PADRONIZAÇÃO DA QUANTIFICAÇÃO DE GLUTATIONA REDUTASE EM Aegla singularis (ANOMURA, CRUSTACEA) UTILIZANDO PLANEJAMENTO EXPERIMENTAL DCCR

Abstract

STANDARDIZATION OF GLUTATHIONE REDUCTASE MEASURE IN Aegla singularis (ANOMURA, CRUSTACEA) USING DCCR EXPERIMENTAL PLANNING. Glutathione Reductase (GR) plays a key role in the maintenance of GSH homeostasis, variations in its activity may indicate damage from environmental contaminants. Experimental planning is a strategy to reduces time and cost in enzymatic assays. In this work, DCCR experimental planning was used to standardize and to validate the measure of GR in Aegla singularis bioindicator. Samples of A. singularis were collected in three watersheds with different percentages of naturalness and land uses. At all, were selected 7 streams, in which collections were performed at one upstream (most preserved) and one downstream (less preserved) point. Effects of temperature, reading time, substrate (GSSG) and protein concentration in GR reaction medium were evaluated, being that the two latter variables were optimized by DCCR. GR was not affected by temperature (15 to 30 °C) or reading time (6 and 10 minutes). Increased concentrations of proteins from biological extract had negative correlation with GR, whereas higher concentrations of GSSG resulted in higher GR activity. Environmental validation showed that GR in Aegla was influenced primarily by the watershed of origin. DCCR planning was efficient to optimizing the use of GR as a biomarker of environmental quality.