Laccase modification of the physical properties of bark and pulp of loblolly pine and spruce pulp

Abstract

Pine bark, pine pulp, and spruce pulp were reacted with laccase in the presence of phenolic laccase substrates to modify the fiber surface properties. The acid-base and dispersive characteristics of these modified steam-treated thermomechanical loblolly pine pulps were determined by inverse gas chromatography. Different combinations of substrates with laccase modified the Lewis acid-base characteristics of the pulp. The binding of methylene blue was found unsuitable as an indicator of negative charges on pulps modified by laccase with phenolic substrates; however, its binding did indicate undefined changes in the pulp. Thermomechanical spruce pulp treated with manganese peroxidase or laccase with 4-hydroxyphenylacetic acid increased handsheet strength. Manganese peroxidase treatment also decreased the amount of refining needed to obtain the same freeness, which would indicate potential energy savings. Incremental addition of resorcinol in the presence of laccase altered spruce pulp to a greater extent than did bulk addition. Laccase with substrates also altered the binding of phosphate by modified pine bark.

Citation

Kenealy, William; Klungness, John; Tshabalala, Mandla; Horn, Eric; Akhtar, Masood; Gleisner, Roland; Buschle-Diller, Gisela. 2004. Laccase modification of the physical properties of bark and pulp of loblolly pine and spruce pulp. Lignocellulose biodegradation. Washington, DC : American Chemical Society, 2004. ACS Symposium series ; 889