Evaluation of azo dyes degradation potential of Staphylococcus strains: A strategy for dye-waste management

Abstract

The current investigation aimed to identify the bacterial isolates that could prove helpful in the degeneration of harmful azo dyes from wastewater. The bacterial strains 1b, 1 m, and 4v could decolorize azo dyes up to 81 %, 79 %, and 87 % within 5 days. The degraded products by thin layer chromatography (TLC) showed Rf values of 0.89, 0.95, 0.90, 0.92, and 0.98 while the control showed an Rf value of 0.94. The comparison of the retention time of control and treated samples by the high-performance liquid chromatography (HPLC) system convinced that remarkable decolorization had occurred by the bacterial strains. The Fourier transform infrared spectroscopy (FTIR) analysis of the control and degraded samples was proof that the bond stretching occurred in the treated samples due to the action of bacterial strains. The release of compounds by bacteria i.e., 3-Aminobutanoic acid, pyrrolo pyrazine-1, 4-dione, and palmitic acid was inspected by Gas Chromatography-Mass Spectroscopy (GC-MS) analysis. No clear zones showed that the bacterial dye-degraded wastewater had no harm to the normal flora. At last, phytotoxicity was studied on Vigna radiata which had negative results. Given their pollutant degrading capabilities, these bacterial isolates are a good bioresource for green chemistry to exterminate azo dyes from the environment.