A novel phenol-degrading filamentous fungus, strain JH6, was isolated from activated sludge and identified as a member of Paecilomyces variotii based on standard morphological and phylogenetic analysis. The degradation assays suggested that the strain was able to utilize phenol as the sole source of carbon and energy at concentrations up to 1800 mg/l. The strain exhibited optimum phenol degradation performance with the addition of 100 mg/l glucose at pH 5, 37 degrees C. Haldane's model could be fitted to the growth kinetics data well over a wide range of initial phenol concentrations (100-1800 mg/l), with kinetic values mu(max) = 0.312 h(-1), K-s = 130.4 mg/l, and K-i = 200 mg/l. The decay coefficient was found to be 0.0073 h(-1). Complete phenol degradation by strain JH6 could be achieved in the presence of other toxicants, such as m-cresol and quinoline, which were often found in the real phenol-containing wastewater. (C) 2010 Elsevier B.V. All rights reserved.