Petri
authors.initials: P
authors.lastname: Widsten
authors.forename: Andreas
authors.initials: A
authors.lastname: Kandelbauer
authors.forename: Sandra
authors.initials: S
authors.lastname: Jury
authors.forename: Carol
authors.initials: C
authors.lastname: Heathcote
authors.forename: Jussi
authors.initials: J
authors.lastname: Sipilä
authors.forename: Hansjoerg
authors.initials: H
authors.lastname: Weber
authors.forename: Gibson S
authors.initials: GS
authors.lastname: Nyanhongo
authors.forename: Georg M
authors.initials: GM
authors.lastname: Guebitz
mesh_terms: D002851:Chromatography, High Pressure Liquid; D029964:Fagus / Q000737:chemistry*; D006140:Guaifenesin / Q000031:analogs & derivatives* / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D042845:Laccase / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D010636:Phenols / Q000378:metabolism*; D056951:Photoelectron Spectroscopy; D013499:Surface Properties; D014934:Wood / Q000378:metabolism*
chemical_list: D010636:Phenols; C036909:lignocellulose; D006140:Guaifenesin; C046052:guaiacylglycerol-beta-guaiacyl ether; D008031:Lignin; D042845:Laccase