Decolorization of Malachite Green by Live, Immobilized and Dead Biomass of Enterobacter asburiae XJUHX-4TM

Abstract

The dyes present in textile effluent impart persistent color to the receiving streams and interfere with photosynthesis of the phytoplankton and ecosystem. The triphenylmethane dye malachite green is highly soluble in water and has long been used in the aquaculture industry as a fungicide, parasiticide, and disinfectant. Malachite green is highly toxic to mammalian cells at concentrations as low as 0.1 mg/ml. It also enhances liver tumor formation in rats and causes reproductive abnormalities in rabbits and fish. A bacterial species namely Enterobacter asburiae XJUHX-4TM was isolated from dye contaminating site of a small scale dyeing industry, situated at Habra and was found to show high decolorizing activity against Malachite Green. Decolorization of Malachite was studied by the organism. The organism was utilized in its live form, immobilized form and heat killed-dry form. The organism was found to be most active with respect to decolorization in its live form. The live organism was found to be most promising decolorizer of the dye followed by its immobilized form and dry form. From the experiments conducted it was concluded that the organism is a potent decolorizer of the dye Malachite Green which can be utilized in the treatment of industrial effluent in subsequent studies.