Immobilized Coprinus plicatilis biodegradation of fluorene in two different packed-bed reactors

Abstract

The biodegradation of fluorene by immobilized Coprinus plicatilis was studied in pinewood and foam glass bead-packed reactors. The reactors were operated in a sequencing batch system. Removal efficiency increased over time and elevated influent fluorene concentration (85 mg/L) was removed 100% in 24-30 h batch cycles. Increased laccase activity was detected with the introduction of the compounds, and optimum activity corresponded to optimum removal periods. Significantly higher laccase activity (16.7-19 U/L) was detected in the glass bead-packed reactor compared to the pinewood-packed reactor (0.2-5 U/L). The presence of Mn2+ ions in the wood material possibly caused elevated manganese peroxidase activity (0.3-5.8 U/L) compared to low to negligible activity in the glass bead reactor. Reactor performances are discussed in relation to sequencing batch operation and nutrient requirements necessary to induce and sustain fungal enzyme activity in inert-like organic material packed systems. Biodegradation metabolites were detected in samples via GC/MS.