Potential use of bacteria collected from human hands for textile dye decolorization

Abstract

We obtained dye-decolorizing bacteria from the hands of ordinary people with an efficiency of approximately 40%. The bacteria were classified into the azo dye-decolorizing group and anthraquinone dye-decolorizing group. The former were capable of decolorizing real textile wastewater, whereas the latter could achieve only partial decolorization. These bacterial strains can potentially be applied to assess the major types of dyes in textile wastewater and dye-polluted rivers. The azo dye-decolorizing bacterial strain degraded Congo red into its intermediates and then further degraded phenyl compounds. Interestingly, the azo dye-decolorizing bacterial strain produced a significant amount of protein (20–60 mg L−1), which correlated with the dye-decolorization rate. We further identified cell density as the main factor affecting stabilization of the dye-decolorization reaction. In summary, human hands are a readily accessible source from which to collect dye-decolorizing bacteria that can be used to treat textile wastewater and to remediate environmental pollution sites.