The global textile industry, driven by the demand for cheap and fast fashion, is associated with massive water usage, carbon emissions, and labor and environmental compliance issues. Furthermore, the 100,000 or so industrial dyes and dye fixatives on the global market adversely affect downstream bodies of water and cause ecosystem damage due to their toxicity, carcinogenicity, and ability to block the penetration of light into aqueous systems. Current methods for removing dyes from effluent are primarily chemical (e.g., ozonation) and physical (e.g., membrane filtration) in nature, expensive and/or nonoptimal, and create large volumes of sludge, necessitating the discovery of cheaper, more benign methods to decolorize and degrade dyes.<br/><br/>The current research focuses on the novel use of heme proteins such as myoglobin, hemoglobin and SmFixL as enzyme catalysts in the oxidation of different groups of textile dyes using hydrogen peroxide. Because of their broad variety of binding sites, range of oxidation-reduction potentials, reactivity, and ubiquitous presence in biological species, heme proteins make desirable agents for bioremediation. The results show that the analyzed heme proteins bring about a rapid degradation of the anthraquinone dye Remazol Blue 19 (RB-19), the azo dye ponceau xylidine, and the textile dyes indigo carmine and malachite green within a pH range of 6.0 to 9.0. Kinetics data reveal that malachite green, indigo carmine, and RB-19 undergo faster degradation than the azo dyes studied. A comparative analysis of the catalytic effectiveness of different heme proteins on major dye classes will be presented, along with GC-MS studies of the degradation byproducts.

Turning heme proteins green: Novel applications of heme proteins in the bioremediation of azo, anthraquinone, indigoid, and triarylmethane industrial dye pollution

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.