Biotransformation of Malachite Green by the Fungus Cunninghamella elegans

The filamentous fungus Cunninghamella elegans ATCC 36112 metabolized the triphenylmethane dye malachite green with a first-order rate constant of 0.029 μmol h(−1) (mg of cells)(−1). Malachite green was enzymatically reduced to leucomalachite green and also converted to N-demethylated and N-oxidized metabolites, including primary and secondary arylamines. Inhibition studies suggested that the cytochrome P450 system mediated both the reduction and the N-demethylation reactions.