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Ecofriendly methods involving bacteria and fungi are finding utilities for treatment of textile industry
effluents. A range of bacterial taxa have been introduced for decolorization of dyes most of which
are mesophilic. Those bacteria reported so far might have limitation with regards to their survival in
the nature as these have restrictions dealing with pH and temperature optima. As the textile effluent
discharged in the environment possesses varied physical and chemical properties; it is important to
extract those bacterial communities with properties that can withstand harsh environmental
conditions. Present study aims in extraction of bacteria with such properties. Bacteria able to
degrade DNA were carried further for their abilities to decolorize acid blue dye; one of the popular
dye in textile industry. These bacteria were fully characterized by 16S rRNA sequencing. These
halophilic bacteria have been extracted from Lonar Lake, Maharashtra, India. Of these two most
efficient bacteria namely Alishewanella sp and Bacillus on the basis of efficiency of decolorization of
acid blue dye were selected further. Both bacteria are able to grow over wide pH ranging from 5 to
13 and temperature ranging from 300C to 500C. Sufficient growth was also observed in nutrient
media containing salt concentration ranging from 0.5% to 2.5% with optimum growth at 2%. The
study suggests these bacteria would be suitable for decolorization of textile effluents possessing
different physiological properties. The study was further extended on periodic studies on dye
decolorization and it was found that 72h period was most suitbale for decolorization of acid bolue
dye. A period exceeding this could enhance marginal difference in dye decolorization. Despite such
growth optima the bacteria Alishewanella sp and Bacillus species could degrade 61.85% and
63.17% dye respectively. Accession number for Alishewanella sp and B. thuringiensis is JX298819
and JX298814 respectively.
Key words: Alishewanella, Bacillus, acid blue, dye, decolorization.