Masood Arjmand

Plant Biochemistry of Xenobiotics. Mineralization of Chloroaniline/Lignin Metabolites from Wheat by the White-Rot Fungus, Phanerochaete chrysosporium

Abstract The lignin metabolites formed in wheat plants from [ring-u-14C]-4-chloroaniline and -3,4-dichloroaniline were isolated by a Björkman-type procedure and characterized by gel permeation chromatography and chemical degradation. The isolated metabolite fractions were then incubated with the white-rot fungus, Phanerochaete chrysosporium. Mineralization to [14C]carbon dioxide occurred in high yields, about 65% of the initial radioactivity of the lignin-bound chloroanilines being trapped as CO2 after an incubation period of 32-33 days. The lignin metabolites with the 14C-label in the aromatic ring of the chloroanilines were mineralized as readily as a non-xenobiotic control lignin with a 14C-label in the aromatic ring of coniferyl alcohol. It is concluded that the white-rot fungus studied has an unusually high capacity for the removal of chloroanilines and possibly other xenobiotic contaminants from the environment.

Mutagenicity of chloroaniline/lignin metabolites in the salmonella/microsome assay

Chloroanilines are constituents of many agrochemicals and have been found to be metabolized to succinic acid conjugates, e.g., succinamides and succinimides. The mutagenic potential of five chloroanilines and their succinamides and succinimide derivatives have been tested with two strains of Salmonella typhimurium (TA98 and TA100) with and without rat hepatic microsomal fraction. None of the compounds produced a dose response effect with a two-fold increase in revertants indicating that these compounds are not mutagens or promutagens in these assays.