Microbial decolorization of food industry azo dyes isolated from industrial wastewater

BACKGROUND AND OBJECTIVESAzo dyes used in textile, pharmaceutical, and food industries have emerged as a major environmental hazard due to their toxic and carcinogenic properties. Conventional wastewater treatment methods are often insufficient in effectively removing these recalcitrant compounds, leading to their discharge into water bodies, resulting in severe ecological and health issues. As a promising alternative, microbial degradation has gained significant attention as an eco-friendly approach for the efficient removal of azo dyes from contaminated sewage. Isolation and investigation of microorganisms which are able to remediate food industry azo dyes were the aims of the current study.MATERIALS AND METHODSTo isolate the microbial consortium able to decolorize azo dyes, samples were collected from the activated sludge in a food industrial wastewater treatment system. The edible azo dyes consisted of tartrazine, sunset yellow, and carmosin. The collected samples were inoculated into ۱۰۰ ml of R۲A medium containing ۵۰ mg L-۱ of individual dyes, and were then incubated at ۲۸ °C for ۷ days. Microbial decolorization was monitored using a spectrophotometer.RESULTS AND DISCUSSION Results demonstrated that the microbial consortium were able to decolorize the dyes for approximately ۶۰% after ۲۴ hours. The sunset yellow and carmosin dyes were decolorized more than ۹۰% after ۴۸ and ۷۲ hours, respectively. Furthermore, tartrazine was decolorized more than ۴۰% after ۷۲-۹۶ hours. These results revealed that the microbial consortium was able to decolorize food azo dyes and can be applied in industrial wastewater treatment plants.CONCLUSIONThese results revealed that the use of a microbial consortium with the capacity to decolorize azo dyes is an encouraging approach towards sustainable wastewater treatment system. This microbial consortium exhibits promising capabilities to decolorize azo dyes. These findings enhance our understanding of microbial decolorization processes and offer new prospects for addressing the growing concerns of azo dye pollution.

کلیدواژه ها:

Microbial decolorization ، food azo dyes ، industrial wastewater