Bioremediation of Azo Dye Brown 703 by Pseudomonas aeruginosa: An Effective Treatment Technique for Dye-Polluted Wastewater

Abstract

Dye-polluted wastewater poses a serious threat to humans’, animals’ and plants’ health, and to avoid these health risks in the future, the treatment of wastewater containing dyes is necessary before its release to environment. Herein, a biological approach is used; the textile azo dye brown 703 is degraded utilizing Pseudomonas aeruginosa. The bacterial strain was isolated from textile wastewater dumping sites in Mingora, Swat. The optimization for bacterial degradation was carried out on the nutrient broth medium, which was then subjected to a variety of environmental physicochemical conditions and nutritional source supplementation before being tested. Under micro-aerophilic circumstances, the maximum decolorization and degradation of dye occurred at a 20 ppm dye concentration within 3 days of incubation at a neutral pH and 38 °C. The decrease in the intensity of the absorbance peak in the UV–Vis spectrum was used to measure the extent of decolorization. Initially, 15 bacterial strains were isolated from the textile effluent. Out of these strains, Pseudomonas aeruginosa was found to be the most potent degrading bacteria, with a degradation extent of around 71.36% at optimum conditions. The appearance and disappearance of some new peaks in the FT-IR analysis after the degradation of brown 703 showed that the dye was degraded by Pseudomonas aeruginosa. The GC–MS analysis performed helped in identifying the degraded compounds of azo dye that were utilized in illustrating the under-study process of brown 703 degradation. The biodegradation brought about by Pseudomonas aeruginosa can be employed successfully in the future as an eco-friendly approach with far reaching results.

Exploring the decolorization efficiency and biodegradation mechanisms of different functional textile azo dyes by Streptomyces albidoflavus 3MGH

“…Reductive enzymes, such as azoreductase, are believed to cause azo bond deterioration, whereas oxidative enzymes, such as laccase, are believed to cause oxidative cleavage of the resulting amines to smaller intermediates [ 5 , 110 , 118 ]. The GC-MS analysis of the metabolite product profiles of the three dyes supported the proposed degradation mechanism by detecting significant numbers in the proposed fractionation [ 111 , 117 , 119 ].…”

“…It was proposed that the absence and shift of functional groups in dye-treated samples resulted in the development of new compound structures. The removal of noticeable peaks and the development of new peaks in the FTIR spectra of dye-decolorized metabolites demonstrate that S. albidoflavus 3MGH successfully biotransformed and mineralized dye samples into simple metabolites [ 111 , 116 , 117 ].…”