Application of response surface methodology for the optimization of textile effluent biodecolorization and its toxicity perspectives using plant toxicity, plasmid nicking assays

Textile effluents are hugely hazardous, and comparatively less research have been focused on their biodecolorization process optimization by single bacterium. Hence, present study was intended toward statistical optimization of textile wastewater biodecolorization by Pseudomonas sp. SUK1 employing response surface methodology. Effects of pH, temperature, and effluent concentrations were analyzed, and an optimal response of 92.20 % American Dye Manufacturing Institute (ADMI) value removal was recorded at 7.0 pH, 40 °C, and 40 % of effluent concentration. This response was maximized to 94.08 % ADMI removal from predicted solutions. Actual and predicted values were matching and the process was found suitable for quadratic model. Success of response surface methodology was validated from R ². Significant interactions of each variable were demonstrated by response surface plots. Bacterium reduced the heavy metals concentration, Biological Oxygen Demand, and Chemical Oxygen Demand values significantly. Degradation of dyes was checked by high performance thin layer chromatography. Effluent treatment caused the nicking of pBR322. Up- /down- regulation of antioxidant enzymes in Allium cepa L. confirmed the severe toxicity of effluent and also suggested that the toxicity was significantly reduced by the bacterial treatment.