Elucidation of biodegradation mechanism of Reactive Red 35 by Pseudomonas aeruginosa ARSKS20

The current work is aimed to evaluate the degradation of Reactive Red 35 (RR35) by Pseudomonas aeruginosa ARSKS20 that decolorized 100 mg/L dye at 8.27 mg/L/h rate under optimum conditions. Induction of laccase, lignin peroxidase, tyrosinase, Veratryl alcohol oxidase, NADH-DCIP reductase, azoreductase enzymes during dye decolorization suggested their active participation in dye degradation. Metabolites obtained after decolorization were analyzed with HPTLC and FTIR studies confirmed the biodegradation of dye. Metabolites produced after biodegradation of RR35 were identified by GC-MS analysis. Predicted pathway of biodegradation of RR35 by bacteria elucidated for first time. The results showed efficient biodegradation of RR35 to low molecular weight compounds, namely, 1-Amino-2-hydroxy-5-(2-sulfooxy ethyl) benzene , 1-amino2-methoxy benzene and naphthalene.