Microbial reduction of AZO dyes by several strains

Abstract

The microbial reduction of relatively simple azo dyes was investigated. The reduction in the initial step of the microbial degradation of the dyes was microorganism‐specific or dye‐specific, because the reduction of the dyes was directly dependent not only on the presence of azoreductase in the microorganisms, but on the permeation of the dye molecules into the cells. The cell permeability barrier of the dye molecules was observed for both sulfonated azo dyes and unsulfonated azo dyes. It was also observed that microbial azoreductase exhibit a narrow specificity.

Key words:

• azo dye
• microbial reduction
• microorganism‐specific
• dye‐specific
• cell‐permeability