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Aims: The dyes are high usage chemical compounds in textile industry. Discharge of colored effluent to the water sources, effect on the unpleasant appearance and the solubility of gases. The dyes reduce light penetration to the lower layers of water and photosynthetic activity. They caused cancers and variety of mutations. In this research, the decolorization ability of Reactive Red 152 dye by isolated strains from textile wastewater was measured, also environmental conditions were optimized.
Materials and Methods: In this experimental study, the bacterial strains were isolated from samples collected from different parts of textile wastewater. The dye decolorizing bacteria were screened. The decolorization ability of the strains was evaluated under different conditions such as incubation time from 0 to 72 hours, pH 6 to 9, different dye concentrations from 50 to 400mg/l and different carbon sources.
Findings: Ten strains were isolated from Kashan textile wastewater that 4 strains showed high ability in decolorization. The highest decolorization was observed after 48 hours, pH=9, 50mg/l concentration of dye and glucose as carbon source.
Conclusion: Textile wastewater contains bacterial strains which have high decolorization ability. Therefore, we can use these bacteria for decolorization of wastewater dyes.