Textile Dyes Degradation: A Microbial Approach for Biodegradation of Pollutants - Microbial Degradation of Synthetic Dyes in Wastewaters - page 183

Textile Dyes Degradation: A Microbial
Approach for Biodegradation of Pollutants

Lokendra Singh and Ved Pal Singh

1 Introduction

Rapid industrialization has given rise to various unwanted elements that accumulated
in the biosphere up to toxic levels to degrade the natural environment. Scienti c

developments are considered as key factors for progress of both developing and under
developed countries, but unfortunately, most of the industries in these countries do
not have proper waste treatment facilities and releasing a large quantity of ef

uents.
A majority of xenobiotics (either untreated or partially treated) released from
industries are mixed up with the natural water bodies and to the soil of the biosphere.
Untreated or partially treated textile ef

uents are highly toxic, as they contain a large
number of toxic chemicals and heavy metals. The problem of water pollution due to
the discharge of industrial wastewater into natural water bodies was witnessed by
western countries in 19th century and also in India after independence.
Until the discovery of synthetic alternatives, most of dyes were derived from
natural sources, such as plants and shell sh. These were only present in small

amounts and their extraction was often inef cient, so they were usually expensive.

In 19th century, there was a need to manufacture a large quantity of cheaper dyes
and pigments for textile industries. As a result synthetic dye industry became a
' industry of Victorian times, and its acknowledged founder was an

English chemist, William Henry Perkin. In 1856, Perkin, in his experiment with
aniline (one of the simplest chemical components of coal tar) obtained a black
precipitate and discovered purple color, which readily dyed silk and was much
more stable in sunlight than any other (natural) purple dye then in use. This

high-tech '

rst