Investigation of biochemical response in rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) exposed to remazol brillant blue R textile dye

The dyes used in textile industry production are toxic substances and most of them have polymer structures. These dyes pollute the aquatic environment via various stages such as printing and dyeing, and may cause molecular, cellular, biochemical and physiological disorders. The aim of the present study was to evaluate effect of a highly toxic azo dye, Remazol Brillant Blue (RBBR) on the biochemical responses of rainbow trout, Oncorhynchus mykiss. The fishes were exposed to 0.5, 1 and 2 mg/l of RBBR for 24 and 48 h. The glutathione S-transferase (GST), cytochrome P-450 (CYP1A1) and lactate dehydrogenase (LDH) enzyme activities of these groups were measured. Present dye altered the activities of all these enzymes in the selected tissue of the experimental fish in a dose-dependent manner. According to the results of this study, after dye exposure, the alteration of selected enzymes indicated deterioration in antioxidant defense system, aerobic respiration processes and biotransformation mechanism induced by the tested dye. It was also shown that GST, CYP1A1 and LDH enzymes may be useful as biomarkers in determining the toxic effects in O. mykiss exposed to the RBBR textile dye.