Characterization of Lignin Peroxidase from Paecilomyces Species for Decolorisation of Pulp and Paper Mill Effluent

摘要

Native fungal isolates F1 - F8 and control fungi Phanerochaete chrysosporium were capable of degrading pulp and paper industry effluent and also efficient producers of cellulolytic and lignolytic enzymes. F3 (Paecilomyces sp) strain showed higher enzyme activity as compared to other native fungal isolates. Weight loss, cellulose loss and organic carbon contents were found maximum in F3. Reducing sugar, protein content and colour removing potential was also higher in F3. Color reduction initiated very fast with microbial enzyme treatment (initiated only after 2h of incubation) and reached maximum reduction after 24h. Lignin peroxidase fraction Ⅰ and Ⅱ resulted in 53% and 34% removal of colour and 36% and 38% lignin removal. The culture extract of F3 strain grown on pulp and paper effluent consists of five protein fractions and out of them two fractions of 38 and 40 kDa molecular weight showed lignin peroxidase activity. The pH and temperature optimum for lignin peroxidase activity were 2 to 3, and 20 - 30 ℃, respectively. Maximum activity was observed at 6 mM to 48 mM veratryl alcohol concentration and 256 mM H_2O_2, however, sodium azide inhibits the enzyme activity. Different metals (CoCl_2, HgSO_4, CaCl_2, SnCl_2, FeSO_4, CuSO_4 and ZnSO_4) also affected the lignin peroxidase activity.