Decolorization of some reactive azo dyes by bacteria isolated from factories wastewater

The presence of azo dyes in the environment is an issue of major concern since they are highly recalcitrant and toxic. Azo dyes are extensively used in textile industries, and account for more than ۵۰% of the synthetic dyes used worldwide. Reactive azo dyes account for more than half of global dye production due to their ease of application, brilliant colors, and reactive units that quickly attach to fabrics. Releasing azo dyes into water bodies results in aesthetic problems and deteriorates water quality. This project described the degradation of three commercial model reactive dyes C.I.Reactive Yellow ۱۶۰ (RY۱۶۰), C.I.Reactive ۱۹۵ (RR۱۹۵) and C.I.Reactive ۱۲۲ (RO۱۲۲). For this purpose, wastewater samples were collected from three sites to isolate dye-decolorizing bacteria. The activity tests for microbial decolorization were performed in the culture medium containing ۵۰ mg L-۱ individual dyes using incubator shaker at ۳۰°C and ۱۲۰ rpm. About every ۷ days the culture was transferred to fresh medium. After ۳, ۵, and ۷ days the ratio of decolorization was recorded by measuring the absorbance of the sample. The results show a decrease in absorbance indicates color removal by bacteria.

کلیدواژه ها:

Bacterial Decolorization ، Azo Dye ، Reactive ، Wastewater