Detoxification and color removal of Congo red by a novel Dietzia sp. (DTS26)- A microcosm approach

Abstract

The present study deals with the decolorization and detoxification of Congo red (CR) by a novel marine bacterium Dietzia sp. (DTS26) isolated from Divar Island, Goa, India. The maximum decolorization of 94.5% (100mgL-1) was observed under static condition within 30h at pH 8 and temperature 32±2°C. Bacterially treated samples could enhance the light intensity by 38% and the primary production levels 5 times higher than the untreated. The strain was also able to reduce COD by 86.4% within 30h at 100mgL-1 of CR dye. The degraded metabolites of CR dye were analyzed by FTIR, HPLC, GC-MS and the end product closely matches with 4-amino-3-naphthol-1-sulfonate which is comparatively less toxic than CR. Bioassay experiments conducted in treated samples for Artemia franciscana showed better survival rates (after 72h) at higher concentration of CR (500mgL-1). This work suggests the potential application of DTS26 in bioremediation of dye wastes and its safe disposal into coastal environment.