ANAEROBIC DEGRADATION OF ACIFLUORFEN BY DIFFERENT ENRICHMENT CULTURES

A laboratory study on the biodegradation of acifluorfen in anaerobic conditions was conducted. Mixed and pure cultures isolated from activated sludges of a waste water treatment plant and from a soil with a long history of acifluorfen applications could reduce acifluorfen to aminoacifluorfen in a medium with the herbicide as sole source of carbon. Addition of sodium acetate and sodium 2-nitrobenzoate to the medium enhanced and decreased the reduction rate, respectively. A further transformation of aminoacifluorfen was observed with formation of 5-[[2-chloro-4-(trifluoromethyl)phenyl]oxy]-2-aminobenzamide and 5-[[2-chloro-4-(trifluoromethyl)phenyl]oxy]-2-(acetylamino)benzoic acid.