Decoloring acid scarlet GR by a moderately halophilic bacterial consortium

Abstract:

[Objective] To obtain efficient decoloration bacterial consortium, which were able to degrade azo dyes in high salt environment and to biodegrade the dyeing wastewater. [Methods] A moderately halophilic bacterial consortium degrading of acid scarlet GR was enriched from activated sludge of dyeing wastewater. The community structure of the bacterial consortium was studied by high-throughput sequencing method, and the decoloring performance was studied under static condition. [Results] The moderately bacterial consortium was mainly composed by Halomonas, Salinicoccus, Nitratireductor and Aequorivita, Halomonas was the main decoloring bacteria. The degradation was inhibited by high concentration of NaCl, Na2SO4 and NaNO3, of which the strongest inhibition is NaNO3. The optimal decolorization conditions were as follows: pH 7.0, 30 °C, 5% NaCl. The moderately halophilic bacterial consortium could also degrade direct black 19 and disperse deep blue S-3BG. After continuous bleaching for 5 rounds, the degradation rate still reached over 98%. [Conclusion] The moderately halophilic bacteria consortium has strong potential to treat azo dye contaminated wastewater.