Combination of laccase, xylanase and cellulase in lignocellulose degradation by white rot fungi, Lentinus polychrous Lev. and L. squarrosulus Mont

• Published in: Witthayāsān Kasētsārt. Sākhā thammācht
• Main Authors: Charida Pukahuta(Ubon Rajathanee University, Ubon Ratchathani (Thailand). Faculty of Science. Department of Biological Sciences), Poonpilai Suwanarit(Kasetsart University. Bangkhen Campus, Bangkok (Thailand). Faculty of Science. Department of Microbiology), Shianagawa, Emiko(Ube National College of Technology, Yamaguchi (Japan)), Hoshida, Hisashi(Yamaguchi University, Ube (Japan). Faculty of Engineering. Dept. of Applied Chemistry and Chemical Engineering), Nishizawa, Yoshinori(Yamaguchi University, Ube (Japan). Faculty of Engineering. Dept. of Applied Chemistry and Chemical Engineering)
• Format: Journal Article
• Language: English
• Published: 01.01.2004
• Subjects: Cellulase; Degradation; Enzymes; Fungi; Laccase; Lentinus; Lentinus polychrous; Lentinus squarrosulus; Lignocellulose; white rot fungi; xylanase
• ISSN: 0075-5192

22 isolates of white rot fungi, Lentinus spp. were screened for their activity of cellulase, xylanase and laccase. L. polychrous Lev. LP-PT-1 was cultured in 8 liquid media and 2 solid media. These 10 media were tested for lignocellulose degradation. Potato dextrose broth (PDB) and Fahraeus broth with 2 percent rice straw (FRS) were selected as appropriate media. Both media were conducted to cultivate 4 isolates of L. polychrous Lev. LP-PT-1, LP-SW-3, LP-WR-13 and LP-UD-1 and 1 isolate of L. squarrosulus Mont.LS-YA. The xylanase and cellulase activities were determined at 40 deg C. Xylidine induced higher laccase actvity in 4 isolates, with the exception of LP-PT-1. LP-PT-1 produced three enzyme actvities in both PDB and FRS with and without xylidine addition. LP-SW-3 produced the highest activity of xylanase and laccase, 13.1 mU/ml and 3.27 U/ml, respectively, in FRS with xylidine addition. LP-SW-3, LP-WR-13 and LP-UD-1 showed the activity of three enzymes in FRS but lacked cellulase and/or xylanase activities in PDB. The production of xylanase of LP-SW-3 in FRS was induced by rice straw and of LP-UD-1 in PDB was induced by xylidine. LS-YA had the activity of all three enzymes in PDB but lacked xylanase activity in FRS without xylidine addition. FRS and xylidine addition was used to produce the culture broth for bleaching pulp. The increase in brightness of the treated pulp, 1.5-2.0 percent higher than the control pulp, was correlated with the detected activity of xylanase of L. polychrous Lev.LP-PT-1, LP-UD-1 and L. squarrosulus Mont.LS-YA with low activity of laccase in each isolate. The high and moderate activity of xylanase with high and moderate activity of laccase in L. polychrous Lev. LP-SW-3 and LP-WR-13 did not increase the brightness of the treated pulp. It was concluded that these thermotolerant white rot fungi have the different combination of enzyme systems on lignocellulose degradation. The bleaching of pulp beneficially effected by the xylanase activity only when the activity of laccase was low.