Improved Biodegradation of Reactive Red 120 by <i>Pseudomonas aeruginosa</i> JU_CHE_01: Isolation, Characterization, and Statistical Optimization

ABSTRACT A textile industry effluents contaminated soil‐derived strain of Reactive Red 120 (RR120) dye‐degrading bacteria was shown to be extremely effective and metabolically adaptable. Pseudomonas aeruginosa JU_CHE_01 (OR388872) was the isolated strain, as determined by phylogenetic analysis. P. aeruginosa JU_CHE_01 shown the ability to break down 600 mg/L concentration of RR120 dye along with many harmful textile azo dyes. The strain also showed resistance to ampicillin and cefradine but remained susceptible to other tested antibiotics. Five process factors were evaluated for optimal condition using the Taguchi approach. Three physicochemical parameters (pH, temperature, and inoculum dose) and two media components (glucose and yeast extract) were optimized because of their significant impact on RR120 biodegradation. The L‐18 orthogonal arrays (OAs) architecture was utilized in the design of multiple experimental studies. Analysis of the experimental data was done using the signal‐to‐noise (S/N) ratio with the “larger is better” features to determine the key variables and ideal circumstances for optimizing RR120 dye biodegradation. When the predicted data was validated using the confirmatory experiments, it was found that under the ideal conditions of glucose and yeast extract of concentration 1 g/L each, pH 8, temperature 37°C, and inoculum dose 10% (v/v) in 48 h, 97.63% of the RR120 dye degradation could be achieved, leading to a 66.75% enhancement in the RR120 degradation. Analysis of variance (ANOVA) indicated that the nitrogen source (yeast extract) and carbon source (glucose) significantly influenced RR120 biodegradation, accounting for 27.933% and 19.526%, respectively, followed by pH at 4.664%, temperature at 13.476%, and inoculum dose at 28.951%.