2008 journal article

Potential Applications of Oxidoreductases for the Re‐oxidation of Leuco Vat or Sulfur Dyes in Textile Dyeing

Engineering in Life Sciences, 8(3), 331–337.

By: F. Xu* & S. Salmon*

co-author countries: United States of America 🇺🇸
author keywords: biocatalysis; dyeing; oxidoreductases; peroxidase
Source: Crossref
Added: August 28, 2020

Abstract Conventional textile dyeing by vat and sulfur dyes includes reduction and re‐oxidation steps (with chemical reductants and oxidants), so that the insoluble dyes can be solubilized in the dyeing solution, adsorbed by the fabric, and fixed onto the dyed fabric. The treatments often involve hazardous chemicals, expensive catalysts, or conditions that are suboptimally effective, energy‐intensive, caustic, or polluting. Improving these steps with enzyme technology could be of significant interest in terms of better dyeing, handling of hazardous chemicals, disposal of waste, or production economy. The idea of an enzymatic re‐oxidation step for vat and sulfur dyeings was tested under simplified laboratory conditions. Selected vat and sulfur dyes, including Vat Blue 43, Vat Orange 7, Vat Green 3, Vat Orange 2, Vat Red 13, Vat Yellow 2, and Sulfur Black 1, were first chemically reduced. The reduced (leuco) dyes were then re‐oxidized by aerated buffer solutions or H 2 O 2 , in the presence or absence of an oxidoreductase, selected from seven laccases from Myceliophthora thermophila, Scytalidium thermophilum, Coprinus cinereus, Trametes villosa, Rhizoctonia solani, Pycnoporus cinnabarinus, Botrytis cinerea , a bilirubin oxidase from Myrothecium verrucaria, and a heme peroxidase from Coprinus cineresu . It was shown that the enzymes were able to catalyze and accelerate the re‐oxidation of the reduced dyes, even when they were adsorbed on cotton fabric, by dissolved air (O 2 ) or H 2 O 2 . Small redox‐active mediators could facilitate the enzymatic re‐oxidation. For Sulfur Black 1, a higher conversion of the leuco dye was achieved with laccase‐catalyzed re‐oxidation. The further development of this potential enzyme application is discussed.