Effects of culture parameters on the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenol (2,4-DCP) by selected fungi

In order to enhance 2,4-D and 2,4-DCP degradation by four selected fungi (C unninghamella elegans, C. echinulata, Rhizoctonia solani and Verticillium l ecanii), three culture parameters (initial chemical concentration, amounts of glucose and nitrogen) were varied. The levels of both xenobiotics in the culture media were monitored by HPLC analysis after five days of cultivati on. The best results were obtained at low initial concentration (20 mg.L-1 vs 100) and with low amounts of glucose (5 g.L-1 vs 10) and nitrogen (2.4 m M vs 24). When these two elements were lacking from the culture media, biod egradation was not suppressed, but took place to a lesser extent. Thus, ini tial chemical concentration and amounts of carbon and nitrogen, in the cult ure medium, were shown to strongly influence the extent of 2,4-D and 2,4-DC P removal by fungi.