Biodegradation of Pentachlorophenol in Soil Slurry Cultures by Bjerkandera adusta and Anthracophyllum discolor

Abstract

Pentachlorophenol (PCP) belongs to a class of environmental pollutants which have a high toxicity and are resistance to degradation. White-rot fungi are potential candidates for treating PCP-contaminated soils because of their high capability of degrading a wide range of xenobiotics. A series of laboratory-based studies was developed to determine the range of PCP concentration in soil (100, 250, and 350 mg of PCP/kg of soil) which could be degraded by two white-rot fungi: Bjerkandera adusta and Anthracophyllum discolor. Both fungi were grown on Kirk medium and on distillers dried grains with solubles (DDGS). The highest PCP degradation was attained by A. discolor using DDGS (95% after 28 days). The use of DDGS increased both PCP degradation and the production of ligninolytic enzymes, although no correlation was found between them. The process was scaled up to a 5 L reactor, in which 81% PCP was degraded after 28 days. The absence of ligninolytic activity of this culture indicates that other enzymatic systems may be participating in the degradation of PCP.