Degradation of Polycyclic Aromatic Hydrocarbons by Rigidoporus lignosus and its Laccase in the Presence of Redox Mediators
The metabolism of polycyclic aromatic hydrocarbons (PAHs) was studied in vivo and in vitro in systems consisting of Rigidoporus lignosus and its laccase, in the presence of so called "mediator" compounds. The static culture of the native fungal strain was able to metabolize anthracene and 2 methylanthracene, but not 9 nitroanthracene. The addition of redox mediators 2,2' azino bis (3 ethylbenzothiazoline 6 sulfonic acid) (ABTS) 1 hydroxybenzotriazole (HBT) or violuric acid (VA) led to a significant increase in the degradation of substrates. The oxidation of PAHs was not significant when purified laccase was used without the addition of mediators. The addition of these compounds increased the oxidation of all substrates by approximately 70 80% after 72 h of incubation. The degradation rate was highest for 2 methylanthracene in the presence of VA.
Applied biochemistry and biotechnology