Biodegradation and Decolourization of AZO Dyes Using Marine Bacteria

The azo aromatic is the most widespread dye class in the industry. They may have one or more azo (N=N) groups. The most commercially important are mono-azo dyes and di-azo dyes, tri-azo dyes, whereas poly azo are much less important. The disadvantage of these dyes are not easily decomposed by aerobic bacteria, but are degraded by anaerobic bacteria to aromatic amines like naphthylamines, chloro aniline. The dyes when they are exposed to the environment comprises a little percentage of water pollution, but in turn it is a indigenous environmental pollution and a public health concern. Two dyes such as Congo red and Erichrome Black T were used for the studies. Marine water sample was collected from Arabian Sea (Calicut) and Bay of Bengal (Ramanathapuram) and the laccase producing bacterial colonies were isolated. The marine bacterial laccases was characterized at different pH and temperature. Berge's Manual of Systemic Bacteriology has been used for describing the Bacteria. Then the isolates are observed for the decolourization of dyes under optimized conditions. The confirmation of dye decolourization was done through the spectral analysis at the wavelength range of 260 to760 nm at regular intervals of 5 nm.