Determination of oxidized and reduced glutathione, by capillary zone electrophoresis, in Brassica juncea plants treated with copper and cadmium

Abstract

A rapid method of capillary zone electrophoresis is described to determine the oxidized (GSSG) and reduced (GSH) form of glutathione in plant tissue. In order to separate both analytes in a fused-silica capillary, the pH and composition of the electrolyte solution were optimized. The electrolyte composition was 100 mmol/L, borate 25 mmol/L Tris, and 0.2% w/v metaphosphoric acid (MPA), pH 8.2. Some instrumental conditions used to run the samples were hydrostatic injection for 30 s, 30 kV applied voltage, and UV detection (185 nm) at 25 degrees C. Linearity and useful range obtained for the calibration curves were optimum, with correlation coefficients about 0.999 in the 0-120 micromol/L range. The migration time was highly reproducible, less than 5 min being afforded to run a sample. Electrolyte buffer and samples required a careful pH control for optimal separation of both analytes. This aspect constitutes a critical analytical step when acids are used in the procedure for sample preparation. Simultaneous analysis of GSH and GSSG may provide a useful tool for comparative studies of plants in order to select those species with a potential capacity for detoxification from toxic elements or those appearing promising from phytoremediation for these elements.

Cadmium Stress Responses inBrassica juncea: Hints from Proteomics and Metabolomics

“…In the latter case, the poisonous metal is accumulated in the aerial part, a pivotal requirement for “phytoextractor” plants for phytoremediation purposes. , Among the Brassicaceae family, some species such as Brassica juncea were appreciated as potential heavy metal-phytoextractor candidates as they are suitable for bioremediation purposes. It is thus a small wonder that during the last 25 years, Indian mustard ( B. juncea ) has represented a key model to investigate the mechanisms underlying adaptation responses to Cd stress and accumulation. − …”

Characterization of the antioxidative activity of novel nontoxic neuropeptides by using capillary electrophoresis

“…Therefore, CE is a widely used method for the separation of proteins and peptides in various conditions such as acidic pH in the presence of a surfactant [18], in a nonaqueous environment [19], using a dynamic-or covalently bound capillary coating [20,21], and in miniaturization [22]. Recently, the qualitative and quantitative determination of GSSG and GSH was performed simultaneously using CE [23][24][25]. To date, only a few researchers have determined the oxidation rate constants by CE [26,27].…”

Simultaneous Determination of Glutathione and Glutathione Disulfide in an Acid Extract of Plant Shoot and Root by Capillary Electrophoresis

“…They were irradiated with artificial light at 400 µEinstein m -2 s -1 , with a 16-hour photoperiod, at day/night temperature of 24/20 °C and 50% relative humidity. The plants were grown in pots containing 1-L nutritive solution of definite composition and pH adjusted to 6.0 26 ; solution replacement for fresh solution was done every other day. Six repetitions, grown for 28 days, were utilized.…”

“…The extraction step thus generates an acidic matrix of an acid strength and pH which may affect the method sensitivity, cause comigration of species or changes in the equilibria relating both species in cells or fluids, possibly generating less representative results of the actual levels in living organisms. We have previously 26 proposed adjustment of the sample pH before CZE for better resolution of the signals of both peptides. However, the use of alkali for neutralization may imply the formation of a colloidal precipitate in the injection vial which may produce wrong signals or capillary obstruction if the colloid has not been previously visualized; additionally, it may increase analytical time in case precipitate separation is necessary.…”