Decolorization of triphenylmethane dyes and textile and dye-stuff effluentby Kurthia sp.

A number of soil and water samples were collected from the vicinity of effl uent treatment plant of a textile and dyeing industry. Several organisms we re screened for their ability to decolorize triphenylmethane group of dyes. A Kurthia sp. was selected on the basis of rapid dye decolorizing activity . Under aerobic conditions, 98% color was removed intracellularly by this s train. A number of triphenylmethane dyes, such as magenta, crystal violet, pararosaniline, brilliant green, malachite green, ethyl violet and textile and dyestuff effluent used in this study. The rates of decolorization of ma genta (92%) crystal violet (96%) malachite gr een (96%) pararosaniline (100 %) and brilliant green (100%) were found to be more than that of ethyl viol et (8%). After the decolorization of most of the dyes, viable cell concentr ation of the Kurthia sp. reduced significantly. In the case of ethyl violet , viable cell concentration was almost negligible after decolorization. The extent of decolorization of synthetic effluent (98%) was more in compariso n to textile and dye-stuff effluent (56%). After biotransformation, the ext ent of COD reduction of the cell free extracts of triphenylmethane dyes was higher (more than 88%, except in the case of ethyl violet, 70%) in compari son to textile and dye-stuff effluent. (C) 1999 Elsevier Science Inc. All r ights reserved.