Study on identification of white rot fungi CP29 and its laccase biosynthesis
Keywords:Perenniporia tephropora, cultivation condition, identification, ITS-rDNA, laccase.
White-rot fungi are the most efficiency degrader of wood lignin by having extracellular ligninolyitc enzymes system; lignin peroxidases, manganese peroxidases and laccase. Laccase has an important role in ligninolysis and has been widely applied in some industries. The fungus CP29, which showed high laccase activity, was indentified and chosen for laccase biosynthesis. The fruiting bodies of strain CP29 formed an effused, very flat, yellow green hymenium layer. The colony was off-white and uniformly circular. The mycelia were thick and closely bound together. Beside ligninase, this fungus could produce other extracellular enzymes such as protease, cellulase and amylase. Biological characteristics of strain CP29 suggest that it belongs to the subdivision Basidiomycota. Based on morphological characteristics and ITS-rDNA region analysis, the strain CP29 was classified as Perenniporia tephropora. The ITS–rDNA gene sequence of of P. tephropora CP29 was deposited into GenBank (NCBI) under the accession number KX257798. To enhance laccase production, optimal cultivation conditions were investigated. This strain P. tephropora CP29 showed the highest laccase activity, reaching 7669.05 U/L on MT1 medium containing 0.0625mM CuSO4 after 7 days of cultivation at 37°C and pH 5.0.