Preliminary studies on bacterial decolorization of H-acid based azo dye-reactive black 5.

A co-culture acclimatized to H-acid was used to degrade Reactive Black 5 (RB 5), a bis azo dye having central H-acid function. The effect of substrate concentration, pH and medium composition on the decolorization has been investigated. Decolorization was found independent of pH. Luria-Bertani broth favored decolorization over Yeast Extract; however further decolorization experiments have been conducted using Yeast Extract. The Michaelis-Menten Kinetic model is found to describe the dependence of specific decolorization rate on the RB 5 dye concentration.