Desulfonation of the textile azo dye Acid Fast Yellow MR by newly isolated Aeromonas hydrophila SK16

Abstract Acid Fast Yellow MR (AFYMR), a sulphonated reactive textile azo dye, was effectively decolorized by a newly identified bacterial strain Aeromonas hydrophila SK16. Nineteen isolates were obtained from the textile effluent polluted soil in Perundurai region. Maximum decolorization of AFYMR was observed in Aeromonas hydrophila SK16. Enzyme activities present in A. hydrophila SK16 revealed the involvement of oxidoreductase and efficiently decolorized 91.25% of AFYMR (100 mg L-l) in static condition for 9 h. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that A. hydrophila SK16 cells preferred N–H and Sulphur dioxide bonds in the breakdown of AFYMR. The final metabolite supports the degradation of AFYMR through desulfonation as revealed by Gas Chromatography-Mass Spectroscopy (GCMS) results. Phytotoxicity studies conducted in Oryza sativa and Zea mays illustrated significant decrease in toxicity of metabolite produced during decolorization of Acid Fast Yellow MR by Aeromonas hydrophila SK16.