Biodegradation of Two Textile Dyes by Bacillus Subtilis
Anas M. Almamoori, Duha Zeki Al-Swefee, Mays Mohammed Alzuhery
Abstract
This study revealed the efficiency of Bacillus subtilis in degrading two textile dyes (disperse red and  disperse yellow), the rates of red dye removal when measured after 24, 48, 72 and 96 hours for the concentrations  of 50 ppm were 51.67, 67.56, 84.67 and 95.33%, for the concentration 150 ppm were 41.67, 62.67, 80.67 and  89.67%, while for the concentration 300 ppm were 25.67, 42.67, 71.67 and 84.33%. The results of yellow dye  removal showed that the concentration of 50 ppm were 49.67, 65.33, 83.33 and 92.67%, for the concentration of  150 ppm were 38.33, 60.33, 77.33 and 87.33%, and for the concentration, 300 ppm were 24, 36.67, 68.33 and  81.67%, when measured after 24, 48, 72 and 96 hours. Results recorded a slight decrease in pH values for all  concentrations for each dye during 96 hours. Results also revealed a high reduction of EC and TDS values for  both dye concentrations after 96 hours.