Screening and identification of Trametes lactinea and Pycnoporouscoccineus isolated from Kampar for laccase production

ABSTRACT

Aims: Laccase is a blue copper oxidase that catalyses four electron reduction of molecular oxygen to water. It is able to oxidise aromatic compounds with molecular oxygen as the terminal electron acceptor. The aim of this study was to screen for laccase producing basidiomycetes isolated from decaying woods and tree trunks around Kampar, Perak. Methodology and results: The isolated basidiomycetes were screened for their laccase activity on different agar plates supplemented with 2, 2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), guaiacol and Remazol Brillant Blue R (RBBR), respectively. In the presence of laccase, the colourless ABTS and guaiacol were oxidised to form blue-green and reddish-brown coloured zone around the fungal colony, respectively; whereas the blue RBBR was decolourised by the enzyme. Colour or colourless halo zones that are formed on the agar plates indicate the presence of ligninolytic enzyme activities. Isolates KA1 and TR9 indicated the highest enzymatic hydrolysis on ABTS plates with the halo zone ratio of 1.43  0.04 and 0.98  0.01, respectively. Based on the BLAST results from the amplicon of ITS1 and ITS4 primers, Isolates KA1 and TR9 were identified as Trametes lactinea and Pycnoporous coccineus, respectively. Under submerged fermentation, P. coccineus has higher laccase production (0.72 U/mL) compared with T. lactinea (0.16 U/mL). Conclusion, significance and impact of study Both T. lactinea and P. coccineus are potential strains for laccase production which can be used for dye decolourisation and degradation. Future studies will focus on the application of the laccase in textile dye degradation.