Microbial cell factories in the degradation of azo-dye and their limiting factors: An insight

Azo dyes are the most commonly produced dyes worldwide, characterized by their distinct azo groups (-NN-) in their chemical structure. These dyes are xenobiotic and notably resistant to degradation. Approximately 20 % of all water body contamination is caused exclusively by textile effluents, which are released into the environment either deliberately or accidentally, leading to significant environmental toxicity. While numerous physical and chemical treatment methods are available, they each have their own drawbacks. Therefore, this comprehensive review explores the role of various microbes, including bacteria, bacterial consortia, fungi, algae, and lichens, along with their limiting factors. The review also delves into the role of various microbial enzymes and their encoding genes, as well as the molecular mechanisms involved. This study emphasizes the potential of microbial bioremediation as a cost-effective and eco-friendly tool for treating azo dye-contaminated water, in comparison to other techniques.