title: Towards industrially-feasible delignification and pitch removal by treating paper pulp with Myceliophthora thermophila laccase and a phenolic mediator.
abstract: The ability of two natural phenols to act as mediators of the recombinant Myceliophthora thermophila laccase (MtL) in eucalypt-pulp delignification was investigated. After alkaline peroxide extraction, the properties of the enzymatically-treated pulps improved with respect to the control. The pulp brightness increased (3.1 points) after the enzymatic treatment with MtL alone, but the highest improvements were obtained after the MtL treatment using syringaldehyde (4.7 points) and especially methyl syringate (8.3 points) as mediators. Likewise, a decrease in kappa number up to 2.7 points was obtained after the MtL-methyl syringate treatment, followed by decreases of 1.4 and 0.9 points after the treatments with MtL-syringaldehyde and MtL alone, respectively. On the other hand, removal of the main lipophilic extractives present in eucalypt pulp was observed after the above laccase-mediator treatments. Finally, the doses of both MtL and methyl syringate were reduced, and results compatible with industrial implementation were obtained.
authors.affiliation: Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC, P.O. Box 1052, E-41080 Seville, Spain.
authors.forename: Esteban D
authors.initials: ED
authors.lastname: Babot
authors.forename: Alejandro
authors.initials: A
authors.lastname: Rico
authors.forename: Jorge
authors.initials: J
authors.lastname: Rencoret
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Kalum
authors.forename: Henrik
authors.initials: H
authors.lastname: Lund
authors.forename: Javier
authors.initials: J
authors.lastname: Romero
authors.forename: José C
authors.initials: JC
authors.lastname: del Río
authors.forename: Angel T
authors.initials: AT
authors.lastname: Martínez
authors.forename: Ana
authors.initials: A
authors.lastname: Gutiérrez
mesh_terms: D001547:Benzaldehydes / Q000378:metabolism; D019149:Bioreactors; D005052:Eucalyptus / Q000737:chemistry; D005707:Gallic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D042845:Laccase / Q000378:metabolism*; D008031:Lignin / Q000032:analysis / Q000378:metabolism*; D010209:Paper; D011136:Polysorbates; D020037:Sordariales / Q000201:enzymology*; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D001547:Benzaldehydes; D011136:Polysorbates; C506133:methyl syringate; C069665:syringaldehyde; D005707:Gallic Acid; D008031:Lignin; D042845:Laccase