Decolourization and Degradation of Azo Dyes Blood Red and Turquoise Blue by Selected Soil Bacteria

Two soil bacterial isolates (Bacillus sp. and Staphylococcus sp.) were isolated from agricultural soil and used in the decolourization and degradation of two synthetic textile azo dyes blood red and turquoise blue. Of the two bacterial species employed, the isolate b (Staphylococcus sp.) caused better decolourization of blood red (72.40%) and turquoise blue (66.63%) than isolate a (Bacillus sp.). The bacterial consortium gave better decolourization (67.77%) for turquoise blue than with individual culture. Difference in the number of HPLC peaks between the intact dyes and the bacteria treated dyes confirms the bacterial biodegradation of azo dyes blood red and turquoise blue.