การผลิตเอนไซม์ลิกนินเปอร์ออกซิเดสจากรากกลุ่มไวท์รอทบางชนิด / เบญจวรรณ ยันต์วิเศษภักดี = Production of lignin peroxidase enzyme from some white rot fungi / Benjawan Yanwisetpakdee
Four white rot fungi, Phanerochaete chrysosporium, Ganoderma Iucidum, Ganoderma sp., and Schizophyllum commune, were cultivated in liquid medium containing eucalyptus paper pulp. All tested white rot fungi produced Lignin peroxidase (LiP) at pH4-6, and 30-40 ํC. P. chrysosporium gave the highest LiP activity (0.2956 U/ml.) while Manganese peroxidase (MnP) and Veratryl alcohol oxidase (VAO) were also produced. Ammonium sulfate precipitation (60-80 w/v) gave more higher purification factor than ultra filtration. Increasing in purification factor of LiP and MnP from P. chrysosporium were 5.1 and 4.4 while stabilityt of LiP ans MnP were at pH 5-6, and 35-45 ํC and pH 5-6, and 35-40 ํC, respectively. G. lucidum and Ganoderna sp. produced MnP and Laccase (Lac).After ammonium sulfate precipitation (60-80 w/v), increasing in purification factor of MnP was 4.61 and 4.5 while Lac was 6.2 and 5.06 for G. lucidum and Ganoderma sp., respectively. Stability of MnP and Lac derived from both strains were at pH 4-6 ,and 35 ํC. Increasing in purification factor of MnP derived from S.commune after ammonium sulfate precipitation (60-80 w/v) and stability were 4.69 and pH4-6 and 35 ํC, respectively. Bleaching of eucalyptus paper pulp with LiP derived from P. chrysosporium, MnP derived from S. commune, and Lac derived from G. lucidum and Ganoderma sp.(12.5 IU/gOD) were determined. LiP derived from P. chrysosporium gave the best paper quality with the index numbers of 0.75 for burst index, 5.27 for tear index and 17.03 for tensile index, respectively while MnP derived from S. commune gave the best results on increasing the brightness (4.06%) and decreasing the kappa number(17.46%).