Biological degradation of methane by an adapted consortium in steady state was compared in two reactor configurations (stirred tank, STR and trickling bed, TBR) with and without 10% (v/v) silicone oil. Silicone oil addition increased the methane average volumetric elimination capacity by 41% in STR up to 106 g m(-3) h(-1) and by 131% in TBR up to 51 g m(-3) h(-1). Specific elimination capacities showed higher degradation (69% in STR and 98% in TBR) Suggesting increased bioavailability. The elimination capacities obtained in both reactors with oil addition exceed most of experimental reports for methane biofiltration. (C) 2009 Elsevier B.V. All rights reserved.