Full Length Research Paper

Polycyclic aromatic hydrocarbons (PAHs) degradation by laccase from a tropical white rot fungus Ganoderma lucidum

Hunsa Punnapayak¹*, Sehanat Prasongsuk¹, Kurt Messner³, Khanchai Danmek^1,2 and Pongtharin Lotrakul¹

¹Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.

²Biotechnology Program, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.

³Abteilung Mykologie, Institut für Biochemische Technologie and Mikrobiologie, Technische Universität Wien, A-1060 Vienna, Austria.

*Corresponding author. E-mail: phunsa@chula.ac.th. 

Accepted 28 September, 2009

   Abstract

Laccase enzyme was produced from an isolate of the white rot fungus, Ganoderma lucidum Chaaim-001 BCU. The enzyme was subsequently evaluated for its degradative ability towards sixteen types of polycyclic aromatic hydrocarbons (PAHs). The G. lucidum laccase degraded antracene completely with or without a redox mediator (2 mM 1-hydroxybenzotriazole) and also degraded benzo[a]pyrene, fluorine, acenapthene, acenaphthylene and benzo[a]anthracene up to 100.0, 98.6, 95.4, 90.1 and 85.3 %, respectively, when the mediator was present. In the absence of the mediator, the ability to degrade these compounds dropped to 71.71, 62.9, 80.49, 85.85 and 9.14% respectively. Compared to the laccase enzyme from Trametes vesicolor, G. lucidum laccase appeared to retain more of its capability to degrade these PAHs when the mediator was absent.  

Key words: Laccase, Ganoderma lucidum, polycyclic aromatic hydrocarbons.