Biodegradation of Azo Dye Using the Isolated Novel Bacterial Species: Acinetobacter sp.

Abstract

Dyes present in water affect the balance of aquatic life as well as human being due to its toxicity. Insufficient sunlight impairs the process of photosynthesis of aquatic plants and phytoplankton, and, thus, they die without having sufficient food. After the death of these plants and animals, the numbers of zooplanktons and other higher organisms present in that aquatic system are automatically reduced. Finally, in this way the aquatic ecosystem loses its balance. The mixing of dye-colored wastewaters into the aquatic ecosystem and, thus, its accumulation in wildlife through food chain can cause many negative ecotoxicological effects and public health hazards.

Congo red dye is a type of azo dye which can cause harmful effects on environment. This present study aims to investigate the degradation of azo dye (Congo red) using bacterial species, Acinetobacter sp., at different variable parameters (pH, temperature, salinity, agitation, dye concentration, and inoculum volume). Optimum pH, temperature, salinity, agitation, dye concentration, and inoculum volume for this study are pH 7, 37 °C, 3 mg/L, 120 rpm., 50 mg/L, and 50 ml/L, respectively, to degrade the Congo red dye by using Acinetobacter sp. Optimum dye decolorization efficiency was found to be 87.89%.