Biodegradation and decolorization of triphenylmethane dyes by Staphylococcus epidermidis

Staphylococcus epidermidis isolated from textile wastewater were tested for their decolorization capacity. Biodegradation of Crystal violet, Phenol red, Malachite green, Methyl green and Fuchsin (750 ppm) were investigated within (12 h, 10 h, 14 h, 12 h and 10 h) under shaking condition in Mineral Salt Medium (MSM) solution at a pH of 7.5 and a temperature of 25 degrees C. Our results showed that Staphylococcus epidermidis had a high decolorization capacity. Using a 2.6 x 10(6) CFU/ml inoculum size. We noted also that decolorization of dyes solutions (750 ppm) was achieved after the addition of 0.10% (w/v) yeast extract and 7 mM of glucose in MSM. Chemical Oxygen Demand (COD) removal, FTIR and UV-Visible analysis confirmed biodegradation of dyes. The phytotoxicity and microbial toxicity studies of extracted metabolites suggested their least toxic nature. Our results suggest the potential use of Staphylococcus epidermidis in triphenylmethane dyes decolorization. Phytotoxicity studies revealed that biodegradation of dyes by a microbial culture, resulted in its detoxification. Thus treated effluent can be used for ferti-irrigation. (C) 2010 Elsevier B.V. All rights reserved.