Azo Dye Biodegradation Optimization by Cladosporium sp. Fungi: A Comprehensive Study on Decolorization Mechanisms, Process Parameters, and Environmental Applications

Abstract

Azo dyes constitute the biggest group of synthetic dyes utilized in textile industries and hence present a big problem to the environment because of their recalcitrant nature and possible toxicity. The work aims at studying the biodegradation capability of Cladosporium sp. in decolorization of azo dyes with regard to optimizing the process conditions as well as the possible degradation pathways. Cladosporium sp. exhibited significant decolorization ability on a wide range of azo dyes, and the optimization experiments indicated that the best decolorization activity was noticed under pH 6.5, temperature 30 C and under specific carbon and nitrogen source addition. There were two phenomena of biosorption and biodegradation revealed by the fungal strain and it was confirmed by spectroscopic analysis that the structure of the dye molecules was transformed. Methyl Red was decolorized with a maximum efficiency of 78 % based on the systematic optimization of physicochemical parameters. Kinetic The kinetic analysis indicated first-order degradation kinetics with rate constants between 0.0534 and 0.0847 day -1. The research proves the possibility of using Cladosporium sp. as a promising bioremediation agent in the textile wastewater treatment.