Catalyzes the reductive cleavage of azo bond in aromatic azo compounds to the corresponding amines. Requires NADPH as an electron donor for its activity. Compounds with paired naphthalene groups coupled with the azo group are good substrates, with the following preference order: Rocceline > Sumifix Black B > Solar Orange. aniline + N,N-dimethyl-1,4-phenylenediamine + 2 NADP(+) = 4-(dimethylamino)azobenzene + 2 H(+) + 2 NADPH Optimum temperature is 70 degrees Celsius. Monomer. Constitutively expressed. Belongs to the azoreductase type 2 family.