A Sustainable Approach to Water Pollution Control: Microbial Decolorization and Detoxification of Basic Fuchsine-Contaminated Textile Effluent

Abstract

The discharge of dye-containing textile effluents poses a significant environmental challenge owing to their high color intensity, toxicity, and resistance to natural degradation. Among synthetic dyes, basic fuchsin is a recalcitrant triphenylmethane dye widely used in the textile industry and is known for its adverse effects on aquatic ecosystems and human health. In the present study, we isolated and evaluated potential bacterial strains capable of biodecolorizing textile wastewater amended with basic fuchsin dye. Textile effluents and contaminated soil samples were collected from a textile industrial site, and bacterial isolates were enriched and screened for decolorization efficiency. Eight bacterial isolates (TP1-TP8) were obtained, among which isolate TP7 exhibited the highest decolorization efficiency of 70.25 ± 1.0% under initial conditions. Morphological and microscopic characterization suggested that TP7 belonged to the genus Bacillus. Various physicochemical parameters affecting biodecolorization were optimized, including medium concentration, carbon source, nitrogen source, inoculum size, pH, and temperature. The optimum conditions were found to be 1× nutrient medium, 0.25% sucrose, 0.2% peptone, 3% inoculum size, pH 7, and 37°C, under which TP7 achieved a maximum decolorization efficiency of 99.99 ± 0.01% within 24 h. Enzymatic studies revealed significant manganese peroxidase (MnP) activity with a peak value of 7.9 U mL⁻¹ h⁻¹, indicating its involvement in dye degradation. Furthermore, phytotoxicity assessment using Vigna radiata demonstrated improved seed germination and growth in treated effluents compared to untreated wastewater, confirming substantial detoxification. The findings indicate that Bacillus sp. TP7 possesses remarkable potential for the efficient biodecolorization and detoxification of Basic Fuchsin-containing textile effluents, highlighting its suitability for sustainable bioremediation applications in industrial wastewater treatment.