ABSTRACT
Azo dyes are widely used in the textile industry and are considered to be the largest class of commercial synthetic dyes. However, azo dyes are carcinogenic, mutagenic, and have low biodegradability. In addition, they potentially affect human health and the environment. For their removal from effluents, enzymatic degradation and biosorption have been highlighted as suitable methods. Oxidative enzymes, such as laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP) that are produced by fungi and other microorganisms can degrade azo dyes. However, the high costs associated with enzymes limit their environmental applications. Biosorption using residual materials is a simple and inexpensive method for the removal of azo dyes, without degradation. Simultaneous biosorption and enzymatic degradation might overcome these disadvantages, by using residual matter with naturally immobilized enzymes. The combination of these biological and physicochemical methods might improve the development of bioprocesses for the efficient removal and degradation of azo dyes in effluents.
