Azo dye degrading bacteria and their mechanism: A review

Abstract

Major part of the aesthetics and beauty of idols, textiles, paper, paintings industries, etc. finds its roots in the use of colours (azo compound). These synthetic dyes can not degrade easily by physical and chemical means and are toxic for the environment and animals including humans. Even if they get degraded, it becomes difficult to get rid of the secondary toxic products. Microbes especially bacteria can be used which results cheap, eco friendly and complete degradation of azo dye products without production of any secondary toxic products (or secondary products with way lesser toxicity). Also, it requires no new chemical to be added (in an attempt to degrade azo dye) in an already polluted environment, as the bacterial enzymes would do the job without requiring any other added chemicals. This review article discusses the use of bacteria for azo dye degradation, the bacterial enzymes such as laccase etc. that degrade azo dye and how they work to decolourise the dyes, the common genetic elements found in the different bacteria that can degrade azo dye. This article also includes information on future prospects and some genetically modified organism (GMO) that are being/ (can be) brought to use for dye degradation and pollution reduction.