Enhanced biodecolorization of azo dyes by co-immobilization of quinone-reducing consortium and anthraquinone

The decolorization rate of azo dyes under anaerobic conditions can be improved by the addition of water-soluble redox mediators.However,the continuous dosing and discharge of water-soluble redox mediators,such as biologically recalcitrant compounds,will result in the secondary contamination.The accelerating effect of co-immobilization of quinone-reducing consortium and insoluble anthraquinone in the biodecolorization of azo dyes was investigated for the first time.The cloning and sequencing analysis of ribosomal intergenic spacer (RIS) genes show that quinone-reducing community is predominate by Lactobacillaceae,Enterobacteriaceae!aod Bacteroidaceae;the decolorization rates of a broad range of azo dyes are greatly improved by co-immobilized beads as 1.3-2.1-fold increases;aftes ten repeated experiments,the decolorization rate of Active Red KE-3B by co-immobilized beads retains over 85%.