Bacterial Degradation of Azo Dye Congo Red by Bacillus sp.

Abstract In recent decades, azo dyes are more popularly used as synthetic dye for colorants compared to natural dye. The demand for dye colorants by industries is getting higher and this really gives negative effects on human health and ecology. Textile dyes are a major source of environmental pollution, aesthetic pollution, eutrophication, and problems in aquatic ecosystems. Biological treatment has come to be considered as cheaper than the physiochemical method and it is also environmentally eco-friendly. The broadly used synthetic azo dye is Congo red, as the target of textile effluent in wastewater. This study is to investigate the efficient degradation of bacteria against azo dyes by using biological treatment under aerobic condition by Bacillus sp bacteria. The highest percentage of efficiency of degradation at different condition was 83.12 % at 25 ppm with in 5 days at pH 7.55 and 30 °C, whereas the lowest percentage of efficiency of degradation at two different conditions is 9.00 % at 5 ppm within 1 day at pH 9.40 and 26 °C. As the conclusion, the effectiveness by degradation of Congo red dye Bacillus bacteria was within 5 days in 25 ppm. Thus by this present study, Bacillus could be used as a good microbial source for wastewater treatment, specifically in biological degradation of textile dye effluent in aerobic condition.