Selection of bacterial strains efficient in decolorization of remazol black-B

Azo dyes are released into wastewater streams without any pretreatment and polluted water and soil environments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of great importance. For this purpose, wastewater samples were collected from dye-contaminated sites of Ankleshwar, Gujarat, India. About 50 bacterial isolates were isolated through enrichment and then tested for their potential to remove Remazol Black-B azo dye in liquid medium. Three bacterial isolates capable of degrading Remazol Black-B azo dye efficiently were screened through experimentation on modified mineral salt medium. Isolate ETL-1 was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h. Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7) and at temperature 35 degrees C. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. The results imply that the isolate ETL-1 could be used for the removal of the reactive dyes from textile effluents.