The use of HRP in decolorization of reactive dyes and toxicological evaluation of their products

Abstract

This work studied the potential use of horseradish peroxidase (HRP) in the decolorization of the following textile dyes: Drimarene Blue X-3LR (DMBLR), Drimarene Blue X-BLN (DMBBLN), Drimarene Rubinol X-3LR (DMR), and Drimarene Blue CL-R (RBBR). Dyes were individually tested in the reaction media containing 120 mgL-1, considering the following parameters: temperature (20-45°C), H2O2 concentration (0-4.44 mmolL -1), and reaction time (5 minutes, 1 and 24 h). The following conditions: 35°C, 0.55 mmolL-1, and 1h, provided the best set of results of color removal for DMBLR (99%), DMBBLN (77%), DMR (94%), and RBBR (97%). It should be mentioned that only 5 minutes of reaction was enough to obtain 96% of decolorization for DMBLR and RBBR. After the decolorization reactions of DMBLR, DMR, and RBBR, it was possible to observe the reduction of Artemia salina mortality and the no significant increase in toxicity for the products generated from DMBBLN. © 2010 Michelle Reis da Silva et al.