Application of Extremophilic Microorganisms in Decolorization and Biodegradation of Textile Wastewater - Microbial Degradation of Synthetic Dyes in Wastewaters - page 263

2 Textile Dyes

Textile industry is a growing sector which, in turn, uses of textile dyes in a large
quantity (Dos Santos et al. 2007 ). Around 100,000 commercially available dyes can
be classi

ed according to their chromophoric groups, reactive groups, or even their
applications (Husain 2006 ; Dos Santos et al. 2007 ). Considering their chromophoric
groups, they fall into nine major classes as re ected in Table 1 (Rodr í guez Couto

2009 ).
Azo dyes constitute more than half of commercial dyes available in the market.
Any synthetic organic dyes, that contain nitrogen in azo group ( ) as part of

their molecular structures, fall into this class of dyes. Now-a-days more than 2000
different azoic dyes are being used in different industries and most of them are also

N=N

- -

Table 1 Chromophoric groups of textile dyes
Chromophoric group Structure

Acridine

Anthraquinone

Azo

Diazonium

Nitro

Oxazine

Phthalocyanine

Thiazine

Triarylmethane